Lens unit, imaging system, lens unit operation method, and program

Abstract

A lens unit according to the present disclosure comprises an aperture with which the aperture value can be changed and a processor. The processor includes, as modes for controlling the aperture, a first mode for controlling the aperture by accepting an instruction from an imaging device and a second mode for controlling the aperture without accepting an instruction from the imaging device, and controls the aperture with the second mode when a received designated value for the aperture value is not included in a predetermined value set.

Description

Lens unit, imaging system, lens unit operation method, and program

[0001] The technology of the present disclosure relates to a lens unit, an imaging system, a method for operating the lens unit, and a program.

[0002] Japanese Patent Laid-Open Publication No. 2004-064518 discloses an optical device having an aperture unit with a variable aperture value, an operating member operable by a user, an instruction means for outputting an aperture instruction value in response to operation of the operating member, and a control means for generating a target aperture value from the aperture instruction value and controlling drive of the aperture unit based on the target aperture value. The control means performs a first process for generating a target aperture value with a first resolution from the aperture instruction value, and a second process for generating a target aperture value with a second resolution finer than the first resolution from the aperture instruction value.

[0003] Japanese Patent Application Laid-Open No. 2011-172145 discloses a camera that sets a program diagram with hysteresis characteristics that keeps the aperture from operating as much as possible by changing the sensitivity and shutter speed with priority over the aperture value, changes the amount of aperture change during live view depending on the difference between the target exposure level and the current exposure level, and changes the brightness tracking speed between the aperture drive region and the non-aperture drive region, thereby suppressing sudden fluctuations in the brightness of moving images captured during live view and improving image quality.

[0004] The technology of the present disclosure aims to provide a lens unit, an imaging system, a method for operating a lens unit, and a program that enable appropriate exposure settings to be made.

[0005] In order to achieve the above object, the lens unit of the present disclosure is a lens unit comprising an aperture whose aperture value can be changed, and a processor, wherein the processor controls the aperture using a first method in which the aperture is controlled by receiving instructions from the imaging device, and a second method in which the aperture is controlled without receiving instructions from the imaging device, and accepts a specified aperture value, and controls the aperture using the second method if the specified value is not included in a predetermined group of values.

[0006] If the designated value is included in the set of numerical values, the processor preferably controls the aperture using the first method based on the designated value.

[0007] It is preferable that an aperture operation member is provided, and the specified value is a value specified by operating the aperture operation member.

[0008] The imaging system of the present disclosure comprises a lens unit, an imaging device, and a processor, wherein the lens unit comprises an aperture that allows the aperture value to be changed, and the processor includes a first method for controlling the aperture by receiving instructions from the imaging device, and a second method for controlling the aperture without receiving instructions from the imaging device, and accepts a specified aperture value, and controls the aperture using the second method if the specified value is not included in a predetermined group of values.

[0009] When controlling the aperture using the second method, it is preferable that the processor calculates an exposure value based on the photometric value, determines the first exposure using a first numerical value that is closest to a specified value in the group of numerical values, and the exposure value, and changes the first exposure based on a first difference value between the specified value and the first numerical value.

[0010] It is preferable that the processor changes at least one of the shutter speed and the sensitivity based on the first difference value as the change in the first exposure.

[0011] It is preferable that the processor determines a second numerical value that is included in the group of numerical values ​​and is between the initial value and the specified value for each of the multiple imaging frames included in the period from the initial value at the time the aperture value is accepted to the specified value using the second method, determines a second exposure using the second numerical value and a divided exposure value obtained by dividing the exposure value, and changes the second exposure based on a second difference value between the current aperture value and the second numerical value.

[0012] Preferably, the processor modifies the second exposure by changing at least one of the shutter speed and the sensitivity based on the second difference value.

[0013] Preferably, the processor switches between the first and second methods based on whether the specified value is included in the set of numerical values.

[0014] It is preferable that the processor not switch between the first method and the second method when the change amount of the designated value is less than a specified value.

[0015] It is preferable that the processor switches between the first method and the second method when the amount of change is repeated a specified number of times or more and becomes less than a specified value.

[0016] Preferably, the processor maintains the exposure setting before the change if the change amount of the designated value is less than a specified value.

[0017] If the amount of change is not less than the specified value and the absolute value of the second difference value is greater than the threshold value, the processor preferably obtains the photometric value again and calculates the exposure value.

[0018] If the difference between the initial value and the designated value is equal to or greater than a specified value, the processor preferably controls the aperture using the first method and then switches to the second method.

[0019] It is preferable that the processor controls the aperture using the first method, and switches to the second method when the current value of the aperture value is the value closest to the specified value in the group of values ​​between the initial value and the specified value.

[0020] It is preferable that the processor calculates the time required for the aperture value to reach the specified value from the initial value at the time the specified value is accepted using the first method, and determines the number of frames included between the initial value and the specified value based on the required time.

[0021] The operating method of a lens unit disclosed herein is a method for operating a lens unit that includes an aperture that allows the aperture value to be changed and a processor, and includes a first method for controlling the aperture in response to an instruction from the imaging device, and a second method for controlling the aperture without receiving an instruction from the imaging device, in which the processor receives a specified aperture value, and if the specified value is not included in a predetermined group of values, controls the aperture using the second method.

[0022] The program disclosed herein is a program for operating a lens unit that includes an aperture whose aperture value can be changed and a processor, and includes a first method for controlling the aperture in response to instructions from an imaging device, and a second method for controlling the aperture without receiving instructions from the imaging device.The program accepts a specified aperture value, and if the specified value is not included in a predetermined group of values, causes the processor to execute processing to control the aperture using the second method.

[0023] FIG. 1 is a diagram illustrating an example of the configuration of an imaging system according to a first embodiment; FIG. 2 is a diagram schematically illustrating the appearance of a lens unit; FIG. 3 is a diagram illustrating a flow of exposure control during video shooting according to the first embodiment; FIG. 4 is a diagram illustrating first aperture control; FIG. 5 is a diagram illustrating first aperture control; FIG. 6 is a diagram illustrating second aperture control; FIG. 7 is a diagram illustrating second aperture control; FIG. 8 is a diagram illustrating a flow of first exposure control; FIG. 9 is a diagram illustrating an example of first exposure control; FIG. 10 is a diagram illustrating a flow of second exposure control; FIG. 11 is a diagram illustrating a flow of exposure control during video shooting according to the second embodiment; FIG. 12 is a diagram illustrating a flow of second exposure control; FIG. 13 is a diagram illustrating a flow of exposure control during video shooting according to the third embodiment; FIG. 14 is a diagram illustrating a flow of second exposure control according to the third embodiment; FIG. 15 is a diagram illustrating a flow of exposure control during video shooting according to the fourth embodiment; FIG. 16 is a diagram illustrating aperture control according to the fourth embodiment; FIG. 17 is a diagram illustrating a flow of first exposure control according to the fifth embodiment; FIG. 18 is a diagram illustrating a flow of first exposure control according to the fifth embodiment; FIG. 19 is a diagram illustrating a flow of processing for determining divided exposure values ​​according to the fifth embodiment; FIG. 19 is a diagram illustrating an example of processing for changing the exposure update period according to the fifth embodiment.

