Control device, imaging device, control method, and program

Abstract

To provide a control device, an imaging device, a control method, and a program capable of maintaining constant brightness of a plurality of frames obtained by imaging with the imaging device even while an aperture is being driven.SOLUTION: A control device includes a processor that controls exposure of a plurality of frames obtained by capturing images using the imaging device, on the basis of the transmittance of an electronic neutral density filter mounted on the imaging device having a movable diaphragm and the driving time of the diaphragm.SELECTED DRAWING: Figure 20

Description

[Technical Field]

[0001] The present disclosure relates to a control device, an imaging device, a control method, and a program. [Background technology]

[0002] Patent Document 1 discloses an imaging device in which exposure conditions are set based on the characteristics of a transmittance control element. The imaging device described in Patent Document 1 includes a processor that calculates a first exposure condition range based on photometry of the imaging device, and if the first exposure condition range is not included in a second exposure condition range to which the control range acquired by the transmittance control element can be applied, changes the exposure conditions of the imaging device so that the calculated first exposure condition range is included in the second exposure condition range. Furthermore, the processor controls exposure using the transmittance control element in the second exposure condition range during imaging.

[0003] Patent Document 2 discloses an imaging device having an ND filter unit, a first exposure determination means, a second exposure determination means, and a control means. In the imaging device described in Patent Document 2, the ND filter unit has an ND filter with multiple densities, and the density of the ND filter inserted in the optical path is changeable. The first exposure determination means determines a first exposure control value including the density of the ND filter used for exposure control when imaging a subject. The second exposure determination means determines a second exposure control value including the density of the ND filter that is different from the first exposure control value. The control means controls the exposure when imaging a subject based on the second exposure determination means and the exposure control value determined by the first exposure determination means or the second exposure determination means. The first exposure control value has a greater number of changeable densities of the ND filter unit than the second exposure control value. The control means switches the first exposure control value to the second exposure control value at a predetermined timing.

[0004] In the imaging device described in Patent Document 3, the multiple exposure adjustment means include a first exposure adjustment means that adjusts the exposure amount by making an ND filter appear and disappear in the aperture opening, and a second exposure adjustment means consisting of at least one of an exposure adjustment means that adjusts the exposure amount by adjusting the opening area of ​​the aperture opening, an exposure adjustment means that adjusts the exposure amount by adjusting the electronic shutter speed of the solid-state imaging element, and an exposure adjustment means that controls the exposure amount by controlling the amplifier gain of the image signal obtained from the solid-state imaging element.

[0005] The exposure control method for an imaging device described in Patent Document 3 controls the first exposure adjustment means so that, when the brightness of the subject is below a predetermined level, the first exposure adjustment means is maintained in an ND filter fully open state in which the ND filter is not applied to the aperture at all, and, when the brightness of the subject is equal to or higher than the predetermined level, the first exposure adjustment means is maintained in an ND filter fully closed state in which the ND filter is applied to the entire aperture.Furthermore, the exposure control method for an imaging device described in Patent Document 3 controls the second exposure adjustment means so that, when the first exposure adjustment means causes a state transition between the ND filter fully open state and the ND filter fully closed state, the second exposure adjustment means generates an exposure change amount that offsets the exposure change amount accompanying the state transition of the first exposure adjustment means. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2021 / 193814 [Patent Document 2] Japanese Patent Application Publication No. 2018-198403 [Patent Document 3] Japanese Patent Application Laid-Open No. 2005-045648 Summary of the Invention

[0007] One embodiment of the present disclosure provides a control device, an imaging device, a control method, and a program that can maintain constant brightness for multiple frames obtained by capturing images using an imaging device, even while the aperture is being driven. [Means for solving the problem]

[0008] A first aspect of the present disclosure is a control device that includes a processor, and that controls the exposure of multiple frames obtained by capturing images using an imaging device having a movable aperture, based on the transmittance of an electronic neutral density filter mounted on the imaging device and the operating time of the aperture.

[0009] A second aspect of the present disclosure is a control device according to the first aspect, in which a processor controls the exposure of multiple frames by applying multiple split exposures to the exposure of the multiple frames, the split exposures being determined according to the relationship between the change time required for the transmittance to change from a first transmittance to a second transmittance that can achieve the target exposure of the imaging device and the aperture drive time.

[0010] A third aspect of the present disclosure is a control device according to the second aspect, in which a first control is performed when the change time and the drive time exceed a first threshold, and the first control is a control that keeps the change time within the drive time, and is a control that applies a plurality of first split exposures determined based on the actual change time, which is the time it takes to actually change from the first transmittance to the second transmittance, and the drive time, to the exposure of a plurality of frames as a plurality of split exposures.

[0011] A fourth aspect of the present disclosure is a control device according to the second or third aspect, in which a second control is performed when the change time and / or drive time is equal to or less than a first threshold, and the second control is a control that applies a plurality of second split exposures determined based on an ideal change time, which is the time it takes to ideally change from the first transmittance to the second transmittance, and the drive time, to the exposure of a plurality of frames as a plurality of split exposures.

[0012] A fifth aspect of the present disclosure is a control device according to the second aspect, in which a first control is performed when the difference between the change time and the drive time exceeds a second threshold, and the first control is a control that keeps the change time within the drive time, and is a control that applies a plurality of first split exposures determined based on the actual change time, which is the time it takes to actually change from the first transmittance to the second transmittance, and the drive time, to the exposure of a plurality of frames as a plurality of split exposures.

[0013] A sixth aspect of the present disclosure is a control device according to the second or fifth aspect, in which a second control is performed when the difference between the change time and the drive time is equal to or less than a second threshold, and the second control is a control that applies a plurality of second split exposures determined based on the ideal change time, which is the time it takes to ideally change from the first transmittance to the second transmittance, and the drive time, as a plurality of split exposures to the exposure of a plurality of frames.

[0014] A seventh aspect of the present disclosure is a control device according to any one of the third to sixth aspects, in which the multiple first divided exposures are determined based on a target exposure and a frame number determined based on a first frame number, which is the number of frames corresponding to the actual change time, and a second frame number, which is the number of frames corresponding to the drive time.

[0015] An eighth aspect of the present disclosure is a control device according to the seventh aspect, in which a plurality of first divided exposures are determined based on a plurality of first actual transmittances that define the process of realistically changing from the first transmittance to the second transmittance within the actual change time, an aperture value of the aperture, and a sensitivity and / or shutter speed that is set in the imaging device according to the target exposure.

[0016] A ninth aspect of the present disclosure is a control device according to the eighth aspect, in which, when the change time and the drive time exceed a third threshold, a third transmittance is determined between the first transmittance and the second transmittance so that the change time is within the drive time, and multiple first actual transmittances are determined based on the first transmittance and the third transmittance.

[0017] A tenth aspect of the present disclosure is a control device according to the eighth aspect, in which, when the difference between the change time and the drive time exceeds a fourth threshold, a third transmittance is determined between the first transmittance and the second transmittance so that the change time is within the drive time, and multiple first actual transmittances are determined based on the first transmittance and the third transmittance.

[0018] An eleventh aspect of the present disclosure is a control device according to the fourth or sixth aspect, in which the multiple second divided exposures are determined based on a target exposure and a number of frames determined based on a third number of frames, which is the number of frames corresponding to the ideal change time, and a fourth number of frames, which is the number of frames corresponding to the drive time.

[0019] A twelfth aspect of the present disclosure is a control device according to the eleventh aspect, in which the multiple second divided exposures are determined based on multiple ideal transmittances that define the process of ideally changing from the first transmittance to the second transmittance within an ideal change time, an aperture value of the aperture, and a sensitivity and / or shutter speed that is set in the imaging device according to the target exposure.

[0020] A thirteenth aspect of the present disclosure is a control device according to any one of the second to twelfth aspects, wherein, when the change time and drive time exceed a fifth threshold and a first difference, which is the difference between the fourth transmittance and the second transmittance that keeps the change time within the drive time, exceeds a predetermined difference, a divided exposure of the process of changing from the first transmittance to the second transmittance among the multiple divided exposures is determined based on multiple second actual transmittances that define the process of changing from the first transmittance to the second transmittance via multiple intermediate transmittances within the drive time, and the maximum difference, which is the maximum difference between the multiple intermediate transmittances and the second transmittance, is smaller than the first difference.

[0021] A fourteenth aspect of the present disclosure is a control device according to any one of the second to twelfth aspects, wherein, when the difference between the change time and the drive time exceeds a sixth threshold and the first difference, which is the difference between the fourth transmittance and the second transmittance that makes the change time within the drive time, exceeds a default difference, the divided exposure of the process of changing from the first transmittance to the second transmittance among the multiple divided exposures is determined based on multiple second actual transmittances that define the process of changing from the first transmittance to the second transmittance via multiple intermediate transmittances within the drive time, and the maximum difference, which is the maximum difference between the multiple intermediate transmittances and the second transmittance, is smaller than the first difference.

[0022] A fifteenth aspect of the present disclosure is a control device according to the thirteenth aspect, in which, when the change time and drive time exceed a seventh threshold, the first difference exceeds a predetermined difference, and the transmittance change time, which is the time required to change from the first transmittance to the fourth transmittance, is less than an eighth threshold, a divided exposure in the process of changing from the first transmittance to the second transmittance among the multiple divided exposures is determined based on the multiple second actual transmittances.

[0023] A sixteenth aspect of the present disclosure is a control device according to the fourteenth aspect, in which, when the difference between the change time and the drive time exceeds a ninth threshold, the first difference exceeds a predetermined difference, and the transmittance change time, which is the time required to change from the first transmittance to the fourth transmittance, is less than a tenth threshold, a split exposure in the process of changing from the first transmittance to the second transmittance among the multiple split exposures is determined based on the multiple second actual transmittances.

[0024] A 17th aspect of the present disclosure is a control device according to the 15th or 16th aspect, in which the multiple first divided exposures are determined based on a target exposure and a frame number determined based on a fifth frame number, which is the number of frames required to change from the first transmittance through multiple second actual transmittances to the second transmittance, and a sixth frame number, which is the number of frames corresponding to the drive time.

[0025] An 18th aspect of the present disclosure is a control device according to the 17th aspect, in which the multiple first divided exposures are determined based on multiple third actual transmittances that define the process by which the change time changes from the first transmittance through multiple intermediate transmittances to the second transmittance within the driving time, the aperture value of the aperture, and the sensitivity and / or shutter speed that are set in the imaging device according to the target exposure.

[0026] A 19th aspect of the present disclosure is a control device according to any one of the second to eighteenth aspects, in which, when the transmittance cannot follow changes in the aperture value of the aperture, the exposure of multiple frames is determined based on the first transmittance and the drive time.

[0027] A twentieth aspect of the present disclosure is a control device according to any one of the second to nineteenth aspects, in which, when the transmittance cannot follow changes in the aperture value of the aperture and the change in the aperture value is equal to or less than a first predetermined change amount, the exposure of multiple frames is determined based on the first transmittance and the drive time.

[0028] A 21st aspect of the present disclosure is a control device according to any one of the 2nd to 20th aspects, in which, if the change in aperture value due to an aperture value update exceeds a second predetermined change amount while the exposure of multiple frames is being controlled, the exposure of multiple frames is updated in a manner according to the responsiveness of the transmittance to the difference between the aperture value before the update and the aperture value after the update.

[0029] A 22nd aspect of the present disclosure is the control device according to any one of the 1st to 21st aspects, wherein the plurality of frames are obtained by capturing images based on a default frame rate.

[0030] A 23rd aspect of the present disclosure is an imaging device including the control device according to any one of the first to 22nd aspects and an image sensor used for imaging.

[0031] A 24th aspect of the present disclosure is a control method that includes controlling the exposure of multiple frames obtained by capturing images using an imaging device having a movable aperture, based on the transmittance of an electronic neutral density filter mounted on the imaging device and the operating time of the aperture.

[0032] A 25th aspect of the present disclosure is a program for causing a computer to execute a process including controlling the exposure of multiple frames obtained by capturing images using an imaging device having a movable aperture, based on the transmittance of an electronic neutral density filter mounted on the imaging device and the operating time of the aperture. [Brief explanation of the drawings]

[0033] [Figure 1] 1 is a schematic diagram illustrating an example of the overall configuration of an imaging device. [Figure 2] FIG. 1 is a schematic diagram illustrating an example of a hardware configuration of an optical system and an electrical system of an imaging apparatus. [Figure 3] FIG. 10 is a conceptual diagram showing an example of changes in transmittance and aperture value when the current aperture value is changed to the target aperture value before the target number of frames is reached and the brightness of multiple frames is kept constant. [Figure 4] FIG. 10 is a conceptual diagram showing an example of changes in transmittance and aperture value when the transmittance of the electronic ND filter is changed but the change in transmittance of the electronic ND filter is not completed in time to reach the target number of frames. [Figure 5] FIG. 2 is a block diagram showing an example of how the system controller operates. [Figure 6] FIG. 10 is a conceptual diagram showing an example of a part of the processing contents of exposure control processing performed by a processor when the aperture value is fixed. [Figure 7] FIG. 10 is a conceptual diagram showing an example of a part of the processing contents of exposure control processing performed by a processor when the aperture value is fixed. [Figure 8] FIG. 10 is a conceptual diagram showing an example of a part of the processing contents of exposure control processing performed by a processor when the aperture value is fixed. [Figure 9]FIG. 10 is a conceptual diagram showing an example of a part of the processing contents of exposure control processing performed by a processor when the aperture value is fixed. [Figure 10] FIG. 10 is a conceptual diagram showing an example of a part of the processing contents of exposure control processing performed by a processor when the aperture value is fixed. [Figure 11] 10 is a conceptual diagram showing an example of a part of the processing contents of the exposure control processing performed by the processor when the aperture value is changed and the change in the aperture value cannot be tracked by the electronic ND filter. FIG. [Figure 12] 10 is a conceptual diagram showing an example of a part of the processing contents of the exposure control processing performed by the processor when the aperture value is changed and the change in the aperture value cannot be tracked by the electronic ND filter. FIG. [Figure 13] 10 is a conceptual diagram showing an example of a part of the processing contents of the exposure control processing performed by the processor when the aperture value is changed and the change in the aperture value cannot be tracked by the electronic ND filter. FIG. [Figure 14] FIG. 10 is a conceptual diagram showing an example of a portion of the processing content of exposure control processing performed by a processor when the aperture value is changed and the change in aperture value can be tracked by an electronic ND filter. [Figure 15] FIG. 10 is a conceptual diagram showing an example of a condition under which the first control or the second control is performed when the aperture value is changed and the change in the aperture value can be followed by the electronic ND filter. [Figure 16] FIG. 4 is a conceptual diagram showing an example of the content of a first control. [Figure 17] FIG. 4 is a conceptual diagram showing an example of the content of a first control. [Figure 18] FIG. 4 is a conceptual diagram showing an example of the content of a first control. [Figure 19] FIG. 4 is a conceptual diagram showing an example of the content of a first control. [Figure 20] FIG. 4 is a conceptual diagram showing an example of the content of a first control. [Figure 21] FIG. 10 is a conceptual diagram showing an example of the content of second control. [Figure 22] FIG. 10 is a conceptual diagram showing an example of the content of second control. [Figure 23]FIG. 10 is a conceptual diagram showing an example of the content of second control. [Figure 24] FIG. 10 is a conceptual diagram showing an example of the content of second control. [Figure 25] FIG. 4 is a conceptual diagram showing an example of the content of a first control. [Figure 26A] 6 is a flowchart showing an example of the flow of exposure control processing according to the first embodiment. [Figure 26B] This is a continuation of the flowchart shown in FIG. 26A. [Figure 26C] This is a continuation of the flowchart shown in FIG. 26B. [Figure 26D] This is a continuation of the flowchart shown in FIG. 26A. [Figure 26E] This is a continuation of the flowchart shown in FIG. 26A. [Figure 26F] This is a continuation of the flowchart shown in FIG. 26E. [Figure 26G] This is a continuation of the flowchart shown in FIG. 26E. [Figure 27] 10 is a flowchart showing an example of the flow of exposure control processing according to the second embodiment. [Figure 28A] 11 is a flowchart showing an example of the flow of exposure control processing according to the third embodiment. [Figure 28B] This is a continuation of the flowchart shown in FIG. 28A. [Figure 28C] 11 is a flowchart showing an example of the flow of exposure control processing according to the third embodiment. [Figure 28D] This is a continuation of the flowchart shown in FIG. 28C. [Figure 28E] 11 is a flowchart showing an example of the flow of exposure control processing according to the third embodiment. [Figure 28F] This is a continuation of the flowchart shown in FIG. 28E. [Figure 29A] 13 is a flowchart showing an example of the flow of exposure control processing according to the fourth embodiment. [Figure 29B] This is a continuation of the flowchart shown in FIG. 29A. [Figure 29C] This is a continuation of the flowchart shown in FIG. 29A. [Figure 30] FIG. 10 is a conceptual diagram showing an example of how a plurality of predicted transmittances including a plurality of intermediate transmittances change. [Figure 31] 10 is a flowchart illustrating a modified example of the flow of exposure control processing according to each embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0034] Hereinafter, examples of embodiments of a control device, an imaging device, a control method, and a program according to the present disclosure will be described with reference to the accompanying drawings.

[0035] First, the terms used in the following description will be explained.

[0036] CPU is an abbreviation for "Central Processing Unit". GPU is an abbreviation for "Graphics Processing Unit". GPGPU is an abbreviation for "General-purpose computing on graphics processing units". APU is an abbreviation for "Accelerated Processing Unit". TPU is an abbreviation for "Tensor processing unit". NVM is an abbreviation for "Non-volatile memory". RAM is an abbreviation for "Random Access Memory". IC is an abbreviation for "Integrated Circuit". ASIC is an abbreviation for "Application Specific Integrated Circuit". PLD is an abbreviation for "Programmable Logic Device". FPGA is an abbreviation for "Field-Programmable Gate Array". SoC is an abbreviation for "System-on-a-chip". SSD is an abbreviation for "Solid State Drive". USB is an abbreviation for "Universal Serial Bus". EEPROM is an abbreviation for "Electrically Erasable and Programmable Read Only Memory". I / F is an abbreviation for "Interface". UI is an abbreviation for "User Interface". CMOS is an abbreviation for "Complementary Metal Oxide Semiconductor". CCD is an abbreviation for "Charge Coupled Device". fps is an abbreviation for "Frames per second". MF is an abbreviation for "Manual focus". AF is an abbreviation for "Auto focus". AE is an abbreviation for "Auto Exposure". ND is an abbreviation for "Neutral Density". EL is an abbreviation for "Electro Luminescence".

[0037] In the following description, a coded processor (hereinafter simply referred to as a "processor") may be a single physical or virtual computing device, or a combination of multiple physical or virtual computing devices. Furthermore, a processor may be a single type of computing device, or a combination of multiple types of computing devices. Examples of computing devices include a CPU, a GPU, a GPGPU, an APU, or a TPU.

[0038] In the following description, a signed memory is a memory such as a RAM in which information is temporarily stored, and is used as a work memory by a processor.

[0039] In the following description, the term "storage" refers to one or more nonvolatile storage devices that store various programs, various parameters, etc. Examples of nonvolatile storage devices include flash memory, magnetic disks, and magnetic tapes. Another example of storage is cloud storage.

[0040] In the following embodiments, the external I / F with a symbol controls the exchange of various information between multiple devices connected to each other. An example of the external I / F is a USB interface. A communication I / F including a communication processor, an antenna, etc. may be applied to the external I / F. The communication I / F controls communication between multiple computers. An example of a communication standard applied to the communication I / F is a wireless communication standard including 5G, Wi-Fi (registered trademark), Bluetooth (registered trademark), etc.

[0041] In the following embodiments, "A and / or B" is synonymous with "at least one of A and B." In other words, "A and / or B" means that it may be only A, only B, or a combination of A and B. In addition, in this specification, the same concept as "A and / or B" is also applied when three or more things are expressed by connecting them with "and / or."

[0042] [First embodiment] As shown in FIG. 1 as an example, an imaging device 10 is a device that captures an image of a subject, and includes a system controller 12, an imaging device body 16, and an interchangeable lens 18. The imaging device 10 is an example of an "imaging device" according to the present disclosure, and the system controller 12 is an example of a "control device" and a "computer" according to the present disclosure. The system controller 12 is built into the imaging device body 16 and controls the entire imaging device 10. The interchangeable lens 18 is interchangeably attached to the imaging device body 16. The interchangeable lens 18 is provided with a focus ring 18A. The focus ring 18A is operated by a user of the imaging device 10 (hereinafter simply referred to as "user") when the user manually adjusts the focus of the imaging device 10 on a subject.