[0024] An example of an embodiment of the technology of the present disclosure will be described with reference to the accompanying drawings.

[0025] First, the terms used in the following description will be explained.

[0026] In the following description, "IC" is an abbreviation for "Integrated Circuit." "CPU" is an abbreviation for "Central Processing Unit." "ROM" is an abbreviation for "Read Only Memory." "RAM" is an abbreviation for "Random Access Memory." "CMOS" is an abbreviation for "Complementary Metal Oxide Semiconductor."

[0027] "FPGA" is an abbreviation for "Field Programmable Gate Array." "PLD" is an abbreviation for "Programmable Logic Device." "ASIC" is an abbreviation for "Application Specific Integrated Circuit."

[0028] In the following, the technology of the present disclosure will be described using an interchangeable lens digital camera as an example of an imaging system.

[0029] 1 shows an example of the configuration of an imaging system 10 according to the first embodiment. The imaging system 10 is composed of an imaging device 11 and a lens unit 12 that is replaceably attached to the imaging device 11. The lens unit 12 is attached to the front side of the imaging device 11 via an imaging device-side mount 11A and a lens unit-side mount 12A.

[0030] The imaging device 11 is provided with an operation device 13 that includes a dial, a release button, a touch panel, etc. and accepts operations by a user. The operation device 13 is operated by the user when setting an operation mode. The operation device 13 is also operated by the user when starting imaging.

[0031] A display 14 is provided on the rear side of the imaging device 11. The display 14 displays an image based on imaging data obtained by imaging (hereinafter referred to as a captured image), various menu screens, etc. The user can observe a live view image on the display 14 before starting imaging.

[0032] The imaging device 11 and the lens unit 12 are electrically connected by electrical contacts 11B provided on the imaging device side mount 11A coming into contact with electrical contacts 12B provided on the lens unit side mount 12A.

[0033] The lens unit 12 has an imaging optical system. The imaging optical system includes a zoom lens 30, a focus lens 31, and an aperture 32. The zoom lens 30, the focus lens 31, and the aperture 32 are arranged in this order from the subject side along an optical axis A. The zoom lens 30 and the focus lens 31 are movable in the direction of the optical axis A. Mechanisms for moving the zoom lens 30 and the focus lens 31 are not shown or described here. The type, number, and arrangement order of the lenses constituting the imaging optical system are not limited to the example shown in FIG.

[0034] The diaphragm 32 includes diaphragm blades 32A and a stepping motor 32B. The diaphragm blades 32A can open and close, and define an aperture diameter for adjusting the amount of light passing through the imaging optical system. The stepping motor 32B applies a driving force to the diaphragm blades 32A to change the aperture diameter. The aperture diameter corresponds to the aperture value. Therefore, the diaphragm 32 is capable of changing the aperture value.

[0035] The lens unit 12 is also provided with a processor 33, a memory 34, a driver 35, and an aperture ring 36. The memory 34 stores a program 37 for the processor 33 to perform processing, lens data 38 representing the characteristics of the lens unit 12, etc. The aperture ring 36 is an example of an "aperture operating member" according to the technology of the present disclosure.

[0036] The processor 33 is configured, for example, by a CPU, and is electrically connected to the processor 40 in the imaging device 11 via the electrical contacts 12B and 11B. The processor 33 changes the aperture value by stepping the stepping motor 32B via the driver 35. The stepping motor 32B is designed to change the aperture value by a predetermined number of steps (for example, 1 / 16 steps) each time it is driven by one step. The processor 33 can determine the aperture value of the aperture 32 from the number of steps by which the stepping motor 32B is driven.

[0037] The aperture ring 36 is a rotatable operating member that allows the user to specify an arbitrary aperture value for the aperture 32. The aperture ring 36 can be rotated within a movable range between two operating ends. The rotation position of the aperture ring 36 is detected by a rotation detection unit 36A. The rotation detection unit 36A is, for example, a magnetic sensor, and inputs the specified aperture value corresponding to the rotation position of the aperture ring 36 to the processor 33.

[0038] As shown in Figure 2, index lines indicating aperture values ​​are marked on the surface of the housing of the lens unit 12 near the aperture ring 36. In this embodiment, the index lines are marked at 1 / 3 stop intervals from the maximum aperture of F2.8 to the minimum aperture of F16. In addition, a mark M is marked on the aperture ring 36. The user can specify the aperture value by operating the aperture ring 36 and aligning the mark M with the desired index line.

[0039] The lens unit 12 is a so-called aperture de-click lens, which allows the aperture ring 36 to be rotated continuously without a clicking sensation. That is, the lens unit 12 allows an intermediate aperture value (e.g., F5.8) other than the aperture values ​​in 1 / 3-stop increments to be specified by operating the aperture ring 36. Aperture de-click lenses are particularly useful when shooting video because they allow the aperture value to be changed continuously.

[0040] The lens data 38 includes information on whether the lens unit 12 is an aperture de-click lens, the settable range of aperture values, etc. Note that the lens data 38 only includes data on aperture values ​​in 1 / 3 stop increments within the settable range of aperture values, because the amount of data would be enormous if data for all aperture values ​​were included.

[0041] The lens unit 12 may be a lens unit in which the aperture declick function can be switched between enabled and disabled using a selector switch (not shown).

[0042] The processor 33 has a first method and a second method for controlling the aperture 32 in a mode in which the user can manually specify the aperture value. The first method is a method for controlling the aperture 32 by receiving instructions from the image capture device 11. The second method is a method for controlling the aperture 32 without receiving instructions from the image capture device 11. Specifically, when the specified value is an aperture value in 1 / 3-stop increments, the processor 33 controls the aperture 32 in synchronization with exposure control by the image capture device 11 using the first method. When the specified value is an intermediate aperture value other than the aperture values ​​in 1 / 3-stop increments, the processor 33 controls the aperture 32 asynchronously with exposure control by the image capture device 11 (i.e., by the lens alone) using the second method.

[0043] Note that "without receiving an instruction from the imaging device 11" includes not only not receiving an aperture value from the imaging device 11, but also ignoring the aperture value received from the imaging device 11 and not using it for aperture control.

[0044] The group of aperture values ​​in 1 / 3-stop increments shown in FIG. 2 is an example of a "predetermined group of values" according to the technology of the present disclosure. The first method is executed when the specified value is included in the predetermined group of values. The second method is executed when the specified value is not included in the predetermined group of values. Note that the predetermined group of values ​​is not limited to the group of aperture values ​​in 1 / 3-stop increments, and may be another group of aperture values.

[0045] The imaging device 11 includes an imaging sensor 20, a signal processing unit 21, a processor 40, and a memory 42. The operations of the imaging sensor 20, the memory 42, the operation device 13, and the display 14 are controlled by the processor 40.

[0046] The processor 40 is configured by, for example, a CPU. The processor 40 executes various processes based on a program 43 stored in the memory 42. The memory 42 also stores lens data 38 that the processor 40 acquires from the lens unit 12.

[0047] The image sensor 20 is, for example, a CMOS image sensor. The image sensor 20 is positioned so that its optical axis A is perpendicular to the light-receiving surface 20A and is located at the center of the light-receiving surface 20A. Light that has passed through the lens unit 12 is incident on the light-receiving surface 20A. A plurality of pixels are formed on the light-receiving surface 20A, and each pixel generates a signal by performing photoelectric conversion. The image sensor 20 photoelectrically converts the light incident on each pixel to generate and output imaging data.

[0048] A color filter array, for example, in a Bayer pattern, is arranged on the light receiving surface of the image sensor 20, with a color filter of either R (red), G (green), or B (blue) being arranged opposite each pixel.

[0049] The image sensor 20 also has an electronic shutter function, which allows the shutter speed to be changed electronically. The image sensor 20 also has an amplifier that amplifies the image signal, which allows the ISO sensitivity (hereinafter simply referred to as sensitivity) to be changed. The shutter speed and sensitivity are controlled by the processor 40.

[0050] The signal processing unit 21 performs various signal processing, including demosaic processing, on the imaging data output from the imaging sensor 20. The processor 40 performs exposure calculations, including calculating photometric values, based on the signal-processed imaging data. The exposure corresponds to the brightness of the captured image and is determined by the aperture value, shutter speed, and sensitivity. The processor 40 also displays the signal-processed captured image on the display 14.

[0051] 3 shows the flow of exposure control during moving image shooting according to the first embodiment. The exposure control shown in FIG.

[0052] First, in step S1, the processor 40 determines whether or not the lens unit 12 attached to the imaging device 11 is an aperture declick lens. If the lens unit 12 attached has a switchable aperture declick function, and the aperture declick function is enabled, the processor 40 determines that the lens unit 12 attached to the imaging device 11 is an aperture declick lens. If the determination in step S1 is positive, the processor 40 proceeds to step S2, and if the determination is negative, the processor 40 proceeds to step S5.

[0053] In step S2, the processor 40 determines whether the set imaging mode is a predetermined mode. A predetermined mode is a mode in which the user can manually specify the aperture value, and includes, for example, M mode, A mode, etc. The M mode is a mode in which the user can specify the aperture value and shutter speed. The A mode is a mode in which the user can specify the aperture value. In the M mode, the sensitivity is adjusted by exposure control. In the A mode, at least one of the shutter speed and the sensitivity is adjusted by exposure control. If the determination in step S2 is positive, the processor 40 proceeds to step S3, and if the determination is negative, the processor 40 proceeds to step S5.

[0054] In step S3 , the processor 40 acquires the aperture value designated by operating the aperture ring 36 from the processor 33 of the lens unit 12 .

[0055] In step S4, the processor 40 determines whether the designated value acquired in step S3 is an intermediate aperture value. If the determination in step S4 is affirmative, the processor 40 proceeds to step S8, and if the determination is negative, the processor 40 proceeds to step S5.

[0056] In step S5, the processor 40 obtains the current aperture value from the processor 33 of the lens unit 12. Here, the current aperture value is the current aperture value of the aperture 32, and becomes the initial value for the first aperture control performed in step S6. The initial value is the aperture value of the aperture 32 at the time when the specified value is accepted. Note that it takes a certain amount of time for the aperture value of the aperture 32 to change from the initial value to the specified value.

[0057] In step S6, the processor 40 causes the processor 33 of the lens unit 12 to perform first aperture control. The first aperture control is aperture control according to the first method described above. In addition, while the first aperture control is being performed, the processor 40 performs first exposure control in step S7, and after completion of the first exposure control, the process proceeds to step S11. As will be described in more detail below, the first exposure control is exposure control synchronized with the first aperture control.

[0058] In step S8, the processor 40 acquires the current aperture value from the processor 33 of the lens unit 12. Step S8 is the same process as step S5. The current aperture value acquired in step S8 becomes the initial value for the first aperture control performed in step S6.

[0059] In step S9, the processor 40 causes the processor 33 of the lens unit 12 to perform second aperture control. The second aperture control is aperture control using the second method described above. During execution of the second aperture control, the processor 40 also executes second exposure control in step S10, and after completion of the second exposure control, the process proceeds to step S11. As will be described in more detail below, the second exposure control is exposure control that is asynchronous with the second aperture control.

[0060] In step S11, the processor 40 determines whether or not a termination condition is satisfied. For example, the termination condition may be that the user has performed an operation to terminate video capture. If the determination in step S11 is affirmative, the processor 40 terminates the process, and if the determination is negative, the processor 40 proceeds to step S3. That is, steps S3 to S10 are repeatedly executed until the determination in step S11 is affirmative.

[0061] 4 and 5 illustrate the first aperture control. Fig. 4 shows a case where the user operates the aperture ring 36 to specify the aperture value as F5.6. In this case, F5.6 is an aperture value in 1 / 3 stop increments and is not an intermediate aperture value, so the first aperture control is performed.

[0062] 5, the processor 33 of the lens unit 12 receives instructions from the processor 40 of the imaging device 11 to control the aperture 32 and change the aperture value from F2.8 (initial value) to F5.6 (specified value) during an exposure update period T of six frames. Note that frame number 0 represents the current imaging frame, and F2.8 is the current aperture value acquired in step S5 above. An imaging frame refers to one imaging cycle by the imaging sensor 20. Hereinafter, an imaging frame will simply be referred to as a frame.

[0063] The aperture values ​​that processor 40 instructs processor 33 in the first aperture control are aperture values ​​in 1 / 3-stop increments. That is, the aperture values ​​set for each frame of the exposure update period T are aperture values ​​in 1 / 3-stop increments. In this way, in the first aperture control, processor 40 instructs processor 33 to set, for each frame, a numerical value that is included in a group of aperture values ​​in 1 / 3-stop increments (a group of predetermined numerical values) and that is between the initial value and the specified value.