[0043] 1 shows an interchangeable lens digital camera as an example of the imaging device 10, but this is merely an example and a fixed lens digital camera may also be used. The present disclosure is also applicable to smart devices, wearable terminals, cinema cameras, television broadcasting video cameras, surveillance video cameras, cell observation devices, ophthalmic observation devices, surgical microscopes, etc. Smart devices, wearable terminals, television broadcasting video cameras, surveillance video cameras, cell observation devices, ophthalmic observation devices, surgical microscopes, etc. are examples of the "imaging device" according to the present disclosure.

[0044] The imaging device body 16 is provided with an image sensor 20. The image sensor 20 is an example of an "image sensor" according to the present disclosure. The image sensor 20 is a CMOS image sensor. The image sensor 20 captures an image of a subject, which is the imaging target. When an interchangeable lens 18 is attached to the imaging device body 16, subject light, which is light representing the subject, passes through the interchangeable lens 18 and is focused on the image sensor 20, and image data representing the image of the subject is generated by the image sensor 20.

[0045] In the first embodiment, a CMOS image sensor is exemplified as the image sensor 20, but the present disclosure is not limited to this, and the present disclosure also applies when the image sensor 20 is another type of image sensor, such as a CCD image sensor.

[0046] A release button 22 and a dial 24 are provided on the top surface of the imaging device body 16. The dial 24 is operated when setting the operation mode of the imaging system and the operation mode of the playback system, and by operating the dial 24, the imaging device 10 is selectively set as an operation mode among the imaging mode, playback mode, and setting mode. The imaging mode is an operation mode that causes the imaging device 10 to capture an image. The image is captured by operating a mechanical shutter (not shown) and / or an electronic shutter (not shown). The playback mode is an operation mode that plays back images (e.g., still images and / or moving images) obtained by capturing an image for recording in the imaging mode. The setting mode is an operation mode that is set for the imaging device 10 when, for example, setting various setting values ​​used in image capture-related controls.

[0047] The release button 22 functions as an imaging preparation instruction section and an imaging instruction section, and is capable of detecting two stages of pressing operation: an imaging preparation instruction state and an imaging instruction state. The imaging preparation instruction state refers to a state in which the button is pressed from a standby position to an intermediate position (e.g., a half-pressed position), for example, and the imaging instruction state refers to a state in which the button is pressed beyond the intermediate position to a final pressed position (e.g., a fully pressed position). Depending on the configuration of the imaging device 10, the imaging preparation instruction state may be a state in which the user's finger is in contact with the release button 22, and the imaging instruction state may be a state in which the operating user's finger has moved from a state in which it is in contact with the release button 22 to a state in which it is released.

[0048] On the rear surface of the imaging device main body 16, instruction keys 26 and a touch panel display 32 are provided.

[0049] The touch panel display 32 includes a display 28 and a touch panel 30 (see also FIG. 2). An example of the display 28 is an EL display (e.g., an organic EL display or an inorganic EL display). The display 28 may be a different type of display, such as a liquid crystal display, instead of an EL display.

[0050] The display 28 displays images and / or text information, etc. When the imaging device 10 is in imaging mode, the display 28 is used to capture images for live view images, i.e., to display live view images obtained by continuous imaging. Here, a "live view image" refers to a moving image for display based on image data obtained by imaging by the image sensor 20. The imaging performed to obtain a live view image (hereinafter also referred to as "image capture for live view images") is performed based on a frame rate of, for example, 60 fps. 60 fps is merely an example, and a frame rate less than 60 fps (e.g., 30 fps) or greater than 60 fps (e.g., 180 fps) may also be used.

[0051] The display 28 is also used to display a still image obtained by capturing a still image when an instruction to capture a still image is given to the imaging device 10 via the release button 22. The display 28 is also used to display a playback image when the imaging device 10 is in playback mode. Furthermore, the display 28 is also used to display a menu screen on which various menus can be selected when the imaging device 10 is in setting mode, and a setting screen for setting various setting values ​​used in imaging-related controls.

[0052] The touch panel 30 is a transmissive touch panel that is overlaid on the surface of the display area of ​​the display 28. The touch panel 30 receives instructions from the user (for example, an instruction to prepare for imaging and / or an instruction to capture an image, etc.) by detecting contact with a pointer such as a finger or a stylus pen.

[0053] In the first embodiment, an out-cell type touch panel display in which the touch panel 30 is overlaid on the surface of the display area of ​​the display 28 is given as an example of the touch panel display 32, but this is merely an example. For example, an on-cell type or an in-cell type touch panel display can also be used as the touch panel display 32.

[0054] The instruction keys 26 accept various instructions. Here, "various instructions" refers to, for example, an instruction to display a menu screen, an instruction to select one or more menus, an instruction to confirm a selection, an instruction to erase a selection, an instruction to zoom in, zoom out, and frame-by-frame advance. These instructions may also be given via the touch panel 30.

[0055] As an example, as shown in FIG. 2, the image sensor 20 includes a photoelectric conversion element 72. The photoelectric conversion element 72 has a light-receiving surface 72A. The photoelectric conversion element 72 is disposed within the imaging device body 16 so that the center of the light-receiving surface 72A coincides with the optical axis OA (see also FIG. 1). The photoelectric conversion element 72 has a plurality of photosensitive pixels arranged in a matrix, and the light-receiving surface 72A is formed by the plurality of photosensitive pixels. Each photosensitive pixel has a microlens (not shown). Each photosensitive pixel is a physical pixel having a photodiode (not shown), which photoelectrically converts received light and outputs an electrical signal according to the amount of received light.

[0056] In addition, the multiple photosensitive pixels have red (R), green (G), or blue (B) color filters (not shown) arranged in a matrix in a predetermined pattern arrangement (e.g., Bayer arrangement, G-stripe R / G complete checkerboard, X-Trans (registered trademark) arrangement, honeycomb arrangement, etc.).

[0057] The interchangeable lens 18 includes an imaging lens 40. The imaging lens 40 has an objective lens 40A, a variable magnification lens 40B, and a movable diaphragm 40C. Here, the movable diaphragm 40C is an example of the "movable diaphragm" according to the present disclosure.

[0058] The objective lens 40A, the variable magnification lens 40B, and the aperture 40C are arranged in this order along the optical axis OA from the subject side (object side) to the imaging device body 16 side (image side).

[0059] The interchangeable lens 18 also includes a control device 36, a first actuator 37, and a second actuator 38. The control device 36 controls the entire interchangeable lens 18 in accordance with instructions from the imaging device body 16. The control device 36 is a device having a computer including, for example, a CPU, NVM, RAM, etc. The RAM of the control device 36 temporarily stores various types of information and is used as work memory. In the control device 36, the CPU reads necessary programs from the NVM and executes the various read programs on the RAM to control the entire imaging lens 40.

[0060] Although a device having a computer is given here as an example of the control device 36, this is merely an example, and devices including ASIC, FPGA, and / or PLD may also be applied. Furthermore, the control device 36 may be, for example, a device realized by a combination of hardware and software configurations.

[0061] The first actuator 37 includes a magnification change slide mechanism (not shown) and a magnification change motor (not shown). A magnification change lens 40B is attached to the magnification change slide mechanism so as to be slidable along the optical axis OA. A magnification change motor is also connected to the magnification change slide mechanism, and the magnification change slide mechanism operates by receiving power from the magnification change motor to move the magnification change lens 40B along the optical axis OA.

[0062] The second actuator 38 includes a power transmission mechanism (not shown) and an aperture motor (not shown). The aperture 40C has an opening 40C1, the size of which is variable. The opening 40C1 is formed, for example, by a plurality of aperture blades 40C2. The plurality of aperture blades 40C2 are connected to the power transmission mechanism. The power transmission mechanism is also connected to an aperture motor, which transmits the power of the aperture motor to the plurality of aperture blades 40C2. The plurality of aperture blades 40C2 operate in response to the power transmitted from the power transmission mechanism, thereby changing the size of the aperture 40C1. The aperture 40C adjusts the exposure by changing the size of the aperture 40C1.

[0063] The magnification motor and the aperture motor are connected to the control device 36, and the control device 36 controls the driving of each of the magnification motor and the aperture motor. In the first embodiment, a stepping motor is used as an example of the magnification motor and the aperture motor. Therefore, the magnification motor and the aperture motor operate in synchronization with pulse signals in response to commands from the control device 36. Also, while an example is shown here in which the magnification motor and the aperture motor are provided in the interchangeable lens 18, this is merely an example, and at least one of the magnification motor and the aperture motor may be provided in the imaging device body 16. The components and / or operation method of the interchangeable lens 18 can be changed as necessary.

[0064] In the imaging mode, the imaging device 10 selectively sets MF mode and AF mode in accordance with instructions given to the imaging device body 16. MF mode is an operating mode in which the focus is adjusted manually. In MF mode, for example, when the user operates the focus ring 18A or the like, the variable magnification lens 40B moves along the optical axis OA by an amount corresponding to the amount of operation of the focus ring 18A or the like, thereby adjusting the focus.

[0065] In AF mode, the imaging device body 16 calculates the in-focus position according to the subject distance, and adjusts the focus by moving the variable magnification lens 40B toward the calculated in-focus position. Here, the in-focus position refers to the position on the optical axis OA of the variable magnification lens 40B when the subject is in focus.

[0066] In the imaging mode, the imaging device 10 selectively sets either the manual exposure mode or the AE mode in accordance with instructions given to the imaging device body 16. The manual exposure mode is an operating mode in which exposure is adjusted manually, while the AE mode is an operating mode in which exposure is set automatically.

[0067] The imaging device main body 16 includes an image sensor 20, a system controller 12, an image memory 46, a UI device 48, an external I / F 50, a photoelectric conversion element driver 54, an ND filter driver 55, a motor driver 56, and an input / output interface 70. The image sensor 20 also includes a photoelectric conversion element 72 and an A / D converter 74.

[0068] The input / output interface 70 is connected to the system controller 12, image memory 46, UI device 48, external I / F 50, photoelectric conversion element driver 54, ND filter driver 55, motor driver 56, and A / D converter 74. The input / output interface 70 is also connected to the control device 36 of the interchangeable lens 18.

[0069] The system controller 12 includes a processor 64, storage 66, and memory 68. Here, the processor 64 is an example of a "processor" according to the present disclosure.

[0070] The processor 64, storage 66, and memory 68 are connected via a bus 75, which is connected to an input / output interface 70. Although the example shown in Fig. 2 shows a single bus as the bus 75 for convenience of illustration, multiple buses may be used. The bus 75 may be a serial bus or a parallel bus including a data bus, an address bus, a control bus, etc.

[0071] The storage 66 is a computer-readable non-transitory storage medium that stores various parameters and various programs. The various programs include an exposure control processing program PG (see FIG. 5), which will be described later. An example of the storage 66 is an EEPROM. The memory 68 temporarily stores various information and is used as a work memory. An example of the memory 68 is a RAM.

[0072] The processor 64 reads out a necessary program from the storage 66 and executes the read program in the memory 68. The processor 64 controls the entire imaging device 10 in accordance with the program executed on the memory 68. That is, in the example shown in Fig. 2, the image memory 46, the UI device 48, the external I / F 50, the photoelectric conversion element driver 54, the ND filter driver 55, the motor driver 56, the control device 36, etc. are controlled by the system controller 12.

[0073] The photoelectric conversion element 72 is connected to a photoelectric conversion element driver 54. The photoelectric conversion element driver 54 supplies an imaging timing signal that defines the timing of imaging performed by the photoelectric conversion element 72 to the photoelectric conversion element 72 in accordance with instructions from the processor 64. The photoelectric conversion element 72 performs resetting, exposure, and output of an electrical signal in accordance with the imaging timing signal supplied from the photoelectric conversion element driver 54. Examples of imaging timing signals include a vertical synchronization signal and a horizontal synchronization signal.

[0074] When the interchangeable lens 18 is attached to the imaging device body 16, subject light incident on the imaging lens 40 is imaged on the light-receiving surface 72A by the imaging lens 40. Under the control of the photoelectric conversion element driver 54, the photoelectric conversion element 72 photoelectrically converts the subject light received by the light-receiving surface 72A and outputs an electrical signal corresponding to the amount of subject light to the A / D converter 74 as analog image data indicating the subject light. Specifically, the A / D converter 74 reads out the analog image data from the photoelectric conversion element 72 in units of one frame and for each horizontal line using an exposure sequential readout method.

[0075] The A / D converter 74 digitizes the analog image data to generate a RAW image 79. The RAW image 79 is an image in which R pixels, G pixels, and B pixels are arranged in a mosaic pattern.

[0076] The processor 64 acquires the RAW image 79 from the A / D converter 74 and performs image processing on the acquired RAW image 79 .

[0077] The image memory 46 stores a frame 80. The frame 80 is an image obtained by the processor 64 performing image processing on the RAW image 79.

[0078] The UI device 48 includes a display 28, and the processor 64 displays various types of information on the display 28. The UI device 48 also includes a reception device 76. The reception device 76 includes a touch panel 30 and a hard key unit 78. The hard key unit 78 is a plurality of hard keys including the instruction keys 26 (see FIG. 1). The processor 64 operates in accordance with various instructions received by the touch panel 30.

[0079] The external I / F 50 controls the exchange of various information with devices external to the imaging device 10 (hereinafter also referred to as "external devices"). External devices (not shown), such as a smart device, a personal computer, a server, a USB memory, a memory card, and / or a printer, are directly or indirectly connected to the external I / F 50. The external I / F 50 is also connected to a network (not shown). The external I / F 50 controls the exchange of information between the system controller 12 and a communication device (not shown), such as a server on the network. For example, the external I / F 50 transmits information in response to a request from the system controller 12 to the communication device via the network. The external I / F 50 also receives information transmitted from the communication device and outputs the received information to the system controller 12 via the input / output interface 70.

[0080] The imaging device 10 includes an electronic ND filter 58 and a clear glass 60. Here, the electronic ND filter 58 is an example of an "electronic neutral density filter" according to the present disclosure. The electronic ND filter 58 and the clear glass 60 are mounted on the imaging device body 16. The electronic ND filter 58 and the clear glass 60 are disposed on the subject side of the light receiving surface 72A. The electronic ND filter 58 and the clear glass 60 are disposed in this order from the subject side to the image side. Note that, while an example in which the electronic ND filter 58 and the clear glass 60 are mounted on the imaging device body 16 has been given here, this is merely an example, and at least the electronic ND filter 58 of the electronic ND filter 58 and the clear glass 60 may be mounted on the interchangeable lens 18.

[0081] The electronic ND filter 58 is an electronic variable neutral density filter made of a material containing liquid crystal molecules whose orientation changes when a voltage is applied. The electronic ND filter 58 adjusts the amount of light passing through the electronic ND filter 58 by changing its transmittance depending on the applied voltage. The transmittance of the electronic ND filter 58 can be changed seamlessly. Therefore, for example, when the aperture value is maintained, the transmittance of the electronic ND filter 58 is changed to achieve a target exposure (e.g., appropriate exposure for the brightness of the subject captured by the image capture device 10) while maintaining the depth of field. Furthermore, when the aperture value is changed, the transmittance of the electronic ND filter 58 is changed to compensate for the increase or decrease in exposure that accompanies the change in aperture value, making it possible to maintain a constant exposure even while the aperture value is changing.

[0082] An ND filter driver 55 is connected to the electronic ND filter 58. The ND filter driver 55 controls the transmittance of the electronic ND filter 58 by applying a voltage to the electronic ND filter 58 in accordance with instructions from the system controller 12.

[0083] The clear glass 60 is a glass plate having light-transmitting properties. An example of a glass plate having light-transmitting properties is a transparent glass plate. The optical path length of the clear glass 60 is the same as the optical path length of the electronic ND filter 58.

[0084] The imaging device 10 includes a shift mechanism 62. The shift mechanism 62 is mounted on the imaging device body 16. The shift mechanism 62 has a motor 62A. An example of the motor 62A is a stepping motor. The shift mechanism 62 transmits power generated by the motor 62A to the electronic ND filter 58 and the clear glass 60, thereby shifting the electronic ND filter 58 and the clear glass 60 in a direction transverse to the optical axis OA.

[0085] A motor driver 56 is connected to the motor 62A, and the motor 62A operates under the control of the motor driver 56 in accordance with instructions from the system controller 12. The motor 62A is mechanically connected to the electronic ND filter 58 and the clear glass 60 via a plurality of gears. The motor 62A applies power to the electronic ND filter 58 and the clear glass 60 under the control of the motor driver 56 in accordance with instructions from the system controller 12, thereby selectively inserting the electronic ND filter 58 and the clear glass 60 into or removing them from the optical path.

[0086] A plurality of gears mechanically connecting the motor 62A to the electronic ND filter 58 and the clear glass 60 imparts power in the rotational direction of the motor 62A to the electronic ND filter 58, and power in the opposite direction to the rotational direction of the motor 62A to the clear glass 60. For example, when forward rotation power is generated by the motor 62A, forward rotation power is imparted to the electronic ND filter 58, and reverse rotation power is imparted to the clear glass 60. When reverse rotation power is generated by the motor 62A, forward rotation power is imparted to the clear glass 60, and reverse rotation power is imparted to the electronic ND filter 58. In this way, by applying power from the motor 62A to the electronic ND filter 58 and the clear glass 60, one of the electronic ND filter 58 and the clear glass 60 is inserted into the optical path, and the other is removed from the optical path. Since the optical path length of the electronic ND filter 58 and the optical path length of the clear glass 60 are the same, even if the electronic ND filter 58 is removed from the optical path, the clear glass 60 is inserted into the optical path, so the same optical path length as when the electronic ND filter 58 is inserted into the optical path is maintained.

[0087] As an example, as shown in FIG. 3, when multiple frames 80 are obtained by capturing live view images, the aperture value of the aperture 40C (hereinafter simply referred to as the "aperture value") is the current aperture value FV current to the target aperture value FV target, the brightness of the frame 80 changes as the aperture value FV changes. In this case, from the current frame 80, the aperture value FV is changed to the current aperture value FV current to target aperture FV target It is preferable that the brightness be kept constant during the process of changing to frame 80 after the target number of frames A, which is the number of frames required for the change to the current aperture value FV current to target aperture FV target Target exposure EX target is preferably maintained.

[0088] One method for achieving this is to compensate for the change in brightness that accompanies the change in aperture value FV by changing the transmittance TR of the electronic ND filter 58 in accordance with the change in aperture value FV while maintaining the shutter speed (for example, the shutter speed of the mechanical shutter when a mechanical shutter is used, or the shutter speed of the electronic shutter when an electronic shutter is used) and the sensitivity of the photoelectric conversion element 72 (for example, ISO sensitivity) during the process of changing from the current frame 80 to the frame 80 that is the target number of frames A later.

[0089] In the example shown in FIG. 3, the transmittance TR of the electronic ND filter 58 is changed in accordance with the change in the aperture value FV, and is set to the current transmittance TR , which is the transmittance TR of the electronic ND filter 58 at the timing when the image capture device 10 starts the exposure calculation. current Target exposure EX to maintain the brightness of frame 80 at the target brightness target Achievable target transmittance TR target It has been changed to.

[0090] Since the aperture value changes monotonically (linearly in the example shown in FIG. 3), the transmittance TR of the electronic ND filter 58 is changed to the current transmittance TR in accordance with the change in the aperture value FV. current to target transmittance TR target If the brightness is changed monotonically to , the brightness between frames 80 will be kept constant. However, to achieve this, the target frame number A and the change time T (i.e., the current transmittance TRcurrent to target transmittance TR target When the required number of frames B (=(frame rate FR used in capturing live view images) × (change time T)), which is the number of frames required during the elapse of the target frame number A, matches the required number of frames B, and frame 80 of the target frame number A is obtained, the transmittance TR of the electronic ND filter 58 is changed to the target transmittance TR target It is required to reach this goal.

[0091] However, as shown in Figure 4, the current transmittance TR current and target transmittance TR target Depending on the relationship between the number of required frames B and the target number of frames A, the required number of frames B may exceed the target number of frames A. In this case, the transmittance TR of the electronic ND filter 58 may not reach the target transmittance TR by the time the frame 80 of the target number of frames A is obtained. target In this way, if the time required to change the aperture value FV and the change time T do not match, the target exposure EX will not be reached within the target number of frames A. target In the example shown in FIG. 4, the transmittance TR of the electronic ND filter 58 is set to the target transmittance TR target is delayed by two frames from the target frame number A.

[0092] Therefore, in the first embodiment, the transmittance TR of the electronic ND filter 58 is made to follow the change in the aperture value FV within the target number of frames A, and in order to keep the brightness of the frame 80 constant (in other words, the target exposure EX target 5, an exposure control process is performed by the processor 64. An exposure control process program PG is stored in the storage 66. The exposure control process program PG is an example of a "program" according to the present disclosure. The processor 64 reads the exposure control process program PG from the storage 66 and executes the read exposure control process program PG in the memory 68. The exposure control process is realized by the processor 64 executing the exposure control process program PG. An example of the exposure control process will be described below.