[0064] 6 and 7 illustrate the second aperture control. Fig. 6 shows a case where the user operates the aperture ring 36 to specify the aperture value as F5.8. In this case, F5.8 is an intermediate aperture value, not an aperture value in 1 / 3-stop increments, so the second aperture control is performed.

[0065] 7, the processor 33 of the lens unit 12 controls the aperture 32 without receiving instructions from the processor 40 of the imaging device 11, and changes the aperture value from F2.8 (initial value) to F5.8 (specified value) during an exposure update period T of six frames. Note that frame number 0 indicates the current frame, and F2.8 is the current aperture value obtained in step S8 above.

[0066] In the second aperture control, the processor 33 controls the aperture 32 so that the aperture value gradually changes from the initial value to a specified value during the exposure update period T. Therefore, in most cases, the aperture value set for each frame of the exposure update period T is not a value included in the group of aperture values ​​(a group of predetermined values) in 1 / 3 stop increments, but an intermediate aperture value.

[0067] In the first aperture control and the second aperture control, changing the aperture value from the initial value to the designated value in a period of one frame results in a large change in exposure, so the aperture value is changed from the initial value to the designated value in an exposure update period T of multiple frames. The number of frames included in the exposure update period T may be changed as appropriate.

[0068] Fig. 8 shows the flow of the first exposure control. Fig. 9 shows an example of the first exposure control when the aperture value is set to F5.6 as shown in Fig. 4. Steps S100 to S105 shown in Fig. 8 are executed in the current frame with frame number 0. Steps S106 to S109 are executed during the exposure update period T.

[0069] First, in step S100, the processor 40 acquires the imaging data output from the imaging sensor 20 via the signal processing unit 21. In step S101, the processor 40 calculates a photometric value based on the acquired imaging data. In step S102, the processor 40 calculates a target exposure value based on the calculated photometric value. The target exposure value corresponds to the target brightness of the captured image.

[0070] In step S103, the processor 40 calculates the aperture value in 1 / 3-stop increments that is closest to the specified value specified by the user operating the aperture ring 36. In the first exposure control, the specified value is not an intermediate aperture value, so the specified value is an aperture value in 1 / 3-stop increments. Note that in the first exposure control, step S103 does not have to be executed.

[0071] In step S104, processor 40 determines a plurality of split exposure values ​​for split exposure setting based on the calculated target exposure value. "11 EV" for frame number 6 shown in Figure 9 is the target exposure value. The exposure values ​​for frames 1 to 5 are split exposure values ​​obtained by dividing the target exposure value.

[0072] In step S105, the processor 40 determines a plurality of aperture values ​​for the divided exposure setting based on the designated value, and instructs the processor 33 of the lens unit 12 to set the determined plurality of aperture values ​​for each frame of the exposure update period T.

[0073] In step S106, the processor 40 selects an aperture value for the next frame from the determined aperture values. For example, if the current frame number is 0, the processor 40 selects the aperture value for frame number 1 (F3.2 in the example shown in FIG. 9).

[0074] In step S107, the processor 40 determines the shutter speed and sensitivity based on the selected aperture value. That is, the processor 40 determines the exposure. In the example shown in Fig. 9, the aperture value is determined in step S105 according to the exposure value of each frame, so the shutter speed and sensitivity are fixed values.

[0075] In step S108, the processor 40 sets the exposure for the next frame. Specifically, the processor 40 sets the aperture value, shutter speed, and sensitivity at the start of the next frame.

[0076] In step S109, the processor 40 determines whether the frame for which exposure setting was performed is the final frame (frame number 6 in the example shown in FIG. 9 ). If the determination in step S109 is positive, the processor 40 ends the process. If the determination is negative, the processor 40 proceeds to step S106.

[0077] Fig. 10 shows the flow of the second exposure control. Fig. 11 shows an example of the second exposure control when the aperture value is set to F5.8 as shown in Fig. 6. Steps S200 to S205 shown in Fig. 10 are executed in the current frame with frame number 0. Steps S206 to S212 are executed during the exposure update period T.

[0078] Steps S200 to S202 are the same as steps S100 to S102 described above. In step S203, the processor 40 calculates the aperture value in 1 / 3-stop increments that is closest to the designated value specified by the user by operating the aperture ring 36. In the example shown in Fig. 11, the processor 40 calculates F5.6 as the aperture value in 1 / 3-stop increments that is closest to the designated value of F5.8. F5.6 is an example of a "first numerical value," which is the numerical value closest to the designated value from a predetermined group of numerical values.

[0079] In step S204, processor 40 determines a plurality of split exposure values ​​for split exposure setting based on the target exposure value calculated in step S202. "11EV" for frame number 6 shown in Figure 11 is the target exposure value. The exposure values ​​for frames 1 to 5 are split exposure values ​​obtained by dividing the target exposure value.

[0080] In step S205, the processor 40 determines multiple aperture values ​​for the split exposure setting based on the aperture value (first numerical value) in 1 / 3-stop increments closest to the specified value. The aperture values ​​determined by the processor 40 in step S205 are the aperture values ​​in 1 / 3-stop increments for frame numbers 1 to 5 shown in FIG. 11. These aperture values ​​in 1 / 3-stop increments are "second numerical values" that are included in a predetermined set of numerical values ​​and are between the initial value and the specified value. Note that, unlike the first exposure control, the processor 40 does not instruct the processor 33 of the lens unit 12 about the multiple aperture values ​​determined in step S205. This is because the processor 33 of the lens unit 12 controls the aperture 32 without receiving instructions from the imaging device 11.

[0081] In step S206, the processor 40 selects an aperture value for the next frame from the plurality of aperture values ​​determined in step S205. For example, if the current frame number is 0, the processor 40 selects the aperture value for frame number 1 (F3.2 in the example shown in FIG. 11).

[0082] In step S207, the processor 40 determines the shutter speed and sensitivity based on the selected aperture value. That is, the processor 40 provisionally determines the exposure. In the example shown in FIG. 11 , the aperture value (in 1 / 3-stop increments) is determined in step S205 according to the exposure value of each frame, so the shutter speed and sensitivity are fixed. The exposure for frame number 6 shown in FIG. 11 corresponds to the "first exposure determined using the first numerical value and the target exposure value," while the exposures for frames 1 to 5 correspond to the "second exposure determined using the first numerical value and the divided exposure value." Thus, in the second exposure control, the processor 40 first provisionally determines the exposure based on the aperture values ​​in 1 / 3-stop increments included in the lens data 38, regardless of the actual aperture value of the aperture 32.