[0093] 6 to 25 show an example of the contents of the exposure control process performed by the processor 64. First, as shown in Fig. 6 as an example, when the timing to start exposure calculation arrives, the processor 64 calculates a photometric value 90 indicating the brightness of the subject based on a frame 80 obtained by capturing an image for a live view image. Note that the photometric value 90 may be measured by an exposure meter (not shown).

[0094] Based on the photometric value 90, the processor 64 calculates a target exposure EX as an exposure for adjusting the brightness of the frame 80 used to calculate the photometric value 90 to a target brightness. target The processor 64 also calculates the target exposure EX target Target transmittance TR corresponding to target , i.e., target exposure EX target Achievable target transmittance TR target For example, the target transmittance TR target are the shutter speed SP, aperture value FV, sensitivity SE, and target exposure EX currently set for the image capture device 10. target The target transmittance TR is calculated based on the target The calculation of is performed using a target transmittance calculation formula 91. The target transmittance calculation formula 91 is a function of the shutter speed SP, the aperture value FV, the sensitivity SE, and the target exposure EX. target is the independent variable, and the target transmittance TR target is an arithmetic expression with as the dependent variable.

[0095] The processor 64 issues an instruction to change the aperture value FV to a different aperture value FV from the current aperture value FV, i.e., to change the aperture value FV to the current aperture value FV. current to target aperture FV target It is determined whether an aperture value change instruction (hereinafter simply referred to as an "aperture value change instruction") has been given to the imaging device 10. If an aperture value change instruction has not been given to the imaging device 10, the current aperture value FV, i.e., the current aperture value FV current The current aperture value FV currentWhen this condition is maintained, the processor 64 performs control to monotonically change the exposure applied to a plurality of frames 80, as shown in FIGS. 6 to 10 as an example.

[0096] As an example, as shown in Figure 6, the current aperture value FV current is maintained, the processor 64 sets the transmittance TR currently set for the electronic ND filter 58, i.e., the current transmittance TR current Then, the processor 64 obtains the obtained current transmittance TR current The calculated target transmittance TR target The change time T1, which is the time it takes for the transmittance to ideally change to TR, is calculated using a change time calculation formula 92. current to target transmittance TR target The ideal time to change to the current transmittance TR current to target transmittance TR target The change time calculation formula 92 is a time for which the target transmittance TR changes monotonically. A monotonous change refers to a change at a constant rate (for example, a linear change or an exponential change). target and current transmittance TR current In the first embodiment, the target exposure EX target is an example of a "target exposure" according to the present disclosure, and the current transmittance TR current is an example of the “first transmittance” according to the present disclosure, and the target transmittance TR target is an example of the "second transmittance" according to the present disclosure.

[0097] 7, the processor 64 determines whether the change time T1 exceeds a threshold value TH1. In the first embodiment, the threshold value TH1 is set to a value that is greater than the transmittance TR of the electronic ND filter 58 than the current transmittance TR current to target transmittance TR target The ideal waiting time until the target exposure EX changes to the aperture value FV, shutter speed SP, and sensitivity SE are fixed. targetThe threshold value TH1 may be a fixed value or a variable value that is changed according to given instructions or various conditions. An example of the threshold value TH1 is a value determined based on the transmittance TR of the electronic ND filter 58 being the current transmittance TR current to target transmittance TR target An example of the threshold value TH1 is the upper limit of the ideal waiting time until the transmittance TR of the electronic ND filter 58 changes to . Furthermore, the threshold value TH1 may be a time determined by the user, a time determined according to the type of imaging mode, or a time specified within a range of several percent to several tens of percent of the maximum time obtained from a table that defines the time it takes for the transmittance TR of the electronic ND filter 58 to change (for example, a time equivalent to 50% of the maximum time obtained from a table that defines the time it takes for the transmittance TR of the electronic ND filter 58 to change).

[0098] If the change time T1 does not exceed the threshold value TH1 (in other words, if the magnitude relationship of "change time T1≦threshold value TH1" holds), that is, if the transmittance TR of the electronic ND filter 58 is equal to or less than the current transmittance TR current Target Exposure EX target If the time required for the image to change to the current image falls within an ideal time, processor 64 calculates a required number of frames B1, which is the number of frames required during the change time T1, based on the change time T1 and the frame rate FR (for example, a frame rate equivalent to the frame rate described above). For example, the required number of frames B1 is calculated by "(change time T1) x (frame rate FR)".

[0099] The processor 64 determines the target exposure EX target and the change time T1, a plurality of split exposures EX div1 Get multiple split exposures EX div1 Get the target exposure EX target and the number of frames required B1, multiple split exposures EX div1 This is achieved by calculating the multiple split exposures EX div1 The calculation of is performed using the divided exposure calculation formula 93. The divided exposure calculation formula 93 calculates the current transmittance TR currentand Target Exposure EX target and the number of frames required B1 are used as independent variables, and multiple split exposure EX div1 is a calculation formula with the dependent variable as follows: div1 is the number of split exposures EX equivalent to the number of frames required B1. div1 is.

[0100] Multiple Split Exposure EX div1 is the current transmittance TR current Split Exposure EX div1 Target Exposure EX target For example, multiple split exposure EX div1 is the current transmittance TR current Split Exposure EX div1 Target Exposure EX target Although a linear change is illustrated here, it may also be an exponential change, as long as it changes monotonically in accordance with the change in aperture value FV.

[0101] Multiple Split Exposure EX div1 is the current transmittance TR current to target transmittance TR target (For example, the transmittance TR of the electronic ND filter 58 changes to the current transmittance TR current to target transmittance TR target The current transmittance TR is determined by the process of changing the transmittance at a constant rate. current , multiple ideal transmittances TR ideal1 , and target transmittance TR target In the example shown in FIG. 7, the current transmittance TR current The ideal transmittance TR corresponds to "1", "2", "3", and "4" of the required number of frames B1. ideal1 corresponds to the required number of frames B1 of "5", and the target transmittance TR target The transmittance TR of the electronic ND filter 58 is currently set to TR current , multiple ideal transmittances TR ideal1 , and target transmittance TR target The current transmittance TRcurrent , multiple ideal transmittances TR ideal1 , and target transmittance TR target is the current transmittance TR current to target transmittance TR target In the example shown in Figure 7, the current transmittance TR current , multiple ideal transmittances TR ideal1 , and target transmittance TR target However, the required number of frames B1 changes monotonically from "0" to "5".

[0102] Current transmittance TR current Split Exposure EX div1 Target Exposure EX target The monotonous change in exposure of frame 80 over the period is a change in the current transmittance TR with the shutter speed SP, sensitivity SE, and aperture value FV fixed. current , multiple ideal transmittances TR ideal1 , and target transmittance TR target , the current transmittance TR current to target transmittance TR target This is achieved by monotonically varying the current transmittance TR current , multiple ideal transmittances TR ideal1 , and target transmittance TR target , the current transmittance TR current to target transmittance TR target As an example of monotonically changing the transmittance over current , multiple ideal transmittances TR ideal1 , and target transmittance TR target , the current transmittance TR current to target transmittance TR target For example, the amount of change may be constant between frames 80.

[0103] The processor 64 outputs a plurality of split exposures EX for the exposure of a plurality of frames 80 obtained by capturing images for live view images within the change time T1. div1 For example, the processor 64 controls the application of the corresponding split exposure EX for each frame. div1is set in the imaging device 10, and then the imaging device 10 is made to capture an image. div1 The setting is, for example, a split exposure EX for the electronic ND filter 58 while maintaining the shutter speed SP, aperture value FV, and sensitivity SE. div1 In other words, the transmittance TR is set to a value that can realize the divided exposure EX calculated for each frame 80. div1 The transmittance TR of the electronic ND filter 58 is controlled while maintaining the shutter speed SP, aperture value FV, and sensitivity SE so that live view image capturing is performed at .

[0104] On the other hand, as shown in FIG. 8, for example, when the change time T1 exceeds the threshold value TH1, that is, when the transmittance TR of the electronic ND filter 58 becomes equal to the current transmittance TR current Target Exposure EX target If the time required for the transmittance TR of the electronic ND filter 58 to change to is not within the ideal time, the processor 64 sets the transmittance TR of the electronic ND filter 58 to a transmittance TR within the change time T1, which is a transmittance TR whose change time T1 falls within a range equal to or less than the threshold TH1. InTime1 is calculated using a transmittance calculation formula 94. The transmittance calculation formula 94 is calculated using a change time T1, a threshold value TH1, a current transmittance TR current , and target transmittance TR target is used as an independent variable, and the time-varying transmittance TR InTime1 is an arithmetic expression with as the dependent variable.

[0105] The processor 64 calculates the transmittance TR of the electronic ND filter 58 as the current transmittance TR current Change in transmittance TR within time InTime1 Target transmittance TR target The change time T2, which is the time required to change the current transmittance TR to current , the change in transmittance over time TR InTime1 , and target transmittance TR target is an arithmetic expression with the independent variable and the change time T2 as the dependent variable.

[0106] Based on the change time T2 and the frame rate FR, the processor 64 calculates the required number of frames B2, which is the number of frames required for the change time T2 to pass. For example, the required number of frames B2 is calculated by "(change time T2) x (frame rate FR)".

[0107] The processor 64 determines the number of frames required, B2, and the target exposure, EX. target , and current transmittance TR current Based on multiple split exposure EX div1 Calculate multiple split exposures EX div1 The calculation of is performed using the divided exposure calculation formula 98. The divided exposure calculation formula 98 is based on the number of required frames B2, the target exposure EX target , and current transmittance TR current is used as an independent variable, and multiple split exposures EX div1 is a calculation formula with the dependent variable as follows: div1 The number of frames required is equivalent to the number of split exposures in B2. div1 is.

[0108] The processor 64 generates a plurality of split exposures EX div1 and based on the known transmittance, multiple ideal transmittances TR ideal1 and multiple real transmittance TR real1 Here, the known transmittance is the current transmittance TR current , target transmittance TR target , and the time-varying transmittance TR InTime1 Refers to multiple ideal transmittances TR ideal1 and multiple real transmittance TR real1 The transmittance calculation formula 100 is used to calculate the transmittance of a plurality of divided exposures EX div1 , current transmittance TR current , target transmittance TR target , and the time-varying transmittance TR InTime1 is used as an independent variable, and multiple ideal transmittances TR ideal1 and multiple real transmittance TR real1 is an arithmetic expression with as the dependent variable.

[0109] Multiple Reality Transmittance TR real1is the time when the change time T2 is equal to or less than the threshold value TH1 and the transmittance TR of the electronic ND filter 58 is equal to the current transmittance TR current to target transmittance TR target The actual change is a change in the transmittance TR of the electronic ND filter 58 from the current transmittance TR current to target transmittance TR target This refers to a change in the transmittance TR that can be achieved within a time period equal to or shorter than the threshold value TH1. When the transmittance TR of the electronic ND filter 58 is actually changed, the current transmittance TR of the electronic ND filter 58 is changed to the current to target transmittance TR target Since priority is given to completing the change to within the time period equal to or shorter than the threshold value TH1, the transmittance TR of the electronic ND filter 58 does not change monotonically at a constant rate.

[0110] When the change time T1 exceeds the threshold TH1 and imaging for a live view image is performed, a plurality of actual transmittances TR real1 is set for the electronic ND filter 58. This is because, when imaging for a live view image is performed, even if the change time T1 exceeds the threshold TH1, multiple ideal transmittances TR ideal1 When set, the current transmittance TR current to target transmittance TR target This is because the change to the threshold value TH1 is not completed within a time period equal to or shorter than the threshold value TH1.

[0111] In the example shown in FIG. 8, when the change time T2 is equal to or less than the threshold value TH1 and the transmittance TR of the electronic ND filter 58 is equal to the current transmittance TR current to target transmittance TR target Multiple transmittances TR that realistically change to multiple real transmittances TR real1 As an example, when the change time T2 is equal to or less than the threshold value TH1 and the current transmittance TR current Change in transmittance TR within time InTime1 Target transmittance TR target In the example shown in FIG. 8, the current transmittance TR current and target transmittance TR targetBetween these, the transmittance TR within the change time that makes the change time T2 equal to or less than the threshold value TH1 is InTime1 is defined. Multiple real transmittances TR real1 is the current transmittance TR current and the change in transmittance TR InTime1 That is, in the example shown in FIG. current Change in transmittance TR within time InTime1 A plurality of transmittances TR that change monotonically over time (for example, a plurality of transmittances TR that change linearly) are expressed as a transmittance within a change time TR InTime1 Multiple real transmittance TRs, including real1 It is defined as follows.

[0112] Current transmittance TR current and multiple real transmittance TR real1 is the current transmittance TR current Change in transmittance TR within time InTime1 In the example shown in Figure 8, the current transmittance TR current and multiple real transmittance TR real1 However, the current transmittance TR current Change in transmittance TR within time InTime1 It changes linearly over

[0113] The processor 64 calculates the transmittance TR of the electronic ND filter 58 as the current transmittance TR current , multiple real transmittance TR real1 , and target transmittance TR target However, if the transmittance TR of the electronic ND filter 58 is changed to the current transmittance TR while the shutter speed SP, the aperture value FV, and the sensitivity SE are maintained, current , multiple real transmittance TR real1 , and target transmittance TR target , the transmittance TR of the electronic ND filter 58 changes to the current transmittance TR while maintaining the shutter speed SP, the aperture value FV, and the sensitivity SE. current , multiple ideal transmittances TR ideal1 , and target transmittance TR target The change in brightness between frames 80 will be larger than if the brightness were to change according to the

[0114] Therefore, in the first embodiment, the transmittance TR of the electronic ND filter 58 is set to the current transmittance TR current , multiple real transmittance TR real1 , and target transmittance TR target Even if the transmittance TR of the electronic ND filter 58 changes according to the current transmittance TR while maintaining the shutter speed SP, the aperture value FV, and the sensitivity SE, current , multiple ideal transmittances TR ideal1 , and target transmittance TR target In order to change the brightness between frames 80 at the same level as when it changes according to real1 and multiple ideal transmittances TR ideal1 The difference δ1 in exposure between the frames 80 is calculated. The difference δ1 is an index showing the magnitude of the change in brightness between the frames 80. In other words, the difference δ1 is the degree of deviation from the ideal brightness of the frame 80 (i.e., the actual transmittance TR real1 The exposure and ideal transmittance TR achieved by ideal1 This represents the degree to which the exposure achieved by the

[0115] Since exposure is defined by the shutter speed SP, the aperture value FV, and the sensitivity SE in addition to the transmittance TR of the electronic ND filter 58, the difference δ1 can be made zero by adjusting the shutter speed SP, the aperture value FV, and / or the sensitivity SE. current , multiple real transmittance TR real1 , and target transmittance TR target Supports multiple split exposures EX div1 (i.e., current transmittance TR current to target transmittance TR target Each split exposure EX div1 In other words, the processor 64 adjusts the current transmittance TR by complementing the difference δ1 with the shutter speed SP, the aperture value FV, and / or the sensitivity SE. current , multiple real transmittance TR real1, and target transmittance TR target Supports multiple split exposures EX div1 , the current transmittance TR current , multiple ideal transmittances TR ideal1 , and target transmittance TR target Supports multiple split exposures EX div1 In other words, for each frame 80 included in the required number of frames B2, the shutter speed SP, the aperture value FV, and / or the sensitivity SE are adjusted to match the actual transmittance TR real1 Split exposure achieved by EX div1 , the ideal transmittance TR ideal1 Split exposure achieved by EX div1 The difference δ1 is adjusted using an adjustment value corresponding to the difference δ1 (for example, an adjustment value determined according to the difference δ1) so as to achieve the above.

[0116] The transmittance TR of the electronic ND filter 58 is a plurality of actual transmittance TRs. real1 When live view image capturing is performed using the above, for example, the difference δ1 is compensated for by adjusting the sensitivity SE with adjustment values ​​α1 to α4 for adjusting the sensitivity SE, as shown in Fig. 10. In this way, by adjusting the sensitivity SE with adjustment values ​​α1 to α4 according to the difference δ1, the transmittance TR of the electronic ND filter 58 is adjusted to the current transmittance TR current , multiple real transmittance TR real1 , and target transmittance TR target Even if the transmittance TR of the electronic ND filter 58 is changed according to the above, the shutter speed SP, the aperture value FV, and the sensitivity SE are maintained, and a plurality of actual transmittance TRs are used. real1 Split exposure EX at the same level as when using div1 is realized.

[0117] Each of the adjustment values ​​α1 to α4 is uniquely determined according to the difference δ1 calculated for each frame 80. For example, the adjustment values ​​α1 to α4 are calculated using an adjustment value calculation formula 102 in which the difference δ1 is an independent variable and the adjustment value for adjusting the sensitivity SE is a dependent variable. Note that while an example in which the sensitivity SE is adjusted according to the difference δ1 has been given here, this is merely an example, and the shutter speed SP and / or the aperture value FV may also be adjusted according to the difference δ1. In this case, too, the adjustment values ​​for the shutter speed SP and / or the aperture value FV may be calculated using a calculation formula similar to the adjustment value calculation formula 102.

[0118] When live view image capturing is performed within the change time T2, the processor 64 sets the sensitivity SE adjusted in accordance with the difference δ1 calculated for each frame 80 as described above, the shutter speed SP determined for each frame 80, and the aperture value FV determined for each frame 80 for the image capturing device 10. The processor 64 also sets the current transmittance TR current , multiple real transmittance TR real1 , and target transmittance TR target is set as the transmittance TR of the electronic ND filter 58. In this way, in the imaging for the live view image within the change time T2, the sensitivity SE adjusted in accordance with the difference δ1 calculated for each frame 80 as described above, the shutter speed SP determined for each frame 80, the aperture value FV determined for each frame 80, the current transmittance TR current , multiple real transmittance TR real1 , and target transmittance TR target By setting the multiple frames 80, multiple split exposures EX div1 applies.

[0119] In the first embodiment, imaging for live view images is an example of "imaging by an imaging device" according to the present disclosure. Also, in the first embodiment, the frame rate FR is an example of "default frame rate" according to the present disclosure.

[0120] In the examples shown in FIGS. 6 to 10, the current aperture value FV currentIn the above example, the processor 64 controls the exposure applied to a plurality of frames 80 to change monotonically when the current aperture value FV is maintained. current Target aperture FV target , the processor 64 performs control to keep the exposure applied to a plurality of frames 80 constant, as shown in FIGS. 11 to 25 as an example.

[0121] 11, the processor 64 determines whether an aperture value change instruction has been given to the image capture device 10. If an aperture value change instruction has been given to the image capture device 10, the processor 64 changes the aperture value FV of the aperture 40C to the current aperture value FV current to target aperture FV target The control to change to is initiated by the processor 64.

[0122] As an example, as shown in FIG. 11, the aperture value FV of the aperture 40C is set to the current aperture value FV current to target aperture FV target When changing the aperture value FV to , the processor 64 adjusts the change amount of the aperture value FV (here, as an example, the current aperture value FV current to target aperture FV target The electronic ND filter 58 is then checked to see if it is possible to change the transmittance TR of the electronic ND filter 58 to a value that can compensate for the brightness that changes with the change in aperture value FV (in other words, whether the exposure difference corresponding to the change in aperture value FV can be compensated for by changing the transmittance TR of the electronic ND filter 58). In the first embodiment, the transmittance TR of the electronic ND filter 58 is an example of the "transmittance of an electronic neutral density filter" according to the present disclosure.

[0123] 11 to 13 show the steps of changing the aperture value FV of the aperture 40C to the current aperture value FV when the electronic ND filter 58 cannot follow the change in the aperture value FV. current to target aperture FV target An example of the control content for changing the value to the value shown in FIG.

[0124] As an example, as shown in FIG. 11, when the electronic ND filter 58 cannot follow the change in the aperture value FV, the processor 64 current , target aperture value FV target , current transmittance TR current , and Target Exposure EX target Based on this, the target sensitivity SE target and target shutter speed SP target Calculate the target sensitivity SE target and other exposure factors (for example, the current aperture value FV current , target aperture value FV target , current transmittance TR current , and target shutter speed SP target ) with Target Exposure EX target Target shutter speed SP target (Here, as an example, the current aperture value FV current , target aperture value FV target , current transmittance TR current , and target sensitivity SE target ) with Target Exposure EX target This refers to the shutter speed SP that can be realized.