[0083] In step S208, the processor 40 acquires the current aperture value at the start of the next frame from the processor 33 of the lens unit 12. This is because the aperture value used to determine the tentative exposure differs from the actual aperture value at the start of the next frame.

[0084] In step S209, the processor 40 calculates a differential exposure value. The differential exposure value is the difference between the aperture value used to determine the provisional exposure and the actual aperture value, and the exposure value corresponding to the differential value. The difference between the designated value (F5.8) and the first numerical value (F5.6) shown in FIG. 11 is the first differential value. The differences between the other current aperture values ​​(F3.3, F3.8, F4.2, F4.8, F5.3) and the second numerical values ​​(F3.2, F3.5, F4.0, F4.5, F5.0) are the second differential values.

[0085] In step S210, the processor 40 changes the exposure provisionally determined in step S207 based on the calculated differential exposure value. In other words, the processor 40 changes the first exposure based on the first differential value, and changes the second exposure based on the second differential value. In the example shown in FIG. 11, the exposure is changed by changing the sensitivity based on the differential exposure values ​​ΔEV1 to ΔEV6. α1 to α6 are the amount of change in sensitivity. Note that the exposure may also be changed by changing the shutter speed.

[0086] In step S211, the processor 40 sets the exposure for the next frame. Specifically, the processor 40 sets the exposure (shutter speed and sensitivity) changed in step S210 at the timing when the next frame starts. The aperture value is set by the processor 33 of the lens unit 12.

[0087] In step S212, the processor 40 determines whether the frame for which exposure setting was performed is the final frame (frame number 6 in the example shown in FIG. 11 ). If the determination in step S212 is affirmative, the processor 40 ends the process, and if the determination is negative, the processor 40 proceeds to step S206.

[0088] As described above, in the second exposure control, the specified value is an intermediate aperture value, but the exposure is provisionally set based on the aperture value in 1 / 3-stop increments included in the lens data 38, and then the exposure is changed based on the difference between the aperture value in 1 / 3-stop increments and the actual aperture value set by the lens unit 12 alone.

[0089] In this embodiment, the aperture control methods include a first method for controlling the aperture 32 in response to an instruction from the imaging device 11 and a second method for controlling the aperture 32 without receiving an instruction from the imaging device 11. The processor 33 accepts a specified aperture value and controls the aperture 32 using the second method if the specified value is not included in a predetermined set of values. When controlling the aperture 32 using the second method, the processor 40 calculates an exposure value based on a photometric value, determines a first exposure using a first value that is closest to the specified value from the set of values, and the exposure value, and changes the first exposure based on a first difference between the specified value and the first value. This allows for appropriate exposure setting even when the specified value is an intermediate aperture value that is not included in the predetermined set of values. In other words, even when an intermediate aperture value that is not included in the lens data 38 is specified, the brightness of the captured image can be maintained at an appropriate value. Furthermore, the size of the lens data 38 can be reduced.

[0090] Furthermore, the processor 40 determines a second numerical value that is included in the set of numerical values ​​and that is between the initial value and the specified value for each of the multiple captured frames included in the period from the initial value at the time the aperture value is accepted to the specified value using the second method, determines a second exposure using the second numerical value and a split exposure value obtained by dividing the target exposure value, and changes the second exposure based on a second difference value between the current aperture value and the second numerical value, so that split exposure setting can be performed appropriately even when an intermediate aperture value that is not included in the lens data 38 is specified. Furthermore, the brightness of the captured image when split exposure setting is used can be changed appropriately.

[0091] The processor 33 and the processor 40 are examples of the "processor" according to the technology of the present disclosure. Either the processor 33 or the processor 40 may execute the above processing. Furthermore, the processor 33 and the processor 40 may be configured as a single processor.

[0092] Second Embodiment Next, a second embodiment of the present disclosure will be described. The second embodiment differs from the first embodiment in part of exposure control during video shooting. In the first embodiment, even if the user slightly changes the designated value by operating the aperture ring 36, the aperture control method may switch if the designated value is near an aperture value in 1 / 3-stop increments. When the aperture control method switches, brightness fluctuations (so-called hunting) may occur. The purpose of this embodiment is to suppress brightness fluctuations.

[0093] 12 and 13 show the flow of exposure control during video shooting according to the second embodiment. The flow shown in Figures 12 and 13 differs from the flow shown in Figure 3 only in that steps S20 to S26 have been added.

[0094] In this embodiment, if the determination in step S4 is affirmative, the processor 40 acquires the current aperture value in step S8 and proceeds to step S20. In step S20, the processor 40 determines whether the previous aperture control method was the first method (i.e., first aperture control). If the determination in step S20 is affirmative, the processor 40 proceeds to step S21, and if the determination is negative, the processor 40 proceeds to step S9.

[0095] That is, if the previous aperture drive method was the second method and the current method will also be the second method, the processor 40 executes step S9 as in the first embodiment. On the other hand, if the previous aperture drive method was the first method and it is determined that the current method will be switched to the second method, the processor 40 executes step S21 before switching.

[0096] In step S21, the processor 40 determines whether the change amount of the designated value is less than a specified value. The change amount of the designated value is the difference between the designated value acquired in step S3 and the current aperture value acquired in step S8. If the determination in step S21 is positive, the processor 40 proceeds to step S22, and if the determination is negative, the processor 40 proceeds to step S9. That is, if the change amount of the designated value is equal to or greater than the specified value, the processor 40 switches the aperture drive method to the second method (i.e., second aperture control).

[0097] In step S22, the processor 40 determines whether the change amount of the designated value is less than the specified value after repeated a specified number of times. If the determination in step S22 is affirmative, the processor 40 proceeds to step S9, and if the determination is negative, the processor 40 proceeds to step S6. That is, even if the change amount of the designated value is less than the specified value, if the change amount is less than the specified value after repeated a specified number of times, the processor 40 switches the aperture drive method to the second method. On the other hand, if the change amount of the designated value is not less than the specified value after repeated a specified number of times, the processor 40 does not switch the aperture drive method and maintains the first method.

[0098] If the determination in step S4 is negative, the processor 40 acquires the current aperture value in step S23 and proceeds to step S24. In step S24, the processor 40 determines whether the previous aperture control method was the second method (i.e., second aperture control). If the determination in step S24 is positive, the processor 40 proceeds to step S25, and if the determination is negative, the processor 40 proceeds to step S6.

[0099] That is, if the previous aperture drive method was the first method and the current method will also be the first method, the processor 40 executes step S6 as in the first embodiment. On the other hand, if the previous aperture drive method was the second method and it is determined that the current method will be switched to the first method, the processor 40 executes step S25 before switching.

[0100] In step S25, the processor 40 determines whether the change amount of the designated value is less than a specified value. Here, the change amount of the designated value is the difference between the designated value acquired in step S3 and the current aperture value acquired in step S23. If the determination in step S25 is positive, the processor 40 proceeds to step S26, and if the determination is negative, the processor 40 proceeds to step S6. That is, if the change amount of the designated value is equal to or greater than the specified value, the processor 40 switches the aperture drive method to the first method (i.e., first aperture control).

[0101] In step S26, the processor 40 determines whether the change amount of the designated value is less than the specified value after repeated changes of the designated value a specified number of times or more. If the determination in step S26 is affirmative, the processor 40 proceeds to step S6, and if the determination is negative, the processor 40 proceeds to step S9. That is, even if the change amount of the designated value is less than the specified value, if the change amount is less than the specified value after repeated changes of the designated value a specified number of times or more, the processor 40 switches the aperture drive method to the first method. On the other hand, if the change amount of the designated value is not less than the specified value after repeated changes of the designated value a specified number of times or more, the processor 40 does not switch the aperture drive method and uses the second method.

[0102] As described above, in the second embodiment, even if the user changes the designated value by operating the aperture ring 36, if the change in the designated value is less than the specified value, switching between the first and second methods is not performed, so that brightness fluctuations caused by frequent switching of the aperture drive method can be suppressed.

[0103] Third Embodiment Next, a third embodiment of the present disclosure will be described. The third embodiment differs from the first embodiment in part of the second exposure control. In the first embodiment, even if the user slightly changes the designated value by operating the aperture ring 36, the exposure setting is changed in the second exposure control. If the exposure setting is changed every time the designated value is slightly changed, brightness fluctuations (so-called hunting) may occur in the captured image. The purpose of this embodiment is to suppress brightness fluctuations due to the second exposure control.

[0104] Figures 14 and 15 show the flow of the second exposure control according to the third embodiment. The flow shown in Figures 14 and 15 differs from the flow shown in Figure 10 only in that steps S300 to S307 are added.

[0105] In this embodiment, after calculating the target exposure value in step S202, processor 40 determines in step S300 whether the target exposure value has been recalculated. Specifically, processor 40 determines whether the calculation of the target exposure value in step S202 was a recalculation based on a determination described below. If the determination in step S300 is positive, processor 40 proceeds to step S301, and if the determination is negative, processor 40 proceeds to step S203.

[0106] In step S301 , the processor 40 acquires the designated value of the aperture value designated by operating the aperture ring 36 from the processor 33 of the lens unit 12 .

[0107] In step S203, the processor 40 calculates the aperture value in 1 / 3 stop increments closest to the specified value obtained in step S3, or, if step S301 is executed, the aperture value in 1 / 3 stop increments closest to the specified value obtained in step S301.

[0108] In step S303, the processor 40 calculates the aperture value closest to the current aperture value in 1 / 3-stop increments. In step S304, the processor 40 determines whether the aperture value calculated in step S203 is equal to the aperture value calculated in step S303. If the determination in step S304 is positive, the processor 40 proceeds to step S305, and if the determination is negative, the processor 40 proceeds to step S204.

[0109] In step S305, the processor 40 determines whether the change amount of the designated value is less than a specified value. Here, the change amount of the designated value is the difference between the designated value acquired in step S3 or step S301 and the current aperture value. If the determination in step S305 is positive, the processor 40 proceeds to step S306, and if the determination is negative, the processor 40 proceeds to step S204.

[0110] In step S306, the processor 40 ends the process while maintaining the current exposure setting. That is, if the change amount of the designated value is less than the specified value, the processor 40 does not change the exposure setting.

[0111] Steps S204 to S209 are the same as those in the first embodiment. After calculating the differential exposure value in step S209, the processor 40 determines in step S307 whether the absolute value of the differential exposure value is greater than a threshold value. The determination in step S307 corresponds to determining whether the absolute value of the second differential value described above is greater than a threshold value. If the determination in step S305 is positive, the processor 40 proceeds to step S200; if the determination is negative, the processor 40 proceeds to step S210. That is, if the absolute value of the second differential value is greater than the threshold value, the processor 40 acquires a photometric value again and recalculates the target exposure value.

[0112] Steps S210 to S212 are the same as those in the first embodiment.

[0113] In this embodiment, if the change in the designated value is less than the specified value, the exposure setting before the change is maintained, thereby suppressing fluctuations in brightness of the captured image. Also, if the absolute value of the second difference value is greater than the threshold, the photometric value is acquired again, thereby making it possible to appropriately change the brightness of the captured image when using the split exposure setting.

[0114] Fourth Embodiment Next, a fourth embodiment of the present disclosure will be described. The fourth embodiment differs from the first embodiment in some aspects of exposure control during video capture. In the first embodiment, when the specified value is an intermediate aperture value, the aperture value is changed to the specified value by the second aperture control. The second aperture control is asynchronous with the exposure control by the imaging device 11, and therefore, tracking of the aperture value is slow. Therefore, if the aperture ring 36 is operated by a large amount and the difference between the initial value and the specified value is large, tracking may be delayed if the brightness of the subject changes during aperture value control, potentially resulting in fluctuations in the brightness of the captured image. In this embodiment, the objective is to increase the tracking speed of the aperture value in response to brightness fluctuations in the second aperture control.

[0115] 16 and 17 show the flow of exposure control during video shooting according to the fourth embodiment. The flow shown in Figures 16 and 17 differs from the flow shown in Figure 3 only in that steps S30 to S34 have been added.

[0116] In this embodiment, after acquiring the current aperture value in step S8, the processor 40 determines in step S30 whether the difference between the initial value and the designated value is equal to or greater than a specified value. The initial value is the current aperture value acquired in step S8. If the determination in step S30 is affirmative, the processor 40 proceeds to step S31, and if the determination is negative, the processor 40 proceeds to step S9.

[0117] In step S31, the processor 40 sets the aperture value closest to the designated value in 1 / 3-stop increments between the initial value and the designated value as the specific value. For example, as shown in Fig. 18, if the designated value is F8.5, the specific value is F8.0. The specific value corresponds to the value between the initial value and the designated value that is closest to the designated value in a predetermined group of values ​​for the current aperture value.