[0125] Target Sensitivity SE target and target shutter speed SP target The calculation of is performed using the exposure factor calculation formula 104. The exposure factor calculation formula 104 is current , target aperture value FV target , current transmittance TR current , and Target Exposure EX target is the independent variable, and the target sensitivity SE target and target shutter speed SP target is a dependent variable. In the first embodiment, the exposure factor refers to one of the factors that define exposure. Exposure is defined by multiple exposure factors, including transmittance TR, aperture value FV, sensitivity SE, and shutter speed SP.

[0126] Also, change the aperture value FV of the aperture 40C to the current aperture value FV current to target aperture FV targetWhen changing to the current aperture value FV current and target aperture value FV target Based on this, the driving time of the aperture 40C, i.e., the aperture driving time T FV Calculate the aperture drive time T FV The aperture value FV of aperture 40C is the current aperture value FV current to target aperture FV target The aperture drive time T FV The calculation of is performed using the aperture drive time calculation formula 106. The aperture drive time calculation formula 106 is current and target aperture value FV target is the independent variable, and the aperture drive time T FV In the first embodiment, the aperture driving time T FV is an example of "aperture drive time" according to the present disclosure.

[0127] As an example, as shown in FIG. 12, the processor 64 determines the aperture driving time T FV and the frame rate FR, the aperture drive time T FV The number of frames corresponding to the aperture drive time T FV The required number of frames B3 is calculated as the number of frames obtained by capturing live view images during the elapse of the aperture drive time T FV )×(frame rate FR)”. In the first embodiment, the required number of frames B3 is an example of the “second number of frames”, “fourth number of frames”, and “sixth number of frames” according to the present disclosure.

[0128] Processor 64 requires B3 frames and FV current , and target aperture value FV target Multiple predicted aperture values ​​FV based on pred0 Calculate multiple predicted aperture values ​​FV pred0 Each of these is the current aperture value FV current to target aperture FV target The predicted aperture value FV is a value that is used for each frame 80 obtained until thepred0 The current aperture value FV current and target aperture value FV target Multiple predicted aperture values ​​FV pred0 The calculation of is performed using the aperture value calculation formula 107. The aperture value calculation formula 107 is based on the number of frames required B3, the current aperture value FV current , and target aperture value FV target is used as an independent variable, and multiple predicted aperture values ​​FV pred0 is an arithmetic expression with as the dependent variable.

[0129] The processor 64 currently calculates the transmittance TR current , current sensitivity SE current , current shutter speed SP current , and multiple predicted aperture values ​​FV pred0 Based on multiple split exposure EX div2 Calculate the current sensitivity SE current is the sensitivity SE currently set for the image capture device 10. Current shutter speed SP current is the shutter speed SP currently set for the image capture device 10. div2 The number of predicted aperture values ​​FV pred0 The number of split exposures is the same as the number of EX div2 Each of these is the aperture drive time T FV The exposure applied to each of the frames 80 obtained during the time period, current , current sensitivity SE current , current shutter speed SP current , and multiple predicted aperture values ​​FV pred0 This is the exposure predicted from multiple split exposures. div2 The calculation of is performed using the divided exposure calculation formula 108. The divided exposure calculation formula 108 calculates the current transmittance TR current , current sensitivity SE current , current shutter speed SP current , and multiple predicted aperture values ​​FV pred0 is used as an independent variable, and multiple split exposures EX div2 is an arithmetic expression with as the dependent variable.

[0130] The processor 64 determines the target exposure EXtarget and multiple split exposure EX div2 Based on multiple exposure differences EX diff Calculate multiple exposure differences EX diff Each of these targets EX target and multiple split exposure EX div2 Here, the difference is shown as an example, but it can also be a ratio, and the target exposure EX target and Split Exposure EX div2 Any indicator showing the degree of difference from the original image may be used.

[0131] The processor 64 generates a plurality of exposure differentials EX diff The number of the sensitivity adjustment values ​​Δa is calculated based on the exposure difference EX diff The number of the shutter speed adjustment values ​​Δb is the same as the number of the exposure differences EX diff The multiple sensitivity adjustment values ​​Δa are the same as the aperture drive time T FV In order to obtain the sensitivity SE necessary to keep the brightness of the plurality of frames 80 obtained during the time lapse, the current sensitivity SE is calculated. current The shutter speed adjustment value Δb is used to adjust the aperture drive time T FV The current shutter speed SP is calculated to obtain the shutter speed SP necessary to keep the brightness of the plurality of frames 80 obtained during the elapse of time constant. current The sensitivity adjustment values ​​Δa and shutter speed adjustment values ​​Δb are calculated using an adjustment value calculation formula 109. The adjustment value calculation formula 109 calculates the sensitivity adjustment values ​​Δa and shutter speed adjustment values ​​Δb by calculating the sensitivity adjustment values ​​Δa and shutter speed adjustment values ​​Δb. diff is an arithmetic expression in which the independent variable is a plurality of sensitivity adjustment values ​​Δa and a plurality of shutter speed adjustment values ​​Δb are dependent variables.

[0132] The processor 64 calculates the current sensitivity SE using the plurality of sensitivity adjustment values ​​Δa. current This allows for the same number of adjusted sensitivities SE as the number of sensitivity adjustment values ​​Δa. Also, the processor 64 adjusts the current sensitivity SE using the multiple shutter speed adjustment values ​​Δb. currentAs a result, the same number of adjusted shutter speeds SP as the number of shutter speed adjustment values ​​Δb are obtained.

[0133] Aperture drive time T FV When live view image capturing is performed within the predetermined time, the exposure of the plurality of frames 80 obtained by capturing the live view image is performed at a current transmittance TR current and aperture drive time T FV and a plurality of sensitivities SE adjusted with a plurality of sensitivity adjustment values ​​Δa obtained based on the above, a target sensitivity SE target , a plurality of shutter speeds SP adjusted by a plurality of shutter speed adjustment values ​​Δb, a target shutter speed SP target , and multiple predicted aperture values ​​FV pred0 , and current transmittance TR current For example, as shown in FIG. 13, the processor 64 determines the aperture drive time T FV Within, the current transmittance TR current , multiple sensitivities SE adjusted by multiple sensitivity adjustment values ​​Δa, target sensitivity SE target , a plurality of shutter speeds SP adjusted by a plurality of shutter speed adjustment values ​​Δb, a target shutter speed SP target , and multiple predicted aperture values ​​FV pred0 The imaging device 10 is caused to capture an image for a live view image with exposure using the aperture drive time T FV The exposure of the multiple frames 80 obtained by capturing live view images within the frame is kept constant.

[0134] In the examples shown in FIGS. 11 to 13, when the electronic ND filter 58 cannot track the change in the aperture value FV, the aperture value FV of the aperture 40C is set to the current aperture value FV current to target aperture FV target 14 to 25 show an example of the control content for changing the aperture value FV of the aperture 40C to the current aperture value FV when the change in the aperture value FV can be tracked by the electronic ND filter 58. current to target aperture FV target1 shows an example of the control content for changing the aperture value FV of the aperture 40C to the current aperture value FV when the change in the aperture value FV can be tracked by the electronic ND filter 58. current to target aperture FV target In the control to change the exposure of a plurality of frames 80 obtained by capturing images for live view images, the transmittance TR and the aperture drive time T FV The control is based on the following.

[0135] As an example, as shown in FIG. 14, when the electronic ND filter 58 can follow the change in the aperture value FV, the processor 64 current and target aperture value FV target Based on the aperture drive time T FV Calculate the aperture drive time T FV is calculated in the same manner as in the example shown in FIG.

[0136] If the change in aperture value FV can be followed by the electronic ND filter 58, the processor 64 sets the target exposure EX target , target aperture value FV target , and a target exposure EX based on a plurality of current exposure factors. target Target transmittance TR corresponding to target Here, the current exposure factor means an exposure factor that defines the current exposure. The multiple current exposure factors used here include the current transmittance TR current , current aperture value FV current , current sensitivity SE current , and the current shutter speed SP current The target transmittance TR target The calculation of the target transmittance is performed using a target transmittance calculation formula 110. The target transmittance calculation formula 110 is target , target aperture value FV target , and multiple current exposure factors are used as independent variables, and the target transmittance TR target is an arithmetic expression with as the dependent variable.

[0137] The processor 64 calculates the target transmittance TR target and current transmittance TR currentThe change time T1 is calculated based on the above formula: The change time T1 is calculated in the same manner as in the example shown in FIG.

[0138] In the first embodiment, when the electronic ND filter 58 can follow the change in the aperture value FV, the aperture drive time T FV and the change time T1 shown in FIG. div3 (See Figure 18) or multiple split exposures EX div4 (See Figure 23) is the aperture drive time T FV The exposure of the plurality of frames 80 is controlled by applying the control to the exposure of the plurality of frames 80 obtained by capturing live view images during the time that elapses. An example of the control content for achieving this is shown in Figs. 15 to 25. Figs. 15 to 20 show the exposure of the plurality of divided exposure EX div3 (See Figure 18) is the aperture drive time T FV 21 to 25 show examples in which the exposure of a plurality of frames 80 is controlled by applying the exposure control signal to the exposure of a plurality of frames 80 obtained by capturing live view images during the elapse of time. div4 (See Figure 23) is the aperture drive time T FV 10 shows an example of a form in which the exposure of a plurality of frames 80 is controlled by applying the exposure control signal to the exposure of a plurality of frames 80 obtained by capturing images for live view images while the exposure control signal is being applied to the exposure of a plurality of frames 80.

[0139] As an example, as shown in FIG. 15, the processor 64 determines the aperture driving time T FV The threshold value TH2 is the time when the transmittance TR of the electronic ND filter 58 is equal to or exceeds the current transmittance TR. current to target transmittance TR target The ideal waiting time until the target exposure EX changes to the target exposure EX under the condition that the shutter speed SP and sensitivity SE are fixed. target (the ideal time it takes to achieve this) and the aperture value FV is the current aperture value FV current to target aperture FV targetThis is a value determined based on the ideal waiting time until the transmittance TR of the electronic ND filter 58 changes to the current transmittance TR current to target transmittance TR target The ideal waiting time until the aperture value FV changes to the current aperture value FV current to target aperture FV target An example of a value determined based on an ideal waiting time until the transmittance TR of the electronic ND filter 58 changes to the current transmittance TR current to target transmittance TR target The ideal upper limit of the waiting time until the current aperture value FV current to target aperture FV target The threshold value TH2 may be the larger of the upper limits of the ideal waiting time until the transmittance TR of the electronic ND filter 58 changes to the threshold value TH2. The threshold value TH2 may be a fixed value, or a variable value that is changed in accordance with a given instruction or various conditions. Furthermore, the threshold value TH2 may be a time determined by the user, a time determined according to the type of imaging mode, or a time specified within a range of several percent to several tens of percent of the maximum time obtained from a table that defines the time over which the transmittance TR of the electronic ND filter 58 changes (for example, a time equivalent to 50% of the maximum time obtained from a table that defines the time over which the transmittance TR of the electronic ND filter 58 changes).

[0140] Aperture drive time T FV When both the change time T1 and the change time T2 exceed the threshold value TH2, the processor 64 performs the first control 112, and the aperture drive time T FV And / if the change time T1 is equal to or less than the threshold value TH2, the processor 64 performs the second control 114. In the first embodiment, the threshold value TH2 is an example of the "first threshold value," "third threshold value," "fifth threshold value," and "seventh threshold value" according to the present disclosure. In the first embodiment, the first control 112 is an example of the "first control" according to the present disclosure, and the second control 114 is an example of the "second control" according to the present disclosure.

[0141] 15 to 20 show an example of the contents of the first control 112. The first control 112 includes a current transmittance TR currentto target transmittance TR target The time required for the change to FV There is control to make it within the current transmittance TR current to target transmittance TR target The actual change time to the aperture drive time T FV and multiple split exposures EX div3 (see FIG. 18) to the exposure of a plurality of frames 80 obtained by capturing images for live view images.

[0142] To realize the first control 112, as shown in FIG. 16 as an example, the processor 64 calculates the aperture drive time T FV (See Figure 14), change time T1 (See Figure 14), current transmittance TR current , and target transmittance TR target Based on the transmittance TR during the driving time InTime2 Calculate the transmittance during driving time TR InTime2 is the current transmittance TR current and target transmittance TR target The transmittance TR of the electronic ND filter 58 is between current to target transmittance TR target The time required for the change to FV The transmittance TR of the electronic ND filter 58 is the current transmittance TR current to target transmittance TR target The time required to change the transmittance of the electronic ND filter 58 from the current transmittance TR current Transmittance during driving time TR InTime2 Target transmittance TR target By changing the transmittance during the driving time, InTime2 The transmittance during operation time TR InTime2 The calculation of is performed using the transmittance calculation formula 116. The transmittance calculation formula 116 is obtained by calculating the aperture driving time T FV , change time T1, current transmittance TR current , and target transmittance TR target is used as an independent variable, and the transmittance during driving time TR InTime2 In the first embodiment, the transmittance within the driving time TRInTime2 are examples of the "third transmittance" and "fourth transmittance" according to the present disclosure.

[0143] The processor 64 determines the aperture drive time T FV and the frame rate FR, the required number of frames B3 is calculated in the same manner as in the example shown in FIG.

[0144] Processor 64 requires B3 frames and FV current , and target aperture value FV target Multiple predicted aperture values ​​FV based on pred1 Calculate multiple predicted aperture values ​​FV pred1 is a set of predicted aperture values ​​FV pred0 and is calculated in the same manner as in the example shown in FIG.

[0145] As an example, as shown in FIG. 17, the processor 64 calculates the transmittance within the driving time TR InTime2 , current transmittance TR current , and target transmittance TR target Based on this, the transmittance TR of the electronic ND filter 58 is calculated based on the aperture driving time T FV Current transmittance TR current to target transmittance TR target In other words, the change time T3 is calculated by changing the transmittance TR of the electronic ND filter 58 to the current transmittance TR current Transmittance during driving time TR InTime2 Target transmittance TR target The change time T3 is calculated using a change time calculation formula 118. The change time calculation formula 118 calculates the transmittance within the driving time TR InTime2 , current transmittance TR current , and target transmittance TR target is an arithmetic expression with an independent variable and a change time T3 as a dependent variable. Note that in the first embodiment, the change time T3 is an example of the "actual change time" according to the present disclosure.

[0146] Based on the change time T3 and the frame rate FR, the processor 64 calculates the number of frames corresponding to the change time T3, i.e., the required number of frames B4, which is the number of frames required while the change time T3 elapses. For example, the required number of frames B4 is calculated by "(change time T3) x (frame rate FR)". Note that in the first embodiment, the required number of frames B4 is an example of the "first number of frames" according to the present disclosure.

[0147] The processor 64 determines the number of frames required, B4, and the target exposure, EX. target , target aperture value FV target , current aperture value FV current , current transmittance TR current , current sensitivity SE current , current shutter speed SP current , and multiple predicted aperture values ​​FV pred1 Based on multiple predicted transmittance TR pred1 Calculate multiple predicted transmittances TR pred1 is the current transmittance TR within the change time T3 current to target transmittance TR target Here, the realistic change is defined as the process by which the transmittance TR of the electronic ND filter 58 changes from the current transmittance TR current to target transmittance TR target Change to narrow the drive time T FV When the transmittance TR of the electronic ND filter 58 is actually changed, the current transmittance TR of the electronic ND filter 58 is changed. current to target transmittance TR target Change to narrow the drive time T FV Since it is a priority to complete the process within the time limit, the transmittance TR of the electronic ND filter 58 is currently set to TR current to target transmittance TR target It does not change monotonically at a constant rate over time.

[0148] In addition, multiple predicted transmittance TR pred1 are exposures applied to each of the multiple frames 80 obtained during the change time T3, and include the required number of frames B4, the target exposure EXtarget , target aperture value FV target , current aperture value FV current , current transmittance TR current , current sensitivity SE current , current shutter speed SP current , and multiple predicted aperture values ​​FV pred1 is the transmittance TR predicted from

[0149] Multiple predicted transmittance TR pred1 The calculation of is performed using a predicted transmittance calculation formula 119. The predicted transmittance calculation formula 119 is based on the required frame number B4, the target exposure EX target , target aperture value FV target , current aperture value FV current , current transmittance TR current , current sensitivity SE current , current shutter speed SP current , and multiple predicted aperture values ​​FV pred1 is used as an independent variable, and multiple predicted transmittances TR pred1 is a calculation formula with the dependent variable as follows: pred1 are multiple aperture values ​​FV calculated based on the required number of frames B3, and therefore multiple predicted transmittances TR pred1 can also be said to be a plurality of transmittances TR determined based on the required number of frames B3 and the required number of frames B4.

[0150] The required number of frames B4 is calculated based on the change time T3. The change time T3 is calculated by dividing the current transmittance TR of the electronic ND filter 58 by the current transmittance TR current Transmittance during driving time TR InTime2 Target transmittance TR target Therefore, the time required for the multiple predicted transmittances TR pred1 is the current transmittance TR current and transmittance during operation time TR InTime2 It can also be said that the transmittances are determined based on the above.

[0151] In the first embodiment, a plurality of predicted transmittances TR pred1 is an example of a "plurality of first actual transmittances" according to the present disclosure.

[0152] As an example, as shown in FIG. 18, the processor 64 sets the larger of the required number of frames B3 and the required number of frames B4 as the maximum number of frames B. max1 The maximum number of frames is B max1 and Target Exposure EX target and based on multiple split exposure EX div3 Here, in order to maintain a constant brightness of the multiple frames 80 obtained by capturing images for live view images, multiple split exposures EX div3 are equivalent to each other. That is, the processor 64 calculates the target exposure EX target The same exposure as the maximum number of frames B max1 Split exposure EX for each of the 80 frames div3 Assign as.

[0153] Here, the maximum number of frames B max1 The maximum number of frames is B max1 Alternatively, the average value of the required number of frames B3 and the required number of frames B4 may be used.

[0154] The processor 64 generates a plurality of split exposures EX div3 , multiple predicted transmittance TR pred1 , and multiple predicted aperture values ​​FV pred1 Based on multiple predicted sensitivity SE pred1 and a plurality of predicted shutter speeds SP pred1 Calculate.

[0155] Split exposure EX div3 is defined by multiple exposure factors. Split exposure EX div3 The multiple exposure factors that define the predicted transmittance TR pred1 , predicted aperture value FV pred1 , prediction sensitivity SE pred1 , and predicted shutter speed SP pred1 Refers to...

[0156] Multiple Split Exposure EX div3 , multiple predicted transmittance TR pred1 , and multiple predicted aperture values ​​FV pred1Multiple predicted sensitivities SE calculated based on pred1 Each of these is the current aperture value FV current to target aperture FV target This is a predicted value of the sensitivity SE used for each frame 80 obtained up to the point where multiple split exposures EX div3 , multiple predicted transmittance TR pred1 , and multiple predicted aperture values ​​FV pred1 A plurality of predicted shutter speeds SP calculated based on pred1 is the current aperture value FV current to target aperture FV target This is a predicted value of the shutter speed SP to be used for each frame 80 obtained up to the point where the shutter speed SP is reached.

[0157] Multiple prediction sensitivity SE pred1 and a plurality of predicted shutter speeds SP pred1 The calculation of is performed using the exposure factor calculation formula 120. The exposure factor calculation formula 120 is used to calculate the exposure factor EX div3 , multiple predicted transmittance TR pred1 , and multiple predicted aperture values ​​FV pred1 are used as independent variables, and multiple prediction sensitivity SE pred1 and a plurality of predicted shutter speeds SP pred1 is an arithmetic expression with as the dependent variable.

[0158] In this way, multiple prediction sensitivities SE pred1 and a plurality of predicted shutter speeds SP pred1 Multiple Split Exposure EX div3 It is calculated based on multiple predicted sensitivities SE pred1 and a plurality of predicted shutter speeds SP pred1 Multiple split exposures EX used to calculate div3 is the target exposure EX target Therefore, multiple predicted sensitivities SE pred1 and a plurality of predicted shutter speeds SP pred1 is the target exposure EX target It can also be said that this is an exposure factor that is set in the imaging device 10 in accordance with the image.

[0159] When live view image capturing is performed within the change time T3, the exposure of the plurality of frames 80 obtained by capturing the live view image is a plurality of divided exposures EX div3 Defines multiple predicted transmittances TR pred1 , multiple predicted aperture values ​​FV pred1 , multiple prediction sensitivity SE pred1 , a plurality of predicted shutter speeds SP pred1 It is determined by:

[0160] For example, as shown in FIG. 19, the processor 64 calculates a plurality of predicted transmittances TR within the change time T3. pred1 , multiple predicted aperture values ​​FV pred1 , multiple prediction sensitivity SE pred1 , a plurality of predicted shutter speeds SP pred1 As a result, the image capturing device 10 is caused to capture live view images using the exposure using the multiple divided exposures EX div3 As a result, the exposure of the multiple frames 80 obtained by capturing live view images while the change time T3 has elapsed is kept constant.