[0118] After setting the specific value in step S31, the processor 40 executes first aperture control and first exposure control in steps S32 and S33. The first aperture control and first exposure control in steps S32 and S33 are the same as the first aperture control and first exposure control in the first embodiment. In step S34, the processor 40 determines whether the aperture value of the aperture 32 has reached the specific value through the first aperture control. If the determination in step S34 is affirmative, the processor 40 proceeds to step S9, and if the determination is negative, the processor 40 proceeds to step S32.

[0119] 18, the processor 40 executes the first aperture control and the first exposure control during the period from when the aperture value reaches the initial value to when it reaches the specific value, and executes the second aperture control and the second exposure control during the period from when the aperture value reaches the specific value to when it reaches the designated value.

[0120] In this embodiment, when the difference between the initial value and the specified value is equal to or greater than a specified value, the processor 40 controls the aperture 32 using the first method, and then switches to the second method. In particular, the processor 40 controls the aperture using the first method, and switches to the second method when the current value of the aperture 32 is the value closest to the specified value in a predetermined group of values ​​between the initial value and the specified value. The first method has a faster aperture value tracking speed in response to brightness fluctuations than the second method, and is therefore able to suppress brightness fluctuations due to tracking delays.

[0121] Fifth Embodiment Next, a fifth embodiment of the present disclosure will be described. The fifth embodiment differs from the first embodiment in part of the first exposure control. In the first embodiment, the exposure update period T is fixed. In this embodiment, the exposure update period T is changed depending on the time required for the aperture value of the diaphragm 32 to reach a specified value from the initial value.

[0122] Figures 19 to 21 show the flow of the first exposure control according to the fifth embodiment. The flows shown in Figures 19 and 20 differ from the flow shown in Figure 8 in that steps S400 to S405 are added, and in that multiple divided exposure values ​​are determined in consideration of the required time in step S104.

[0123] 21 shows the flow of the process for determining divided exposure values ​​according to the fifth embodiment. In step S1040, the processor 40 calculates the time required for the aperture value of the diaphragm 32 to reach the specified value from the initial value. In step S1041, the processor 40 calculates the number of frames corresponding to the calculated required time.

[0124] In step S1042, the processor 40 determines whether the calculated number of frames (hereinafter referred to as the calculated number of frames) is the same as the updated number of frames. The updated number of frames is a predetermined number of frames included in the exposure update period T. If the determination in step S1042 is positive, the processor 40 proceeds to step S1044, and if the determination is negative, the processor 40 proceeds to step S1043.

[0125] In step S1043, the processor 40 sets the calculated number of frames as the number of updated frames. That is, if the calculated number of frames and the updated number of frames differ, the processor 40 changes the length of the exposure update period T to a length corresponding to the calculated number of frames.

[0126] In step S1044, the processor 40 determines a plurality of divided exposure values ​​for setting divided exposure in the same manner as in step S104 of the first embodiment.

[0127] After setting the exposure for the next frame in step S108 shown in Fig. 19, the processor 40 acquires imaging data in step S400 shown in Fig. 20. In step S401, the processor 40 calculates a photometric value based on the acquired imaging data.

[0128] In step S402, the processor 40 calculates a differential exposure value, which corresponds to the difference between the photometric value calculated in step S101 and the photometric value calculated in step S401, i.e., the amount of variation in brightness.

[0129] In step S403, the processor 40 determines whether the absolute value of the differential exposure value is greater than the threshold value. If the determination in step S305 is affirmative, the processor 40 proceeds to step S404. If the determination is negative, the processor 40 proceeds to step S109.

[0130] In step S404, the processor 40 calculates a target exposure value based on the photometric value calculated in step S401. In step S405, the processor 40 acquires the designated aperture value specified by operating the aperture ring 36. After step S405, the processor 40 proceeds to step S103. That is, in this embodiment, if the amount of variation in brightness is large, the processor 40 recalculates the target exposure value and reacquires the designated value.

[0131] 22 shows how the exposure update period T is changed when the calculated number of frames becomes 6 when the number of update frames is 9. The aperture value after the change is determined to be changed linearly, for example.

[0132] In this embodiment, the exposure update period T is changed according to the time required for the aperture value to reach the specified value from the initial value, and the target exposure value is recalculated when the amount of fluctuation in brightness is large, thereby suppressing fluctuations in brightness.

[0133] In the above-described embodiments, the hardware structure of the processor, such as the processors 33 and 40, may be any of the various configurations shown below. The processors include a CPU, which is a general-purpose processor that functions by executing software (programs), as well as a processor such as an FPGA, whose circuit configuration can be changed after manufacture. An FPGA includes a dedicated electric circuit, such as a PLD or an ASIC, that has a circuit configuration designed specifically for executing a specific process.

[0134] The processor may be one of these various processors, or may be 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).Furthermore, multiple processors may be configured as a single processor.

[0135] There are several possible examples of configuring multiple processors with a single processor. A first example is a form in which one processor is configured with a combination of one or more CPUs and software, as typified by computers such as client and server. A second example is a form in which a processor is used to realize the functions of an entire system on a single IC chip, as typified by systems on chips (SOCs).

[0136] Furthermore, more specifically, the hardware structure of these various processors can be an electric circuit that combines circuit elements such as semiconductor elements.

[0137] The program may also be stored in a non-transitory computer-readable storage medium.

[0138] The above-described description and illustrations are a detailed explanation of the parts related to the technology of the present disclosure and are merely an example of the technology 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 technology of the present disclosure. Therefore, it goes without saying that unnecessary parts may be deleted, new elements may be added, or replacements may be made to the above-described description and illustrations within the scope of the gist of the technology of the present disclosure. Furthermore, to avoid confusion and facilitate understanding of the parts related to the technology of the present disclosure, the above-described description and illustrations omit explanations of common technical knowledge that do not require particular explanation to enable the implementation of the technology of the present disclosure.

[0139] 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.