[0161] As an example, as shown in FIG. 20, if the first control 112 described above is not performed, the aperture drive time T FV When both the current transmittance TR and the change time T1 exceed the threshold value TH2, the required number of frames B3 exceeds the target number of frames A1, which is the number of frames required until the threshold value TH2 elapses. current and target transmittance TR target Depending on the relationship between the transmittance TR of the electronic ND filter 58 and the current transmittance TR current to target transmittance TR target Change to aperture drive time T FV This is because the change time T1 is longer than the aperture drive time T FVTherefore, in the first embodiment, the first control 112 described above is performed by the processor 64, and as shown in FIG. 20 as an example, the transmittance TR of the electronic ND filter 58 is set to the current transmittance TR current From the transmittance during the driving time, TR InTime2 Multiple predicted transmittances, including TR pred1 (i.e., the current transmittance TR of the electronic ND filter 58) current to target transmittance TR target Change to narrow the drive time T FV The target transmittance TR is reached through multiple transmittances TR (defined to meet the target transmittance TR) target As a result, the current transmittance TR of the electronic ND filter 58 is changed to current to target transmittance TR target Change to narrow the drive time T FV It will be possible to make it in time.

[0162] Moreover, the transmittance TR of the electronic ND filter 58 is set to the current transmittance TR current to target transmittance TR target Target exposure EX target To maintain the above, multiple predicted transmittances TR pred1 A plurality of exposure factors including (see FIGS. 16 to 19) are determined, and the plurality of exposure factors are applied to the exposure of a plurality of frames 80 obtained by performing imaging for a live view image within the change time T3. This makes it possible to maintain constant brightness for a plurality of frames 80 obtained by performing imaging for a live view image within the change time T3.

[0163] 21 to 50 show examples of the contents of the second control 114. The second control 114 includes a current transmittance TR current to target transmittance TR target The ideal time to change to and the aperture drive time T FV and multiple split exposures EX div4 to the exposure of a plurality of frames 80 obtained by capturing images for live view images.

[0164] To realize the second control 114, as shown in FIG. 21 for example, the processor 64 FV The required number of frames B3 is calculated based on the required number of frames B3, the current aperture value FV, and the frame rate FR. The required number of frames B3 is calculated in the same manner as in the example shown in FIG. 12. current , and target aperture value FV target Based on the multiple predicted aperture values ​​FV pred2 Calculate multiple predicted aperture values ​​FV pred2 In the example shown in FIG. 16, multiple predicted aperture values ​​FV pred2 is calculated in the same manner as

[0165] As an example, as shown in Fig. 22, the processor 64 calculates the required number of frames B1 based on the change time T1 and the frame rate FR. The required number of frames B1 is the number of frames corresponding to the change time T1, i.e., the number of frames obtained by capturing live view images while the change time T1 has elapsed. The required number of frames B1 is calculated in a manner similar to the example shown in Fig. 7. Note that in this embodiment, the change time T1 is an example of the "ideal change time" according to the present disclosure, and the required number of frames B1 is an example of the "first number of frames" and "third number of frames" according to the present disclosure.

[0166] The processor 64 determines the number of frames required, B1, and the target exposure, EX. target , target aperture value FV target , current aperture value FV current , current transmittance TR current , current sensitivity SE current , current shutter speed SP current , and multiple predicted aperture values ​​FV pred2 Based on multiple predicted transmittance TR pred2 Calculate multiple predicted transmittances TR pred2 is the current transmittance TR within the change time T1. current to target transmittance TR target This is the transmittance that defines the ideal process of change from

[0167] Multiple predicted transmittance TRpred2 The calculation of is performed using a predicted transmittance calculation formula 122. The predicted transmittance calculation formula 122 is based on the required frame number B1, the target exposure EX target , target aperture value FV target , current aperture value FV current , current transmittance TR current , current sensitivity SE current , current shutter speed SP current , and multiple predicted aperture values ​​FV pred2 is used as an independent variable, and multiple predicted transmittances TR pred2 is a calculation formula with the dependent variable as follows: pred2 are multiple aperture values ​​FV calculated based on the required number of frames B3, and therefore multiple predicted transmittances TR pred2 can be said to be a plurality of transmittances TR determined based on the required number of frames B1 and the required number of frames B3. pred2 is an example of the "plurality of ideal transmittances" according to the present disclosure.

[0168] As an example, as shown in FIG. 23, the processor 64 sets the larger of the required number of frames B1 and the required number of frames B3 as the maximum number of frames B. max2 The maximum number of frames is B max2 and Target Exposure EX target and based on multiple split exposure EX div4 Here, in order to maintain a constant brightness of the multiple frames 80 obtained by capturing images for live view images, multiple split exposures EX div4 are equivalent to each other. That is, the processor 64 calculates the target exposure EX target The same exposure as the maximum number of frames B max2 Split exposure EX for each of the 80 frames div4 Assign as.

[0169] Here, the maximum number of frames B max2 The maximum number of frames is B max2 Alternatively, the average value of the required number of frames B1 and the required number of frames B3 may be used.

[0170] The processor 64 generates a plurality of split exposures EX div4 , multiple predicted transmittance TR pred2 , and multiple predicted aperture values ​​FV pred2 Based on multiple predicted sensitivity SE pred2 and a plurality of predicted shutter speeds SP pred2 Calculate.

[0171] Split exposure EX div4 is defined by multiple exposure factors. Split exposure EX div3 The multiple exposure factors that define the predicted transmittance TR pred2 , predicted aperture value FV pred2 , prediction sensitivity SE pred2 , and predicted shutter speed SP pred2 Refers to...

[0172] Multiple Split Exposure EX div4 , multiple predicted transmittance TR pred2 , and multiple predicted aperture values ​​FV pred2 Multiple predicted sensitivities SE calculated based on pred2 Each of these is the current aperture value FV current to target aperture FV target This is a predicted value of the sensitivity SE used for each frame 80 obtained up to the point where multiple split exposures EX div4 , multiple predicted transmittance TR pred2 , and multiple predicted aperture values ​​FV pred2 A plurality of predicted shutter speeds SP calculated based on pred2 is the current aperture value FV current to target aperture FV target This is a predicted value of the shutter speed SP to be used for each frame 80 obtained up to the point where the shutter speed SP is reached.

[0173] Multiple prediction sensitivity SE pred2 and a plurality of predicted shutter speeds SP pred2 The calculation of is performed using the exposure factor calculation formula 124. The exposure factor calculation formula 124 is used to calculate the exposure factor EX div4 , multiple predicted transmittance TR pred2 , and multiple predicted aperture values ​​FV pred2 are used as independent variables, and multiple prediction sensitivity SE pred2and a plurality of predicted shutter speeds SP pred2 is an arithmetic expression with as the dependent variable.

[0174] In this way, multiple prediction sensitivities SE pred2 and a plurality of predicted shutter speeds SP pred2 Multiple Split Exposure EX div4 It is calculated based on multiple predicted sensitivities SE pred2 and a plurality of predicted shutter speeds SP pred2 Multiple split exposures EX used to calculate div4 is the target exposure EX target Therefore, multiple predicted sensitivities SE pred2 and a plurality of predicted shutter speeds SP pred2 is the target exposure EX target It can also be said that this is an exposure factor that is set in the imaging device 10 in accordance with the image.

[0175] When live view image capturing is performed within the change time T1, the exposure of the plurality of frames 80 obtained by capturing the live view image is a plurality of divided exposures EX div4 Defines multiple predicted transmittances TR pred2 , multiple predicted aperture values ​​FV pred2 , multiple prediction sensitivity SE pred2 , a plurality of predicted shutter speeds SP pred2 It is determined by:

[0176] For example, as shown in FIG. 24, the processor 64 calculates a plurality of predicted transmittances TR within the change time T1. pred2 , multiple predicted aperture values ​​FV pred2 , multiple prediction sensitivity SE pred2 , a plurality of predicted shutter speeds SP pred2 In this way, the image capturing device 10 is caused to capture live view images using the exposure using the multiple divided exposures EX div4 As a result, the exposure of the multiple frames 80 obtained by capturing images for live view images while the change time T1 has elapsed is kept constant.

[0177] In the first embodiment, the second control 114 described above is performed by the processor 64, and as shown in FIG. 25, for example, the aperture value of the aperture 40C is set to the current aperture value FV current to target aperture FV target and the transmittance TR of the electronic ND filter 58 is changed to the current transmittance TR current From this, multiple predicted transmittances TR pred2 (i.e., monotonically varying transmittance TR) along the target transmittance TR target Moreover, the target exposure EX target To maintain the above, multiple predicted transmittances TR pred2 A plurality of exposure factors including (see FIGS. 21 to 24) are determined, and the plurality of exposure factors are applied to the exposure of a plurality of frames 80 obtained by performing imaging for a live view image within the change time T1. This makes it possible to maintain constant brightness for a plurality of frames 80 obtained by performing imaging for a live view image within the change time T1.

[0178] Next, the operation of the imaging device 10 will be described with reference to Figures 26A to 26G. Figures 26A to 26G show the current transmittance TR as the transmittance TR of the electronic ND filter 58. current 26A to 26G show an example of the flow of exposure control processing that is executed by processor 64 on the condition that the exposure calculation start timing has arrived when imaging for a live view image is performed (in other words, the timing that has been specified in advance as the timing for adjusting the exposure of frame 80 obtained by imaging for a live view image has arrived). The flow of exposure control processing shown in FIGS. 26A to 26G is an example of a "control method" according to the present disclosure.

[0179] 26A, first, in step ST10, processor 64 acquires frame 80 generated by capturing an image for a live view image. After the processing of step ST10 is executed, the exposure control processing proceeds to step ST12.

[0180] In step ST12, the processor 64 calculates a photometric value 90 based on the frame 80 acquired in step ST10. After the processing of step ST12 is executed, the exposure control processing proceeds to step ST14.

[0181] In step ST14, the processor 64 calculates the target exposure EX based on the photometric value 90 as the exposure for adjusting the brightness of the frame 80 used to calculate the photometric value 90 to the target brightness. target After the process of step ST14 is executed, the exposure control process proceeds to step ST16.

[0182] In step ST15, the processor 64 determines whether or not an aperture value change instruction has been given to the imaging device 10. If an aperture value change instruction has not been given to the imaging device 10 in step ST15, the determination is negative, and the exposure control processing proceeds to step ST16 shown in Fig. 26B. If an aperture value change instruction has been given to the imaging device 10 in step ST15, the determination is positive, and the exposure control processing proceeds to step ST48.

[0183] In step ST16 shown in FIG. 26B, processor 64 calculates the target exposure EX target Target transmittance TR corresponding to target After the processing of step ST16 is executed, the exposure control processing proceeds to step ST18.

[0184] In step ST18, the processor 64 calculates the current transmittance TR currently set in the electronic ND filter 58. current After the process of step ST18 is executed, the exposure control process proceeds to step ST20.

[0185] In step ST20, the processor 64 sets the transmittance TR of the electronic ND filter 58 to the current transmittance TR current to target transmittance TR targetThe time required for the ideal change to the value, that is, the change time T1, is calculated. After the process of step ST20 is executed, the exposure control process proceeds to step ST22.

[0186] In step ST22, processor 64 determines whether or not change time T1 exceeds threshold value TH1. If change time T1 does not exceed threshold value TH1 in step ST22, the determination is negative, and the exposure control process proceeds to step ST24. If change time T1 exceeds threshold value TH1 in step ST22, the determination is positive, and the exposure control process proceeds to step ST28 shown in FIG. 26C.

[0187] In step ST24, the processor 64 calculates the required number of frames B1 based on the change time T1 and the frame rate FR. After the processing of step ST24 is executed, the exposure control processing proceeds to step ST26.

[0188] In step ST26, the processor 64 calculates the number of frames required B1, the target exposure EX target , and current transmittance TR current Based on multiple split exposure EX div1 After the process of step ST26 is executed, the exposure control process proceeds to step ST42 shown in FIG.

[0189] In step ST28 shown in FIG. 26C, the processor 64 determines the transmittance TR of the electronic ND filter 58 as the transmittance TR within the change time, which is the transmittance TR for which the change time T1 falls within a range equal to or less than the threshold TH1. InTime1 The change time T1, the threshold TH1, and the current transmittance TR current , and target transmittance TR target After the process of step ST28 is executed, the exposure control process proceeds to step ST30.

[0190] In step ST30, the processor 64 sets the transmittance TR of the electronic ND filter 58 to the current transmittance TR current Change in transmittance TR within time InTime1 Target transmittance TRtarget The time required to change the transmittance to the current transmittance TR, i.e., the change time T2, is current , the change in transmittance over time TR InTime1 , and target transmittance TR target After the process of step ST30 is executed, the exposure control process proceeds to step ST32.

[0191] In step ST32, the processor 64 calculates the required number of frames B2 based on the change time T2 and the frame rate FR. After the processing of step ST32 is executed, the exposure control processing proceeds to step ST34.

[0192] In step ST34, the processor 64 calculates the number of frames required B2, the target exposure EX target , and current transmittance TR current Based on multiple split exposure EX div1 After the process of step ST34 is executed, the exposure control process proceeds to step ST36.

[0193] In step ST36, processor 64 generates a plurality of split exposures EX div1 , current transmittance TR current , target transmittance TR target , and the time-varying transmittance TR InTime1 Based on multiple real-world transmittance TR real1 and multiple ideal transmittances TR ideal1 After the processing of step ST36 is executed, the exposure control processing proceeds to step ST38.

[0194] In step ST38, the processor 64 calculates a plurality of actual transmittances TR real1 and multiple ideal transmittances TR ideal1 That is, in step ST38, the difference Δ1 in exposure between the actual transmittance TR real1 and ideal transmittance TR ideal1 After the process of step ST38 is executed, the exposure control process proceeds to step ST40.

[0195] In step ST40, processor 64 performs split exposure EX for each frame 80 included in required number of frames B2. div1 The sensitivity SE, which is one of the exposure factors that define the difference δ1, is adjusted by an adjustment value according to the difference δ1. After the process of step ST40 is executed, the exposure control process proceeds to step ST42.

[0196] Here, if N is a natural number with an initial value of "1", in step ST42, the processor 64 calculates the divided exposure EX for the Nth frame. div1 For example, when the exposure control process proceeds from step ST26 to step ST42, the processor 64 controls the image capturing device 10 to capture an image. div1 Split exposure EX for the Nth frame div1 On the other hand, when the exposure control process proceeds from step ST40 to step ST42, the processor 64 sets the sensitivity SE adjusted in accordance with the difference δ1 calculated for the Nth frame, the shutter speed SP determined for the Nth frame, and the aperture value FV determined for the Nth frame for the imaging device 10, and also sets the current transmittance TR current , multiple real transmittance TR real1 , and target transmittance TR target After setting the transmittance TR for the N-th frame in the electronic ND filter 58, the image capturing device 10 is caused to capture the N-th frame. After the processing of step ST42 is executed, the exposure control processing proceeds to step ST44.

[0197] In step ST44, the processor 64 determines whether the exposure of the Nth frame is the target exposure EX target In step ST44, it is determined whether the exposure of the Nth frame reaches the target exposure EX targetIf the exposure of the Nth frame does not reach the target exposure EX, the determination is negative, and the exposure control process proceeds to step ST46. In step ST46, the processor 64 adds "1" to N. After the process of step ST46 is executed, the exposure control process proceeds to step ST42. In step ST44, the exposure of the Nth frame is set to the target exposure EX. target If the value reaches , the determination is affirmative and the exposure control process ends.

[0198] In step ST48 shown in Figure 26A, the processor 64 determines whether or not the electronic ND filter 58 can track the change in aperture value FV. If the electronic ND filter 58 cannot track the change in aperture value FV in step ST48, the determination is negative, and the exposure control processing proceeds to step ST50 shown in Figure 26D. If the electronic ND filter 58 can track the change in aperture value FV in step ST48, the determination is positive, and the exposure control processing proceeds to step ST72 shown in Figure 26E.

[0199] In step ST50 shown in FIG. 26D, processor 64 calculates the current aperture value FV current , target aperture value FV target , current transmittance TR current , and Target Exposure EX target Based on this, the target sensitivity SE target , and target shutter speed SP target After the process of step ST50 is executed, the exposure control process proceeds to step ST52.

[0200] In step ST52, the processor 64 calculates the current aperture value FV current and target aperture value FV target Based on the aperture drive time T FV After the process of step ST52 is executed, the exposure control process proceeds to step ST54.

[0201] In step ST54, the processor 64 determines the aperture drive time T FVThe required number of frames B3 is calculated based on the frame rate FR. After the process of step ST54 is executed, the exposure control process proceeds to step ST56.

[0202] In step ST56, the processor 64 calculates the number of frames required B3, the current aperture value FV current , and target aperture value FV target Multiple predicted aperture values ​​FV based on pred0 After the process of step ST56 is executed, the exposure control process proceeds to step ST58.

[0203] In step ST58, the processor 64 calculates the current transmittance TR current , current sensitivity SE current , current shutter speed SP current , and multiple predicted aperture values ​​FV pred0 Based on multiple split exposure EX div2 After the process of step ST58 is executed, the exposure control process proceeds to step ST60.

[0204] In step ST60, processor 64 calculates the target exposure EX target and multiple split exposure EX div2 Based on multiple exposure differences EX diff After the process of step ST60 is executed, the exposure control process proceeds to step ST62.

[0205] In step ST62, the processor 64 calculates a plurality of exposure differences EX diff Based on multiple exposure differences EX diff After the process of step ST62 is executed, the exposure control process proceeds to step ST64.

[0206] In step ST64, the processor 64 calculates the current sensitivity SE using the multiple sensitivity adjustment values ​​Δa. current The processor 64 also adjusts the current shutter speed SP using the plurality of shutter speed adjustment values ​​Δb. currentAfter the process of step ST64 is executed, the exposure control process proceeds to step ST66.

[0207] In step ST66, the processor 64 calculates the current transmittance TR current , the adjusted sensitivity SE for the Nth frame, the adjusted shutter speed SP for the Nth frame, and the predicted aperture value FV for the Nth frame. pred0 After the processing of step ST66 is executed, the exposure control processing proceeds to step ST68.

[0208] In step ST68, the processor 64 determines whether the exposure of the Nth frame is the target exposure EX target In step ST68, it is determined whether the exposure of the Nth frame reaches the target exposure EX target If the exposure of the Nth frame does not reach the target exposure EX, the determination is negative, and the exposure control process proceeds to step ST70. In step ST70, the processor 64 adds "1" to N. After the process of step ST70 is executed, the exposure control process proceeds to step ST66. In step ST68, the exposure of the Nth frame is set to the target exposure EX. target If the value reaches , the determination is affirmative and the exposure control process ends.

[0209] In step ST72 shown in FIG. 26E, processor 64 calculates the target exposure EX target , target aperture value FV target , and a target exposure EX based on a plurality of current exposure factors. target Target transmittance TR corresponding to target After the process of step ST72 is executed, the exposure control process proceeds to step ST74.

[0210] In step ST74, the processor 64 calculates the current transmittance TR current After the process of step ST74 is executed, the exposure control process proceeds to step ST76.

[0211] In step ST76, processor 64 calculates the target exposure EXtarget and current transmittance TR current Based on the target exposure EX target Current transmittance TR current The time required for the ideal change to the value T1 is calculated. After the process of step ST76 is executed, the exposure control process proceeds to step ST78.

[0212] In step ST78, the processor 64 calculates the current aperture value FV current and target aperture value FV target Based on the aperture drive time T FV After the process of step ST78 is executed, the exposure control process proceeds to step ST80.

[0213] In step ST80, the processor 64 determines the aperture drive time T FV In step ST80, it is determined whether or not the aperture driving time T FV and the change time T1 do not exceed the threshold value TH2 (i.e., the aperture drive time T FV If the change time T1 is equal to or less than the threshold value TH2, the determination is negative, and the exposure control process proceeds to step ST106 shown in FIG. 26G. FV If both the time T1 and the time T2 of change exceed the threshold value TH2, the determination is affirmative, and the exposure control process proceeds to step ST82 shown in FIG. 26F.

[0214] In step ST82 shown in FIG. 26F, the processor 64 determines the aperture drive time T FV , change time T1, target transmittance TR target , and current transmittance TR current Based on the current transmittance TR current to target transmittance TR target The time required for the change to FV Transmittance during driving time, i.e., transmittance during driving time TR InTime2 After the process of step ST82 is executed, the exposure control process proceeds to step ST84.

[0215] In step ST84, the processor 64 determines the aperture drive time T FV The required number of frames B3 is calculated based on the frame rate FR. After the process of step ST84 is executed, the exposure control process proceeds to step ST86.

[0216] In step ST86, the processor 64 calculates the number of frames required B3, the current aperture value FV current , and target aperture value FV target Multiple predicted aperture values ​​FV based on pred1 After the process of step ST86 is executed, the exposure control process proceeds to step ST88.

[0217] In step ST88, the processor 64 calculates the transmittance within the driving time TR InTime2 , current transmittance TR current , and target transmittance TR target Based on this, the transmittance TR of the electronic ND filter 58 is calculated based on the aperture driving time T FV Current transmittance TR current to target transmittance TR target After the process of step ST88 is executed, the exposure control process proceeds to step ST90.

[0218] In step ST90, the processor 64 calculates the required number of frames B4 based on the change time T3 and the frame rate FR. After the processing of step ST90 is executed, the exposure control processing proceeds to step ST92.

[0219] In step ST92, the processor 64 calculates the number of frames required B4, the target exposure EX target , target aperture value FV target , current aperture value FV current , current transmittance TR current , current sensitivity SE current , current shutter speed SP current , and multiple predicted aperture values ​​FV pred1 Based on multiple predicted transmittance TR pred1 (That is, the predicted transmittance TR for each frame 80 obtained within the required number of frames B4pred1 After the process of step ST92 is executed, the exposure control process proceeds to step ST94.

[0220] In step ST94, the processor 64 sets the larger of the required number of frames B3 and the required number of frames B4 as the maximum number of frames B max1 After the process of step ST94 is executed, the exposure control process proceeds to step ST96.

[0221] In step ST96, the processor 64 determines the maximum number of frames B max1 and Target Exposure EX target Based on multiple split exposure EX div3 After the process of step ST96 is executed, the exposure control process proceeds to step ST98.

[0222] In step ST98, processor 64 generates a plurality of split exposures EX div3 , multiple predicted transmittance TR pred1 , and multiple predicted aperture values ​​FV pred1 Based on multiple predicted sensitivity SE pred1 and predicted shutter speed SP pred1 After the process of step ST98 is executed, the exposure control process proceeds to step ST100.

[0223] In step ST100, the processor 64 calculates the predicted transmittance TR for the Nth frame. pred1 , predicted aperture value FV for the Nth frame pred1 , predicted sensitivity SE for the Nth frame pred1 , predicted shutter speed SP for the Nth frame pred1 After the process of step ST100 is executed, the exposure control process proceeds to step ST102.

[0224] In step ST102, the processor 64 determines whether the exposure of the Nth frame is the target exposure EX target In step ST102, it is determined whether the exposure of the Nth frame reaches the target exposure EX targetIf it has not reached the target exposure EX, the determination is negative and the exposure control process proceeds to step ST104. In step ST104, the processor 64 adds "1" to N. After the process of step ST104 is executed, the exposure control process proceeds to step ST100. In step ST102, the exposure of the Nth frame is set to the target exposure EX. target If the value reaches , the determination is affirmative and the exposure control process ends.

[0225] In step ST106 shown in FIG. 26G, the processor 64 determines the aperture drive time T FV The required number of frames B3 is calculated based on the frame rate FR. After the process of step ST106 is executed, the exposure control process proceeds to step ST108.

[0226] In step ST108, the processor 64 calculates the number of frames required B3, the current aperture value FV current , and target aperture value FV target Multiple predicted aperture values ​​FV based on pred2 After the process of step ST86 is executed, the exposure control process proceeds to step ST110.

[0227] In step ST110, the processor 64 calculates the required number of frames B1 based on the change time T1 and the frame rate FR. After the processing of step ST110 is executed, the exposure control processing proceeds to step ST112.

[0228] In step ST112, the processor 64 calculates the number of frames required B1, the target exposure EX target , target aperture value FV target , current aperture value FV current , current transmittance TR current , current sensitivity SE current , current shutter speed SP current , and multiple predicted aperture values ​​FV pred1 Based on multiple predicted transmittance TR pred2 (That is, the predicted transmittance TR for each frame 80 obtained within the required number of frames B1 pred1After the process of step ST112 is executed, the exposure control process proceeds to step ST114.

[0229] In step ST114, the processor 64 sets the larger of the required number of frames B1 and the required number of frames B3 as the maximum number of frames B. max2 After the process of step ST114 is executed, the exposure control process proceeds to step ST116.

[0230] In step ST116, the processor 64 determines the maximum number of frames B max2 and Target Exposure EX target Based on multiple split exposure EX div4 After the process of step ST116 is executed, the exposure control process proceeds to step ST118.

[0231] In step ST118, processor 64 generates a plurality of split exposures EX div4 , multiple predicted transmittance TR pred2 , and multiple predicted aperture values ​​FV pred2 Based on multiple predicted sensitivity SE pred2 and a plurality of predicted shutter speeds SP pred1 After the process of step ST118 is executed, the exposure control process proceeds to step ST120.

[0232] In step ST120, the processor 64 calculates the predicted transmittance TR for the Nth frame. pred2 , predicted aperture value FV for the Nth frame pred2 , predicted sensitivity SE for the Nth frame pred2 , predicted shutter speed SP for the Nth frame pred2 After the process of step ST120 is executed, the exposure control process proceeds to step ST122.

[0233] In step ST122, the processor 64 determines whether the exposure of the Nth frame is the target exposure EX target In step ST122, it is determined whether the exposure of the Nth frame reaches the target exposure EXtarget If the exposure of the Nth frame does not reach the target exposure EX, the determination is negative, and the exposure control process proceeds to step ST124. In step ST124, the processor 64 adds "1" to N. After the process of step ST124 is executed, the exposure control process proceeds to step ST120. In step ST122, the exposure of the Nth frame is set to the target exposure EX. target If the value reaches , the determination is affirmative and the exposure control process ends.

[0234] As described above, in the imaging device 10 according to the first embodiment, live view image capturing is performed based on the frame rate FR, thereby obtaining a plurality of frames 80. Then, the transmittance TR of the electronic ND filter 58 and the aperture drive time T FV Based on this, the plurality of frames 80 obtained by performing live view image imaging are controlled. Therefore, even while the aperture 40C is being driven, the brightness of the plurality of frames 80 obtained by performing live view image imaging can be kept constant.

[0235] In the imaging device 10 according to the first embodiment, the transmittance TR of the electronic ND filter 58 is set to the current transmittance TR current to target transmittance TR target and the aperture drive time T FV Multiple split exposures EX determined according to the relationship div3 or multiple split exposure EX div4 (i.e., exposure determined for each frame 80 to make the brightness of each frame 80 constant) is applied to each of the exposures of the multiple frames 80 obtained by capturing images for live view images. Therefore, the current transmittance TR current to target transmittance TR target The time required for the aperture to change to is the aperture drive time T FV Whether or not the frame is within the predetermined range, the brightness of the plurality of frames 80 obtained by capturing images for live view images can be kept constant.

[0236] In the imaging device 10 according to the first embodiment, the current transmittance TR current to target transmittance TR target and the aperture drive time T FV When the current transmittance TR exceeds the threshold value TH2, the first control 112 is performed. current to target transmittance TR target The time required for the aperture to change to is the aperture drive time T FV The current transmittance TR current to target transmittance TR target (i.e., change time T3) and aperture drive time T FV and multiple split exposures EX div3 is applied to each of the exposures of the multiple frames 80 obtained by capturing images for live view images. current to target transmittance TR target and the aperture drive time T FV Even if the brightness exceeds the threshold value TH2, the brightness of the plurality of frames 80 obtained by capturing images for live view images can be kept constant.

[0237] In the imaging device 10 according to the first embodiment, the current transmittance TR current to target transmittance TR target (i.e., change time T1) and / or aperture drive time T FV When the current transmittance TR is equal to or less than the threshold value TH2, the second control 114 is performed. current to target transmittance TR target (i.e., change time T1) and aperture drive time T FV and multiple split exposures EX div4 is applied to each of the exposures of the multiple frames 80 obtained by capturing images for live view images. current to target transmittance TR target and / or aperture drive time T FVEven if the brightness of the plurality of frames 80 obtained by capturing images for live view images is equal to or less than the threshold value TH2, the brightness of the plurality of frames 80 can be kept constant.

[0238] Furthermore, in the imaging device 10 according to the first embodiment, a plurality of divided exposures EX div3 The larger of the required number of frames B3 and the required number of frames B4 (i.e., the maximum number of frames B max1 ) is determined based on the number of required frames B3 and the number of required frames B4. div3 Compared to when multiple split exposures EX div3 Since the number of frames required B3 and the number of frames required B4 are averaged, the brightness of the frames 80 can be kept constant. div3 In this case, multiple split exposures EX may be determined based on the smaller of the required number of frames B3 and the required number of frames B4. div3 Compared to when multiple split exposures EX div3 is applied to the exposure of a larger number of frames 80, so that the brightness of a larger number of frames 80 can be kept constant.

[0239] Furthermore, in the imaging device 10 according to the first embodiment, a plurality of divided exposures EX div3 However, multiple predicted transmittance TR pred1 , multiple predicted aperture values ​​FV pred1 , multiple prediction sensitivity SE pred1 , and predicted shutter speed SP pred1 That is, it is determined based on multiple predicted transmittances TR pred1 , multiple predicted aperture values ​​FV pred1 , multiple prediction sensitivity SE pred1 , and predicted shutter speed SP pred1 By performing live view image capture after setting the above, multiple split exposures EX div3Therefore, the brightness of the multiple frames 80 obtained by capturing images for live view images can be kept constant.

[0240] In the imaging device 10 according to the first embodiment, the current transmittance TR current to target transmittance TR target (i.e., change time T1) and aperture drive time T FV In the first control 112 when the current transmittance TR exceeds the threshold value TH2, current and target transmittance TR target Between the time, the transmittance during the driving time TR InTime2 is determined, and multiple predicted transmittances TR pred1 is the current transmittance TR current and transmittance during operation time TR InTime2 In addition, multiple predicted transmittances TR pred1 The transmittance during driving time TR InTime2 Contains multiple predicted transmittances TR pred1 is the current transmittance TR current to target transmittance TR target In this way, the current transmittance TR current to target transmittance TR target During the change process, the transmittance TR InTime2 Multiple predicted transmittances, including TR pred1 Since there is an intervening current to target transmittance TR target Compared to the monotonic change in the current transmittance TR current to target transmittance TR target In addition, multiple predicted transmittance TR pred1 Multiple Split Exposure EX div3 Therefore, the current transmittance TR is used to define the exposure of the plurality of frames 80 obtained by capturing the live view image. current to target transmittance TR target The change time to T FV Multiple split exposures for EX div3 can be applied.

[0241] Furthermore, in the imaging device 10 according to the first embodiment, a plurality of divided exposures EX div4 The larger of the required number of frames B1 and the required number of frames B3 (i.e., the maximum number of frames B max2 ) is determined based on the number of required frames B1 and the number of required frames B3. div4 Compared to when multiple split exposures EX div4 Since the number of frames required B1 and the number of frames required B3 are averaged, the brightness of the frames 80 can be maintained constant. div4 In this case, multiple split exposures EX may be determined based on the smaller of the required number of frames B1 and the required number of frames B3. div4 Compared to when multiple split exposures EX div4 is applied to the exposure of a larger number of frames 80, so that the brightness of a larger number of frames 80 can be kept constant.

[0242] Furthermore, in the imaging device 10 according to the first embodiment, a plurality of divided exposures EX div4 However, multiple predicted transmittance TR pred2 , multiple predicted aperture values ​​FV pred2 , multiple prediction sensitivity SE pred2 , and predicted shutter speed SP pred2 That is, it is determined based on multiple predicted transmittances TR pred2 , multiple predicted aperture values ​​FV pred2 , multiple prediction sensitivity SE pred2 , and predicted shutter speed SP pred2 By performing live view image capture after setting the above, multiple split exposures EX div4 Therefore, the brightness of the multiple frames 80 obtained by capturing images for live view images can be kept constant.

[0243] Furthermore, in the imaging device 10 according to the first embodiment, if the electronic ND filter 58 cannot follow the change in the aperture value FV, the aperture drive time T FV The exposure of the plurality of frames 80 obtained by capturing the live view image within the current and aperture drive time T FV and a plurality of sensitivities SE adjusted with a plurality of sensitivity adjustment values ​​Δa obtained based on the above, a target sensitivity SE target , a plurality of shutter speeds SP adjusted by a plurality of shutter speed adjustment values ​​Δb, a target shutter speed SP target , and multiple predicted aperture values ​​FV pred0 , and current transmittance TR current For example, the aperture drive time T FV Within, the current transmittance TR current , multiple sensitivities SE adjusted by multiple sensitivity adjustment values ​​Δa, target sensitivity SE target , a plurality of shutter speeds SP adjusted by a plurality of shutter speed adjustment values ​​Δb, a target shutter speed SP target , and multiple predicted aperture values ​​FV pred0 The imaging device 10 captures a live view image using the exposure time T FV The exposure of the multiple frames 80 obtained by capturing live view images within the frame is kept constant.

[0244] In the first embodiment, a plurality of divided exposures EX div3 , multiple predicted transmittance TR pred1 , and multiple predicted aperture values ​​FV pred1 Based on multiple predicted sensitivity SE pred1 and a plurality of predicted shutter speeds SP pred1 However, this is merely an example, and multiple predicted sensitivities SE pred1 or multiple predicted shutter speeds SP pred1 For example, multiple split exposures EX div3 , multiple predicted transmittance TR pred1 , multiple predicted aperture values ​​FV pred1 , and current sensitivity SE current A plurality of predicted shutter speeds SP based onpred1 may be calculated, or multiple split exposures EX div3 , multiple predicted transmittance TR pred1 , multiple predicted aperture values ​​FV pred1 , and the current shutter speed SP current Multiple predicted sensitivity based on SE pred1 The same can be said for a plurality of predicted sensitivities SE pred2 and a plurality of predicted shutter speeds SP pred2 The same can be said about...

[0245] [Second embodiment] In the first embodiment described above, if the judgment is positive in step ST48 shown in FIG. 26A (i.e., if the electronic ND filter 58 can track the change in aperture value FV), the processing from step ST72 onwards shown in FIG. 26E is executed regardless of the change in aperture value FV. However, in the second embodiment, an example will be described in which the processor 64 selectively executes the processing of steps ST50 to ST70 shown in FIG. 26D and the processing from step ST72 onwards shown in FIG. 26E, depending on the condition of the change in aperture value FV.

[0246] In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. In addition, in the second embodiment, the differences from the first embodiment will be mainly described.

[0247] In the second embodiment, an example of exposure control processing according to the second embodiment will be described with reference to the flowchart shown in Fig. 27. However, since the flowchart shown in Fig. 27 includes multiple steps that overlap with the flowcharts shown in Fig. 26A to 26G described in the first embodiment, hereinafter, of the multiple steps included in the flowchart shown in Fig. 27, the same steps as those in the flowcharts shown in Fig. 26A to 26G described in the first embodiment will be assigned the same step numbers, and descriptions thereof will be omitted.

[0248] The flowchart shown in FIG. 27 differs from the flowcharts shown in FIGS. 26A to 26G in that step ST200 is provided between step ST48 and step ST72 (see FIG. 26E).

[0249] 27, the processor 64 determines whether the change in the aperture value FV used in the determination in step ST48 exceeds a threshold value TH3. The threshold value TH3 is the value obtained by multiplying the transmittance of the electronic ND filter 58 by the current transmittance TR current Transmittance during driving time TR InTime2 Target transmittance TR target The transmittance of the electronic ND filter 58 can be changed to the current transmittance TR. current Transmittance during driving time TR InTime2 Target transmittance TR target An example of a value determined based on the time when the transmittance of the electronic ND filter 58 cannot be changed to the current transmittance TR current Transmittance during driving time TR InTime2 Target transmittance TR target An example of the threshold value TH3 is the upper limit of the time during which the transmittance of the electronic ND filter 58 cannot be changed to the current transmittance TR current Transmittance during driving time TR InTime2 Target transmittance TR target The upper limit of the time during which the transmittance of the electronic ND filter 58 cannot be changed to the current transmittance TR may be a value determined in advance by testing an actual device and / or computer simulation. current Transmittance during driving time TR InTime2 Target transmittance TR target The upper limit of the time during which the image capture mode cannot be changed is merely an example, and the threshold value TH3 may be a value below the upper limit within an allowable range. The threshold value TH3 may be a fixed value or a variable value that is changed in accordance with a given instruction or various conditions. The threshold value TH3 may be a value determined by the user or a value determined according to the type of image capture mode.

[0250] In step ST200, if the change in the aperture value FV used in the determination in step ST48 exceeds the threshold value TH3, the determination is affirmative, and the processor 64 executes the processes of step ST72 and subsequent steps shown in FIG. 26E. In step ST200, if the change in the aperture value FV used in the determination in step ST48 does not exceed the threshold value TH3 (i.e., if the change in the aperture value FV used in the determination in step ST48 is equal to or less than the threshold value TH3), the determination is negative, and the processor 200 executes the processes of steps ST50 to ST70 shown in FIG. 26D. In the second embodiment, the threshold value TH3 is an example of a "first predetermined change amount" according to the present disclosure.

[0251] If the change in the aperture value FV used in the determination in step ST48 exceeds the threshold value TH3, the transmittance of the electronic ND filter 58 is set to the current transmittance TR current Transmittance during driving time TR InTime2 Target transmittance TR target In this case, the processor 64 executes the processes from step ST72 onward shown in FIG.

[0252] On the other hand, if the change in the aperture value FV used in the determination in step ST48 does not exceed the threshold value TH3 (that is, if the change in the aperture value FV used in the determination in step ST48 is equal to or less than the threshold value TH3), the transmittance of the electronic ND filter 58 is set to the current transmittance TR current Transmittance during driving time TR InTime2 Target transmittance TR target It is impossible to change the transmittance during the driving time (i.e., InTime2 In this case, the processing of steps ST50 to ST70 shown in FIG. 26D is performed. This is because the processing of steps ST50 to ST70 shown in FIG. 26D requires the setting of the transmittance within the driving time TR InTime2 This is because it does not include any processing to set or use the

[0253] By doing so, even if the change in the aperture value FV used in the determination of step ST48 exceeds the threshold value TH3, the aperture drive time T FV By capturing live view images within the frame 80, the exposure of the multiple frames 80 can be kept constant.

[0254] [Third embodiment] In the first embodiment, while the exposure of the multiple frames 80 obtained by capturing live view images is being controlled (i.e., while the exposure control process is being performed), the amount of change in the aperture value FV (i.e., the current aperture value FV current to target aperture FV target In the above, an example was given in which it was assumed that the amount of change in the aperture value FV (the amount of change up to the aperture value FV) was not changed. However, in the third embodiment, an example will be described in which the amount of change in the aperture value FV is changed while the exposure of multiple frames 80 obtained by capturing images for live view images is being controlled.

[0255] In the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. In the third embodiment, the differences from the first embodiment will be mainly described.

[0256] In this third embodiment, an example of exposure control processing according to this third embodiment will be described with reference to the flowcharts shown in Figures 28A to 28F. However, since the flowcharts shown in Figures 28A to 28F include multiple steps that overlap with the flowcharts shown in Figures 26A to 26G described in the first embodiment, hereinafter, of the multiple steps included in the flowcharts shown in Figures 28A to 28F, the same steps as those in the flowcharts shown in Figures 26A to 26G described in the first embodiment will be assigned the same step numbers, and descriptions thereof will be omitted.

[0257] The flowcharts shown in Figures 28A to 28F differ from the flowcharts shown in Figures 26A to 26G in that they have steps ST300 to ST310 (see Figures 28A and 28B) instead of steps ST102 and ST104, steps ST312 to ST322 (see Figures 28C and 28D) instead of steps ST122 and ST124, and steps ST324 to ST334 (see Figures 28E and 28F) instead of steps ST68 and ST70.

[0258] In step ST300 shown in FIG. 28A, the processor 64 determines whether the exposure of the Nth frame is the target exposure EX target In step ST200, it is determined whether the exposure of the Nth frame reaches the target exposure EX. target If the exposure of the Nth frame does not reach the target exposure EX, the determination is negative, and the exposure control process proceeds to step ST302 shown in Fig. 28B. target If the value reaches , the determination is affirmative and the exposure control process ends.

[0259] In step ST302 shown in FIG. 28B, the processor 64 calculates the target aperture value FV target In the third embodiment, the change amount of the aperture value FV is determined by the user's instruction to update the current aperture value FV. current to target aperture FV target In the third embodiment, for the sake of convenience, the target aperture value FV target The currently set target aperture value FV target a new value different from the target aperture FV target ) is specified by the user to change the amount of change in the aperture value FV.

[0260] The threshold value TH4 is a value based on the amount of change in the aperture value FV that prevents the user from visually noticing a change in brightness between frames 80 due to a change in the aperture value FV. An example of a value based on the amount of change in the aperture value FV that prevents the user from visually noticing a change in brightness between frames 80 due to a change in the aperture value FV is an upper limit of the amount of change in the aperture value FV that prevents the user from visually noticing a change in brightness between frames 80 due to a change in the aperture value FV. An example of the threshold value TH4 is a value determined in advance through testing using an actual device and / or computer simulation as an upper limit of the amount of change in the aperture value FV that prevents the user from visually noticing a change in brightness between frames 80 due to a change in the aperture value FV. The upper limit of the amount of change in the aperture value FV that prevents the user from visually noticing a change in brightness between frames 80 due to a change in the aperture value FV is merely an example and may be a value below the upper limit within an allowable range. Furthermore, the threshold value TH4 may be a fixed value or a variable value that is changed in accordance with given instructions or various conditions. The threshold value TH4 may be a value determined by the user, or may be a value determined according to the type of imaging mode.

[0261] In step ST302, if the amount of change in aperture value FV due to an instruction given by the user does not exceed threshold value TH4, the determination is negative and "1" is added to N. Then, the exposure control process proceeds to step ST100 shown in Fig. 28A. In step ST302, if the amount of change in aperture value FV due to an instruction given by the user exceeds threshold value TH4, the determination is positive and the exposure control process proceeds to step ST304.

[0262] In steps ST304 to ST308, the processor 64 executes the same processes as steps ST10 to ST14 shown in Fig. 26A. After the process of step ST308 is executed, the exposure control process proceeds to step ST310.

[0263] In step ST310, the processor 64 calculates a new target aperture value FV target (i.e., updated target aperture FV target ) and the predicted aperture value FV for the Nth frame pred1 The difference between the target aperture value FV and the target aperture value FV is acquired as the change in the aperture value FV. Here, a difference is used as an example, but it may be a ratio. target and predicted aperture value FV for the Nth frame pred1 It is sufficient if it is an index showing the degree of difference between the aperture value FV designated by the user and the predicted aperture value FV for the Nth frame. pred1 The difference between this and is an example of the "degree of difference between the aperture value before updating and the aperture value after updating" according to the present disclosure. After the processing of step ST310 is executed, the exposure control processing proceeds to step ST48. From step ST48 onwards, the change in aperture value FV acquired in step ST310 is used in the same manner as the change in aperture value FV described in the first embodiment above. For example, in step ST48, it is determined whether the change in aperture value FV acquired in step ST310 can be tracked by the electronic ND filter 58.

[0264] If the change in aperture value FV acquired in step ST310 cannot be tracked by the electronic ND filter 58, the processes of steps ST50 to ST70 shown in FIG. 26D are executed by the processor 64. Therefore, as in the first embodiment, the aperture drive time T FV The exposure of the multiple frames 80 obtained by capturing live view images within the frame is kept constant. Also, if the change in aperture value FV acquired in step ST310 can be tracked by the electronic ND filter 58, the processes from step ST72 onward shown in FIG. 26E are executed by the processor 64, so the maximum number of frames B is maintained, as in the first embodiment. max1 For each exposure of the frame 80 obtained in the split exposure EX div1 is applied, or the maximum number of frames B max2 For each exposure of the frame 80 obtained in the split exposure EX div2is applied, which keeps the exposure of the multiple frames 80 constant.

[0265] In step ST312 shown in FIG. 28C, the processor 64 determines whether the exposure of the Nth frame is the target exposure EX target In step ST312, it is determined whether the exposure of the Nth frame reaches the target exposure EX target If the exposure of the Nth frame does not reach the target exposure EX, the determination is negative, and the exposure control process proceeds to step ST314 shown in Fig. 28D. target If the value reaches , the determination is affirmative and the exposure control process ends.

[0266] In step ST314 shown in FIG. 28D, processor 64 calculates a target aperture value FV target In step ST314, if the amount of change in aperture value FV due to the instruction from the user to update FV has not exceeded threshold value TH4, the determination is negative and "1" is added to N. Then, the exposure control process proceeds to step ST120 shown in FIG. 28C.

[0267] In step ST314, if the amount of change in aperture value FV due to an instruction given by the user exceeds threshold value TH4, the determination is affirmative and the exposure control process proceeds to step ST316.

[0268] In steps ST316 to ST320, the processor 64 executes the same processes as steps ST10 to ST14 shown in Fig. 26A. After the process of step ST320 is executed, the exposure control process proceeds to step ST322.

[0269] In step ST322, the processor 64 calculates the new target aperture value FV target (i.e., updated target aperture FV target ) and the predicted aperture value FV for the Nth frame pred2The difference between the target aperture value FV and the target aperture value FV is acquired as the change in the aperture value FV. Here, a difference is used as an example, but it may be a ratio. target and predicted aperture value FV for the Nth frame pred2 It is sufficient if it is an index showing the degree of difference between the aperture value FV designated by the user and the predicted aperture value FV for the Nth frame. pred2 The difference between this and is an example of the "degree of difference between the aperture value before updating and the aperture value after updating" according to the present disclosure. After the processing of step ST322 is executed, the exposure control processing proceeds to step ST48 (see FIG. 28B). From step ST48 onwards, the change in aperture value FV acquired in step ST322 is used in the same manner as the change in aperture value FV described in the first embodiment above. For example, in step ST48, it is determined whether the change in aperture value FV acquired in step ST322 can be tracked by the electronic ND filter 58.

[0270] If the change in aperture value FV acquired in step ST322 cannot be tracked by the electronic ND filter 58, the processes of steps ST50 to ST70 shown in FIG. 26D are executed by the processor 64. Therefore, as in the first embodiment, the aperture drive time T FV The exposure of the multiple frames 80 obtained by capturing live view images within the frame is kept constant. Also, if the change in aperture value FV acquired in step ST322 can be tracked by the electronic ND filter 58, the processes from step ST72 onward shown in FIG. 26E are executed by the processor 64, so the maximum number of frames B is maintained, as in the first embodiment. max1 For each exposure of the frame 80 obtained in the split exposure EX div1 is applied, or the maximum number of frames B max2 For each exposure of the frame 80 obtained in the split exposure EX div2 is applied, which keeps the exposure of the multiple frames 80 constant.

[0271] In step ST324 shown in FIG. 28E, the processor 64 determines whether the exposure of the Nth frame is the target exposure EX targetIn step ST324, it is determined whether the exposure of the Nth frame reaches the target exposure EX target If the exposure of the Nth frame does not reach the target exposure EX, the determination is negative, and the exposure control process proceeds to step ST326 shown in FIG. target If the value reaches , the determination is affirmative and the exposure control process ends.

[0272] In step ST326 shown in FIG. 28F, processor 64 calculates a target aperture value FV target In step ST326, if the amount of change in aperture value FV due to the instruction from the user to update FV has not exceeded threshold value TH4, the determination is negative and "1" is added to N. Then, the exposure control process proceeds to step ST66 shown in FIG. 28E.

[0273] In step ST326, if the amount of change in aperture value FV due to an instruction given by the user exceeds threshold value TH4, the determination is affirmative and the exposure control process proceeds to step ST328.

[0274] In steps ST328 to ST332, the processor 64 executes the same processes as steps ST10 to ST14 shown in Fig. 26A. After the process of step ST332 is executed, the exposure control process proceeds to step ST334.

[0275] In step ST334, the processor 64 calculates the new target aperture value FV target (i.e., updated target aperture FV target ) and the predicted aperture value FV for the Nth frame pred0 The difference between the target aperture value FV and the target aperture value FV is acquired as the change in the aperture value FV. Here, a difference is used as an example, but it may be a ratio. target and predicted aperture value FV for the Nth frame pred0It is sufficient if it is an index showing the degree of difference between the aperture value FV designated by the user and the predicted aperture value FV for the Nth frame. pred0 The difference between this and the aperture value FV is an example of the "degree of difference between the aperture value before updating and the aperture value after updating" according to the present disclosure. After the processing of step ST334 is executed, the exposure control processing proceeds to step ST48 (see FIG. 28B). From step ST48 onwards, the change in aperture value FV acquired in step ST334 is used in the same manner as the change in aperture value FV described in the first embodiment above. For example, in step ST48, it is determined whether the change in aperture value FV acquired in step ST334 can be tracked by the electronic ND filter 58.

[0276] If the change in aperture value FV acquired in step ST334 cannot be tracked by the electronic ND filter 58, the processes of steps ST50 to ST70 shown in FIG. 26D are executed by the processor 64. Therefore, as in the first embodiment, the aperture driving time T FV The exposure of the multiple frames 80 obtained by capturing live view images within the frame is kept constant. Also, if the change in aperture value FV acquired in step ST334 can be tracked by the electronic ND filter 58, the processes from step ST72 onward shown in FIG. 26E are executed by the processor 64, so the maximum number of frames B is maintained, as in the first embodiment. max1 For each exposure of the frame 80 obtained in the split exposure EX div1 is applied, or the maximum number of frames B max2 For each exposure of the frame 80 obtained in the split exposure EX div2 is applied, which keeps the exposure of the multiple frames 80 constant.

[0277] As described above, in the exposure control process according to the third embodiment, the change in aperture value FV is acquired in step ST310, step ST322, or step ST334. Then, in step ST48, the trackability of the transmittance TR of the electronic ND filter 58 with respect to the change in aperture value FV is determined. Then, the exposure of the multiple frames 80 obtained by capturing images for live view images is updated using a method according to the trackability determined (for example, the processes of steps ST50 to ST70 shown in FIG. 26D or the processes from step ST72 onwards shown in FIG. 26E). As a result, even if the change in aperture value FV exceeds threshold value TH4 due to the user issuing an instruction to update the target aperture value FVtarget while the exposure control process is being performed, the exposure of the multiple frames 80 is kept constant.

[0278] [Fourth embodiment] In the first embodiment, the target transmittance TR target and transmittance during operation time TR InTime2 Multiple split exposures EX div3 However, an example of the embodiment in which the target transmittance TR is applied as an exposure of a plurality of frames 80 obtained by capturing an image for a live view image has been given. target and transmittance during operation time TR InTime2 The larger the difference between the target transmittance TR and the target transmittance TR, the larger the fluctuation range of the exposure factor, and therefore, problems associated with an increase in the fluctuation range of the exposure factor are more likely to occur. target and transmittance during operation time TR InTime2 The larger the difference between the multiple predicted transmittances TR pred1 This increases the range of variation between multiple predicted transmittances TR pred1The fluctuation range of other exposure factors that compensate for the fluctuations between the two also becomes larger. For example, the greater the fluctuation range of the sensitivity SE, the greater the possibility of noise occurring due to fluctuations in the sensitivity SE. Furthermore, the greater the fluctuation range of the shutter speed SP, the greater the physical load placed on the shutter, which may be a factor in shortening the life of the shutter. Furthermore, the greater the fluctuation range of the transmittance TR of the electronic ND filter 58, the greater the voltage applied to the electronic ND filter 58, which may also be a factor in shortening the life of the electronic ND filter 58. Therefore, in the fourth embodiment, the target transmittance TR target and transmittance during operation time TR InTime2 An example of the control is performed to suppress the fluctuation range of the exposure factor depending on the degree of difference between the two.

[0279] In the fourth embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. In the fourth embodiment, the differences from the first embodiment will be mainly described.

[0280] In the present fourth embodiment, an example of exposure control processing according to the present fourth embodiment will be described with reference to the flowcharts shown in Figures 29A to 29C. However, since the flowcharts shown in Figures 29A to 29C include multiple steps that overlap with the flowcharts shown in Figures 26A to 26G described in the first embodiment, hereinafter, of the multiple steps included in the flowcharts shown in Figures 29A to 29C, the same steps as those in the flowcharts shown in Figures 26A to 26G described in the first embodiment will be assigned the same step numbers, and descriptions thereof will be omitted.

[0281] The flowcharts shown in FIGS. 29A to 29C differ from the flowcharts shown in FIGS. 26A to 26G in that steps ST400 to ST410 are provided between step ST82 and step ST84, and steps ST412 to ST432 are provided.

[0282] In step ST400, processor 64 calculates a target transmittance TR target and transmittance during operation time TR InTime2Here, a difference δ2 is calculated as an absolute value of the difference in exposure between the target transmittance TR target and transmittance during operation time TR InTime2 The absolute value of the difference in exposure between the target transmittance TR target and transmittance during operation time TR InTime2 After the process of step ST400 is executed, the exposure control process proceeds to step ST402.

[0283] Here, the difference δ2 is shown as an example, but the target transmittance TR target and transmittance during operation time TR InTime2 The target transmittance TR may be a ratio of one of the two to the other. target and transmittance during operation time TR InTime2 Any indicator showing the degree of difference from the original image may be used.

[0284] In step ST402, the processor 64 determines whether the difference δ2 exceeds a threshold TH5. In the fourth embodiment, the difference δ2 is an example of a "first dissimilarity" according to the present disclosure, and the threshold TH6 is an example of a "predetermined dissimilarity" according to the present disclosure.

[0285] The threshold value TH5 is a value determined based on the difference δ2 at which no defects occur due to variations in the exposure factor (e.g., sensitivity SE, shutter speed SP, and / or transmittance TR). An example of a value determined based on the difference δ2 at which no defects occur due to variations in the exposure factor is the upper limit of the difference δ2 at which no defects occur due to variations in the exposure factor. An example of the threshold value TH5 is a value determined in advance through tests using an actual device and / or computer simulation as the upper limit of the difference δ2 at which no defects occur due to variations in the exposure factor. The upper limit of the difference δ2 at which no defects occur due to variations in the exposure factor is merely an example, and may be a value below the upper limit within an allowable range. Furthermore, the threshold value TH5 may be a fixed value or a variable value that is changed in accordance with given instructions or various conditions. The threshold value TH5 may be a value determined by the user or a value determined according to the type of imaging mode.

[0286] In step ST402, if the difference δ2 does not exceed the threshold value TH5, the determination is negative and the exposure control process proceeds to step ST410. In step ST402, if the difference δ2 exceeds the threshold value TH5, the determination is positive and the exposure control process proceeds to step ST404.

[0287] In step ST404, the processor 64 calculates the current transmittance TR current Transmittance during driving time TR InTime2 After the process of step ST404 is executed, the exposure control process proceeds to step ST406.

[0288] In step ST406, the processor 64 determines whether the change time T4 is less than the threshold value TH6. In the fourth embodiment, the change time T4 is an example of the "transmittance change time" according to the present disclosure, and the threshold value TH6 is an example of the "eighth threshold value" and "tenth threshold value" according to the present disclosure.

[0289] The threshold TH6 is the current transmittance TR current The transmittance TR is calculated by the time it changes from exposure to light. InTime1 This is a value determined based on the change time T4 that does not cause problems due to fluctuations in exposure factors (e.g., sensitivity SE, shutter speed SP, and / or transmittance TR) in order to change the exposure to the value realized by the current transmittance TR. current The transmittance TR is calculated by the time it changes from exposure to light. InTime An example of a value determined based on the change time T4 that does not cause problems due to fluctuations in the exposure factor in order to change to the exposure realized by the current transmittance TR current The transmittance TR is calculated by the time it changes from exposure to light. InTime1 An example of the threshold value TH6 is the lower limit of the change time T4 that does not cause problems due to fluctuations in the exposure factor in order to change the exposure to the exposure realized by the current transmittance TR current The transmittance TR is calculated by the time it changes from exposure to light. InTime1The lower limit of the change time T4 that does not cause problems due to fluctuations in the exposure factor in order to change the exposure to the value realized by the current transmittance TR is a value determined in advance by tests using an actual device and / or computer simulations. current The transmittance TR is calculated by the time it changes from exposure to light. InTime1 The lower limit of the change time T4 that does not cause problems due to variations in the exposure factor to change the exposure to the exposure realized by is merely an example, and the change time T4 may be a value above the lower limit within an acceptable range. Furthermore, the threshold value TH6 may be a fixed value or a variable value that is changed in accordance with given instructions or various conditions. The threshold value TH6 may be a value determined by the user or a value determined according to the type of imaging mode.

[0290] In step ST406, if the change time T4 is not less than the threshold value TH6, the determination is negative and the exposure control process proceeds to step ST410. In step ST406, if the change time T4 is less than the threshold value TH6, the determination is positive and the exposure control process proceeds to step ST408.

[0291] In step ST408, the processor 64 calculates a plurality of intermediate transmittances TR mid (See Figure 30) to calculate multiple predicted transmittances TR pred1 Multiple predicted transmittance TR pred3 (See Figure 30.) pred3 is the current transmittance TR current to target transmittance TR target The time it takes to change to (i.e., the change time T3) is the aperture drive time T FV and the current transmittance TR current From multiple intermediate transmittance TR mid Target transmittance TR target The multiple transmittances TR are defined as the process by which the transmittance changes from pred3 There are several intermediate transmittance TR mid (In the example shown in FIG. 30, two intermediate transmittances TR mid ) are included.mid The transmittance TR of the electronic ND filter 58 is currently TR current From multiple intermediate transmittance TR mid Target transmittance TR target The time required for the change to the target transmittance TR is equal to or less than the threshold value TH1. target The maximum value of difference δ3, which is the absolute value of the difference in exposure between the transmittances TR and δ2, is smaller than the maximum value of difference δ2.

[0292] Here, the intermediate transmittance TR mid and target transmittance TR target The absolute value of the difference in exposure between the intermediate transmittance TR mid and target transmittance TR target The intermediate transmittance TR may be the absolute value of the difference between the mid and target transmittance TR target Instead of the absolute value of the difference in exposure between mid and target transmittance TR target may be used, and the intermediate transmittance TR mid and target transmittance TR target Any indicator showing the degree of difference from the original image may be used.

[0293] In the fourth embodiment, a plurality of predicted transmittances TR obtained by executing the process of step ST408 are pred3 (See FIG. 30) are examples of "plurality of second actual transmittances" and "plurality of third actual transmittances" according to the present disclosure. Also, the maximum value of the difference δ3 is an example of "maximum difference between the plurality of intermediate transmittances and the second transmittance" according to the present disclosure.

[0294] After the process of step ST408 is executed, the exposure control process proceeds to step ST410.

[0295] In step ST410, processor 64 calculates the intermediate transmittance TR in step ST408. mid In step ST410, it is determined whether the intermediate transmittance TR midIf the intermediate transmittance TR has not been calculated, the determination is negative, and the exposure control process proceeds to step ST84 shown in FIG. 29B, and the processes of steps ST84 to ST104 are executed by the processor 64 (see FIG. 29B). mid is calculated, the determination is affirmative, and the exposure control process proceeds to step ST412 shown in FIG. 29C.

[0296] In steps ST412 and ST414 shown in Figure 29C, the same processes as steps ST84 and ST86 (see Figure 29B) are executed by the processor 64. After the process of step ST414 is executed, the exposure control process proceeds to step ST416.

[0297] In step ST416, the processor 64 sets the transmittance TR of the electronic ND filter 58 to the current transmittance TR current , multiple predicted transmittance TR pred3 , and target transmittance TR target The time required for the change to occur is calculated as T5. The time required for the change to occur is calculated as T5. current , multiple predicted transmittance TR pred3 , and target transmittance TR target is calculated using an arithmetic expression with the independent variable being the time T5 of change as the dependent variable. After the process of step ST416 is executed, the exposure control process proceeds to step ST418.

[0298] In step ST418, the processor 64 calculates the number of frames corresponding to the change time T5, i.e., the required number of frames B5, which is the number of frames required for the change time T5 to pass, based on the change time T5 and the frame rate FR. For example, the required number of frames B5 is calculated by "(change time T5) x (frame rate FR)". After the processing of step ST418 is executed, the exposure control processing proceeds to step ST420.

[0299] In the fourth embodiment, the required number of frames B5 is an example of the "fifth number of frames" according to the present disclosure.

[0300] In step ST420, processor 64 calculates the number of frames required B5, the target exposure EX target , target aperture value FV target , current aperture value FV current , current transmittance TR current , current sensitivity SE current , current shutter speed SP current , and multiple predicted aperture values ​​FV pred3 Based on multiple predicted transmittance TR pred3 (That is, the predicted transmittance TR for each frame 80 obtained within the required number of frames B5 pred3 After the process of step ST420 is executed, the exposure control process proceeds to step ST422.

[0301] In step ST422, the processor 64 sets the larger of the required number of frames B3 and the required number of frames B5 as the maximum number of frames B. max3 After the process of step ST422 is executed, the exposure control process proceeds to step ST424.

[0302] In step ST424, the processor 64 determines the maximum number of frames B max3 and Target Exposure EX target Based on multiple split exposure EX div5 Here, in order to maintain a constant brightness of the multiple frames 80 obtained by capturing images for live view images, multiple split exposures EX div5 That is, the processor 64 calculates the target exposure EX target The same exposure as the maximum number of frames B max3 Split exposure EX for each of the 80 frames div5 In this way, multiple split exposures EX div5 is the maximum number of frames B max3 and Target Exposure EX target It is determined based on the following.

[0303] Here, the maximum number of frames B max3 The maximum number of frames is B max3 Alternatively, the average value of the required number of frames B3 and the required number of frames B5 may be used.

[0304] In the next step ST426, the processor 64 generates a plurality of split exposures EX div5 , multiple predicted transmittance TR pred3 , and multiple predicted aperture values ​​FV pred1 Based on multiple predicted sensitivity SE pred3 and a plurality of predicted shutter speeds SP pred3 Calculate.

[0305] Split exposure EX div5 is defined by multiple exposure factors. Split exposure EX div5 The multiple exposure factors that define the predicted transmittance TR pred3 , predicted aperture value FV pred1 , prediction sensitivity SE pred1 , and predicted shutter speed SP pred3 Refers to...

[0306] Multiple Split Exposure EX div5 , multiple predicted transmittance TR pred3 , and multiple predicted aperture values ​​FV pred1 Multiple predicted sensitivities SE calculated based on pred3 Each of these is the current aperture value FV current to target aperture FV target This is a predicted value of the sensitivity SE used for each frame 80 obtained up to the point where multiple split exposures EX div5 , multiple predicted transmittance TR pred3 , and multiple predicted aperture values ​​FV pred1 A plurality of predicted shutter speeds SP calculated based on pred3 is the current aperture value FV current to target aperture FV target This is a predicted value of the shutter speed SP to be used for each frame 80 obtained up to the point where the shutter speed SP is reached.

[0307] Multiple prediction sensitivity SE pred3 and a plurality of predicted shutter speeds SP pred3The calculation of EX is done for multiple split exposures. div5 , multiple predicted transmittance TR pred3 , and multiple predicted aperture values ​​FV pred1 are used as independent variables, and multiple prediction sensitivity SE pred3 and a plurality of predicted shutter speeds SP pred3 is an arithmetic expression with as the dependent variable.

[0308] In this way, multiple prediction sensitivities SE pred3 and a plurality of predicted shutter speeds SP pred3 Multiple Split Exposure EX div5 It is calculated based on multiple predicted sensitivities SE pred3 and a plurality of predicted shutter speeds SP pred3 Multiple split exposures EX used to calculate div5 is the target exposure EX target Therefore, multiple predicted sensitivities SE pred3 and a plurality of predicted shutter speeds SP pred3 is the target exposure EX target It can also be said that this is an exposure factor that is set in the imaging device 10 in accordance with the image.

[0309] In the next step ST428, the processor 64 calculates the predicted transmittance TR for the Nth frame. pred3 , predicted aperture value FV for the Nth frame pred1 , predicted sensitivity SE for the Nth frame pred3 , predicted shutter speed SP for the Nth frame pred3 After the process of step ST428 is executed, the exposure control process proceeds to step ST430.

[0310] In step ST430, the processor 64 determines whether the exposure of the Nth frame is the target exposure EX target In step ST430, it is determined whether the exposure of the Nth frame reaches the target exposure EX. targetIf the exposure of the Nth frame does not reach the target exposure EX, the determination is negative, and the exposure control process proceeds to step ST432. In step ST432, the processor 64 adds "1" to N. After the process of step ST432 is executed, the exposure control process proceeds to step ST428. In step ST430, the exposure of the Nth frame is set to the target exposure EX. target If the value reaches , the determination is affirmative and the exposure control process ends.

[0311] As described above, in the imaging device 10 according to the fourth embodiment, the transmittance within the driving time TR InTime2 Multiple predicted transmittances, including TR pred1 Multiple predicted transmittances TR with smaller fluctuation range than pred3 (i.e., the multiple intermediate transmittances TR shown in FIG. 30 mid Multiple predicted transmittances, including TR pred3 ) based on multiple split exposures EX div5 is calculated. Multiple split exposures EX div5 The range of variation of multiple exposure factors that define the div3 Therefore, it is possible to suppress problems that arise due to fluctuations in multiple exposure factors (for example, an increase in noise caused by a large fluctuation range in sensitivity SE, or an increase in physical load on the shutter caused by a large fluctuation range in shutter speed).

[0312] In the fourth embodiment, a plurality of divided exposures EX div5 , multiple predicted transmittance TR pred3 , and multiple predicted aperture values ​​FV pred1 Based on multiple predicted sensitivity SE pred3 and a plurality of predicted shutter speeds SP pred3 However, this is merely an example, and multiple predicted sensitivities SE pred3 or multiple predicted shutter speeds SP pred3 For example, multiple split exposures EX div5 , multiple predicted transmittance TR pred3 , multiple predicted aperture values ​​FV pred1 , and current sensitivity SE currentA plurality of predicted shutter speeds SP based on pred3 may be calculated, or multiple split exposures EX div5 , multiple predicted transmittance TR pred3 , multiple predicted aperture values ​​FV pred1 , and the current shutter speed SP current Multiple predicted sensitivity based on SE pred3 may be calculated.

[0313] [Variations] In each of the above embodiments, the aperture driving time T FV In the above embodiment, it is determined whether or not both the aperture driving time T and the change time T1 have exceeded the threshold value TH2, but this is merely an example. For example, as shown in FIG. 31, the process of step ST80 may be replaced by the process of step ST80A. In step ST80A, the aperture driving time T FV and the change time T1 exceeds a threshold value TH7. An example of the threshold value TH7 is the current transmittance TR current to target transmittance TR target and the aperture drive time T FV The threshold value TH7 may be a fixed value or a variable value that is changed according to a given instruction or various conditions.

[0314] In step ST80A, the aperture driving time T FV If the difference between the aperture driving time T and the change time T1 exceeds the threshold value TH7, the determination is affirmative, and the exposure control process proceeds to step ST82 shown in FIG. FV If the difference between the aperture driving time T and the change time T1 does not exceed the threshold value TH7, the determination is negative, and the exposure control process proceeds to step ST106 shown in FIG. FV The difference between the change time T1 and the change time T2 is an example of the "degree of difference between the change time and the drive time," and the threshold value TH7 is an example of the "second threshold value," "fourth threshold value," "sixth threshold value," and "ninth threshold value" according to the present disclosure.

[0315] Also, here, the aperture drive time T FV The difference between the change time T1 and the aperture drive time T FV and the ratio of the change time T1 to the other, and the aperture drive time T FV It is sufficient if it is an index showing the degree of difference between the change time T1 and the change time T2.

[0316] In the above embodiments, the time required for the transmittance TR of the electronic ND filter 58 to change, i.e., the change time (for example, change times T1, T2, T3, T4, and T5), has been exemplified, but the number of frames may also be used as the change time. In other words, the concept of change time may include the number of frames.

[0317] In the above embodiments, various maximum values ​​(such as the maximum value of the difference δ1 and the maximum value of the difference δ3) have been exemplified, but all of the above maximum values ​​mean maximum values ​​within a predetermined range.

[0318] In the above embodiments, monotonic changes have been exemplified, but monotonic changes refer to, for example, linear changes or exponential changes, etc. Furthermore, examples of monotonic changes include monotonic increases and decreases.

[0319] In each of the above embodiments, an example of exposure control processing when capturing images for live view images has been given, but the present disclosure is not limited to this, and the above-described exposure control processing can be applied when continuous image capturing is performed, such as when capturing images for recording moving images, when continuous image capturing is performed with a fixed image capturing interval, or when continuous image capturing is performed with a variable image capturing interval.

[0320] In the above embodiment, an example has been described in which the exposure control processing program PG is stored in the storage 66, but the present disclosure is not limited to this. For example, the exposure control processing program PG may be stored in a portable, computer-readable, non-transitory storage medium such as an SSD or a USB memory. The exposure control processing program PG stored in the non-transitory storage medium is installed in the system controller 12 of the imaging device 10. The processor 64 executes exposure control processing in accordance with the exposure control processing program PG.

[0321] Alternatively, the exposure control processing program PG may be stored in a storage device such as another computer or server device connected to the imaging device 10 via a network, and the exposure control processing program PG may be downloaded in response to a request from the imaging device 10 and installed in the system controller 12.

[0322] It is not necessary to store the entire exposure control processing program PG in a storage device such as another computer or server device connected to the imaging device 10, or in the storage 66; only a part of the exposure control processing program PG may be stored therein.

[0323] Furthermore, although the imaging device 10 shown in FIGS. 1 and 2 has a built-in system controller 12, the present disclosure is not limited to this. For example, the system controller 12 may be provided outside the imaging device 10.

[0324] In the above embodiment, the system controller 12 is exemplified, but the present disclosure is not limited to this, and a device including an ASIC, an FPGA, and / or a PLD may be applied instead of the system controller 12. Furthermore, instead of the system controller 12, a combination of a hardware configuration and a software configuration may be used.

[0325] The hardware resources for executing the exposure control process described in the above embodiments can be various processors, as listed below. Examples of processors include a CPU, which is a general-purpose processor that functions as a hardware resource for executing exposure control processes by executing software, i.e., a program. Examples of processors include dedicated electrical circuits, such as FPGAs, PLDs, or ASICs, which are processors with circuit configurations designed specifically for executing specific processes. Each processor has built-in or connected memory, and each processor uses the memory to execute the exposure control process.

[0326] The hardware resource that executes the exposure control process may be configured with one of these various processors, or may be configured with a combination of two or more processors of the same or different types (for example, a combination of multiple FPGAs, or a combination of a CPU and an FPGA). Also, the hardware resource that executes the exposure control process may be a single processor.

[0327] As an example of a system configured with a single processor, first, one processor is configured by combining one or more CPUs and software, and this processor functions as a hardware resource that executes exposure control processing. Second, there is a system that uses a processor that realizes the functions of the entire system, including multiple hardware resources that execute exposure control processing, on a single IC chip, as typified by SoCs. In this way, the exposure control processing is realized using one or more of the above-mentioned various processors as hardware resources.

[0328] Furthermore, the hardware structure of these various processors can be, more specifically, an electric circuit that combines circuit elements such as semiconductor devices. The above exposure control process is merely an example. Therefore, it goes without saying that unnecessary steps may be deleted, new steps may be added, or the processing order may be rearranged, without departing from the spirit of the process.

[0329] The above-described description and illustrations are a detailed explanation of the parts related to the present disclosure and are merely an example of the present disclosure. For example, the above description of the configuration, functions, actions, and effects is an explanation of an example of the configuration, functions, actions, and effects of the parts related to the present disclosure. Therefore, it goes without saying that unnecessary parts may be deleted, new elements may be added, or elements may be replaced with other parts from the above-described description and illustrations, as long as they do not deviate from the gist of the present disclosure. Furthermore, in order to avoid confusion and facilitate understanding of the parts related to the present disclosure, the above-described description and illustrations omit explanations of common general technical knowledge that do not require particular explanation to enable the implementation of the present disclosure.

[0330] All publications, patent applications, and technical standards mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent application, or technical standard was specifically and individually indicated to be incorporated by reference. [Explanation of symbols]

[0331] 10. Imaging device 12 System Controller 16. Imaging device body 18 Interchangeable Lenses 18A Focus Ring 20 Image Sensor 22 Release button 24 Dial 26 Instruction keys 28 Display 30 Touch Panel 32 Touch Panel Display 36 Control device 37 First Actuator 38 Second Actuator 39 Third Actuator 40 Imaging lens 40A objective lens 40B variable magnification lens 40C aperture 40C1 opening 40C2 aperture blades 46 Image Memory 48 UI devices 50 External I / F 54 Photoelectric conversion element driver 55 ND filter driver 56 Motor Driver 58 Electronic ND Filter 60 Clear Glass 62 Shift mechanism 62A motor 64 processors 66 Storage 68 memory 70 Input / Output Interface 72 Photoelectric conversion element 72A Photosensitive surface 74 A / D converter 76 Reception Device 78 Hard key section 79 RAW images 80 frames 90 photometric values 91,110 Target transmittance calculation formula 92, 96, 118 Change time calculation formula 93 Split exposure calculation formula 94,100,116 Transmittance calculation formula 102 Adjustment value calculation formula 104,120,124 Exposure factor calculation formula 106 Aperture drive time calculation formula 107 Aperture value calculation formula 112 First Control 114 Second Control 119, 122 Predicted transmittance calculation formula A,A1 target frame count B, B1, B2, B3, B4, B5 Number of frames required B max1 ,B max2 ,B max3 Maximum number of frames EX div1 ,EX div2 ,EX div3 ,EX div4 ,EX div5 split exposure EX target target exposure FR Frame Rate FV Aperture value FV current Current aperture FV pred0 ,FV pred1 ,FV pred2 ,FV pred3 Predicted aperture FV target Target aperture OA optical axis PG Program SE Sensitivity SE current Current Sensitivity SE pred1 ,SE pred2 ,SE pred3 Predicted Shutter Speed SP Shutter Speed SP current Current shutter speed SP pred1 ,SP pred2 ,SP pred3 Predicted Shutter Speed T1, T2, T3, T4 change time T FV Aperture drive time TH1, TH2, TH3, TH4, TH5, TH6, TH7 thresholds TR transmittance TR current Current transmittance TR ideal1 Ideal transmittance TR InTime1 Transmittance during change time TR InTime2 Transmittance during operation TR mid intermediate transmittance TR pred1 ,TR pred2 ,TR pred3 Predicted transmittance TR real1 Reality Transmittance TR target Target transmission rate Δa Sensitivity adjustment value Δb Shutter speed adjustment value δ1, δ2, δ3 difference

Claims

1. a processor; The processor: The exposure of a plurality of frames obtained by capturing images using an imaging device having a movable diaphragm is controlled based on the transmittance of an electronic neutral density filter mounted on the imaging device and the driving time of the diaphragm. Control device.

2. The processor controls exposure of the plurality of frames by applying a plurality of divided exposures to the exposure of the plurality of frames, the divided exposures being determined according to a relationship between a change time required for the transmittance to change from a first transmittance to a second transmittance that can realize a target exposure of the image capture device and a drive time of the diaphragm. The control device according to claim 1 .

3. a first control is performed when the change time and the drive time exceed a first threshold value; The first control is a control that sets the change time within the drive time, and is a control that applies a plurality of first divided exposures, which are determined based on an actual change time that is a time it takes for the transmittance to actually change from the first transmittance to the second transmittance and the drive time, to exposure of the plurality of frames as the plurality of divided exposures. The control device according to claim 2 .

4. a second control is performed when the change time and / or the drive time is equal to or less than a first threshold value; The second control is a control for applying a plurality of second divided exposures, which are determined based on an ideal change time, which is a time required for an ideal change from the first transmittance to the second transmittance, and the drive time, to the exposure of the plurality of frames as the plurality of divided exposures. The control device according to claim 2 .

5. a first control is performed when the difference between the change time and the drive time exceeds a second threshold value; The first control is a control that sets the change time within the drive time, and is a control that applies a plurality of first divided exposures, which are determined based on an actual change time that is a time it takes for the transmittance to actually change from the first transmittance to the second transmittance and the drive time, to exposure of the plurality of frames as the plurality of divided exposures. The control device according to claim 2 .

6. When the difference between the change time and the drive time is equal to or less than a second threshold, a second control is performed. The second control is a control for applying a plurality of second divided exposures, which are determined based on an ideal change time, which is a time required for an ideal change from the first transmittance to the second transmittance, and the drive time, to the exposure of the plurality of frames as the plurality of divided exposures. The control device according to claim 2 .

7. The plurality of first divided exposures are determined based on the target exposure and a frame number determined based on a first frame number, which is the number of frames corresponding to the actual change time, and a second frame number, which is the number of frames corresponding to the drive time. The control device according to claim 3 .

8. The plurality of first divided exposures are determined based on a plurality of first actual transmittances that define a process of actual change from the first transmittance to the second transmittance within the actual change time, an aperture value of the aperture, and a sensitivity and / or a shutter speed that is set in the imaging device in accordance with the target exposure. The control device according to claim 7.

9. When the change time and the drive time exceed a third threshold value, a third transmittance is defined between the first transmittance and the second transmittance, such that the change time is within the drive time; The plurality of first actual transmittances are determined based on the first transmittance and the third transmittance. The control device according to claim 8.

10. When the difference between the change time and the drive time exceeds a fourth threshold value, a third transmittance is defined between the first transmittance and the second transmittance, such that the change time is within the drive time; The plurality of first actual transmittances are determined based on the first transmittance and the third transmittance. The control device according to claim 8.

11. The plurality of second divided exposures are determined based on the target exposure and a number of frames determined based on a third number of frames corresponding to the ideal change time and a fourth number of frames corresponding to the drive time. The control device according to claim 4.

12. The plurality of second divided exposures are determined based on a plurality of ideal transmittances that define a process of ideally changing from the first transmittance to the second transmittance within the ideal change time, an aperture value of the diaphragm, and a sensitivity and / or a shutter speed that is set in the imaging device in accordance with the target exposure. The control device according to claim 11.

13. When the change time and the drive time exceed a fifth threshold value, and a first difference, which is a difference between the fourth transmittance and the second transmittance that makes the change time within the drive time, exceeds a predetermined difference, The divided exposures in the process of changing from the first transmittance to the second transmittance among the plurality of divided exposures are determined based on a plurality of second actual transmittances that define a process of changing from the first transmittance to the second transmittance via a plurality of intermediate transmittances within the driving time, The maximum difference between the plurality of intermediate transmittances and the second transmittance is smaller than the first difference. The control device according to claim 2 .

14. When the difference between the change time and the drive time exceeds a sixth threshold value, and a first difference, which is a difference between a fourth transmittance that makes the change time within the drive time and the second transmittance, exceeds a predetermined difference, The divided exposures in the process of changing from the first transmittance to the second transmittance among the plurality of divided exposures are determined based on a plurality of second actual transmittances that define a process of changing from the first transmittance to the second transmittance via a plurality of intermediate transmittances within the driving time, The maximum difference between the plurality of intermediate transmittances and the second transmittance is smaller than the first difference. The control device according to claim 2 .

15. When the change time and the drive time exceed a seventh threshold, the first difference exceeds the predetermined difference, and a transmittance change time, which is a time required for the transmittance to change from the first transmittance to the fourth transmittance, is less than an eighth threshold, The divided exposures in the process of changing from the first transmittance to the second transmittance among the plurality of divided exposures are determined based on the plurality of second actual transmittances. The control device according to claim 13.

16. When the difference between the change time and the drive time exceeds a ninth threshold, the first difference exceeds the predetermined difference, and a transmittance change time, which is the time required for the transmittance to change from the first transmittance to the fourth transmittance, is less than a tenth threshold, The divided exposures in the process of changing from the first transmittance to the second transmittance among the plurality of divided exposures are determined based on the plurality of second actual transmittances. The control device according to claim 14.

17. The plurality of divided exposures are determined based on a fifth frame number, which is the number of frames required to change from the first transmittance to the second transmittance via the plurality of second actual transmittances, and a sixth frame number, which is the number of frames corresponding to the drive time, and the target exposure. The control device according to claim 15.

18. The plurality of divided exposures are determined based on a plurality of third actual transmittances that define a process in which the change time changes from the first transmittance to the second transmittance via the plurality of intermediate transmittances within the drive time, an aperture value of the diaphragm, and a sensitivity and / or a shutter speed that is set in the imaging device according to the target exposure. The control device of claim 17.

19. If the transmittance cannot follow the change in the aperture value of the diaphragm, The exposure of the plurality of frames is determined based on the first transmittance and the driving time. The control device according to claim 2 .

20. If the transmittance cannot follow the change in the aperture value of the diaphragm and the change in the aperture value is equal to or less than a first predetermined change amount, The exposure of the plurality of frames is determined based on the first transmittance and the driving time. The control device according to claim 2 .

21. If a change amount of the aperture value due to the aperture value being updated exceeds a second predetermined change amount while the exposure of the plurality of frames is being controlled, The exposure of the plurality of frames is updated in a manner according to the responsiveness of the transmittance to the degree of difference between the aperture value before the update and the aperture value after the update. The control device according to claim 2 .

22. The plurality of frames are obtained by performing the imaging based on a predetermined frame rate. The control device according to claim 1 .

23. A control device according to any one of claims 1 to 22; an image sensor used for the image capture; Imaging device.

24. and controlling the exposure of a plurality of frames obtained by capturing images using an imaging device having a movable diaphragm based on the transmittance of an electronic neutral density filter mounted on the imaging device and the driving time of the diaphragm. Control method.

25. A program for causing a computer to execute a process including controlling the exposure of multiple frames obtained by capturing images using an imaging device having a movable aperture, based on the transmittance of an electronic neutral density filter mounted on the imaging device and the operating time of the aperture.

Images