[0140] The above description allows the understanding of the following technologies. [Supplementary Item 1] A lens unit comprising an aperture whose aperture value is variable and a processor, wherein the processor includes, as methods for controlling the aperture, a first method for controlling the aperture in response to an instruction from an imaging device and a second method for controlling the aperture without receiving an instruction from the imaging device, and receives a designated value for the aperture value, and controls the aperture using the second method if the designated value is not included in a predetermined group of values. [Supplementary Item 2] The lens unit according to Supplementary Item 1, wherein, if the designated value is included in the group of values, the processor controls the aperture using the first method based on the designated value. [Supplementary Item 3] The lens unit according to Supplementary Item 1 or Supplementary Item 2, comprising an aperture operation member, and the designated value is a value designated by operating the aperture operation member. [Supplementary Item 4] An imaging system comprising a lens unit, an imaging device, and a processor, wherein the lens unit has an aperture with a variable aperture value, wherein the processor controls the aperture using a first method of controlling the aperture in response to an instruction from the imaging device and a second method of controlling the aperture without receiving an instruction from the imaging device, wherein the processor accepts a specified aperture value, and controls the aperture using the second method if the specified value is not included in a predetermined group of values. [Supplementary Item 5] The imaging system described in Supplementary Item 4, wherein, when controlling the aperture using the second method, the processor calculates an exposure value based on a photometric value, determines a first exposure using the exposure value and a first numerical value that is a numerical value in the group of values ​​closest to the specified value, and changes the first exposure based on a first difference value between the specified value and the first numerical value. [Supplementary Item 6] The imaging system described in Supplementary Item 5, wherein, to change the first exposure, the processor changes at least one of a shutter speed and a sensitivity based on the first difference value.[Supplementary Item 7] The imaging system according to Supplementary Item 5 or Supplementary Item 6, wherein the processor determines a second numerical value that is included in the set of numerical values ​​and is between the initial value and the specified value for each of a plurality of imaging frames included in the period from the initial value at the time the specified value is accepted until the aperture value reaches the specified value in the second method, determines a second exposure using the second numerical value and a divided exposure value obtained by dividing the exposure value, and changes the second exposure based on a second difference value between the current aperture value and the second numerical value. [Supplementary Item 8] The imaging system according to Supplementary Item 7, wherein the processor changes the second exposure by changing at least one of the shutter speed and the sensitivity based on the second difference value. [Supplementary Item 9] The imaging system according to any one of Supplementary Items 4 to 8, wherein the processor switches between the first method and the second method based on whether the specified value is included in the set of numerical values. [Supplementary Item 10] The imaging system of Supplementary Item 9, wherein the processor does not switch between the first method and the second method if the amount of change in the designated value is less than a specified value. [Supplementary Item 11] The imaging system of Supplementary Item 10, wherein the processor switches between the first method and the second method if the amount of change is repeated a specified number of times or more and becomes less than the specified value. [Supplementary Item 12] The imaging system of Supplementary Item 7 or Supplementary Item 8, wherein the processor maintains the exposure setting before the change if the amount of change in the designated value is less than the specified value. [Supplementary Item 13] The imaging system of Supplementary Item 12, wherein the processor acquires a photometric value again and calculates the exposure value if the amount of change is not less than the specified value and the absolute value of the second difference value is greater than a threshold. [Supplementary Item 14] The imaging system of any one of Supplementary Items 7 to 13, wherein the processor controls the aperture using the first method and then switches to the second method if the difference between the initial value and the designated value is greater than or equal to a specified value.[Supplementary Item 15] The imaging system according to Supplementary Item 14, wherein the processor controls the aperture using the first method, and switches to the second method when the current value of the aperture value becomes a value between the initial value and the specified value that is closest to the specified value in the group of values. [Supplementary Item 16] The imaging system according to any one of Supplementary Items 4 to 15, wherein the processor calculates a required time for the aperture value to reach the specified value from the initial value at the time the specified value is accepted using the first method, and determines the number of frames included between the initial value and the specified value based on the required time.

Claims

1. A lens unit comprising an aperture whose aperture value can be changed, and a processor, wherein the processor controls the aperture using a first method for controlling the aperture in response to an instruction from an imaging device, and a second method for controlling the aperture without receiving an instruction from the imaging device, and receives a designated aperture value, and controls the aperture using the second method if the designated value is not included in a predetermined group of values.

2. The lens unit according to claim 1, wherein the processor controls the aperture in the first manner based on the designated value when the designated value is included in the set of numerical values.

3. The lens unit according to claim 1, further comprising an aperture operation member, wherein the specified value is a value specified by operating the aperture operation member.

4. An imaging system comprising a lens unit, an imaging device, and a processor, wherein the lens unit has an aperture whose aperture value is changeable, and the processor includes, as methods for controlling the aperture, a first method for controlling the aperture by receiving an instruction from the imaging device, and a second method for controlling the aperture without receiving an instruction from the imaging device, and receives a specified value for the aperture value, and controls the aperture by the second method if the specified value is not included in a predetermined group of values.

5. The imaging system of claim 4, wherein, when the processor controls the aperture using the second method, it calculates an exposure value based on a photometric value, determines a first exposure using a first numerical value that is closest to the specified value in the group of numerical values ​​and the exposure value, and changes the first exposure based on a first difference value between the specified value and the first numerical value.

6. The imaging system according to claim 5, wherein the processor changes at least one of a shutter speed and a sensitivity based on the first difference value as the change in the first exposure.

7. The imaging system described in claim 5, wherein the processor determines a second numerical value that is included in the group of numerical values ​​and is between the initial value and the specified value for each of a plurality of imaging frames included in the period from when the aperture value receives the specified value until it reaches the specified value in the second method, determines a second exposure using the second numerical value and a divided exposure value obtained by dividing the exposure value, and changes the second exposure based on a second difference value between the current aperture value and the second numerical value.

8. The imaging system according to claim 7, wherein the processor changes the second exposure by changing at least one of a shutter speed and a sensitivity based on the second difference value.

9. The imaging system according to claim 4, wherein the processor switches between the first method and the second method based on whether the specified value is included in the set of numerical values.

10. The imaging system according to claim 9, wherein the processor does not switch between the first method and the second method when the change amount of the designated value is less than a specified value.

11. The imaging system according to claim 10, wherein the processor switches between the first method and the second method when the amount of change is repeated a specified number of times or more and becomes less than the specified value.

12. The imaging system according to claim 7, wherein the processor maintains the exposure setting before the change if the change amount of the designated value is less than a specified value.

13. The imaging system according to claim 12, wherein the processor, when the amount of change is not less than the specified value and the absolute value of the second difference value is greater than a threshold value, acquires a photometric value again and calculates the exposure value.

14. The imaging system according to claim 7, wherein the processor controls the aperture using the first method and then switches to the second method when the difference between the initial value and the specified value is equal to or greater than a specified value.

15. The imaging system of claim 14, wherein the processor controls the aperture using the first method, and switches to the second method when the current value of the aperture value becomes the value closest to the specified value in the group of values ​​between the initial value and the specified value.

16. The imaging system of claim 4, wherein the processor calculates the time required for the aperture value to reach the specified value from the initial value at the time the specified value is accepted using the first method, and determines the number of frames included between the initial value and the specified value based on the required time.

17. A method for operating a lens unit comprising an aperture whose aperture value can be changed and a processor, wherein the methods for controlling the aperture include a first method for controlling the aperture in response to an instruction from an imaging device, and a second method for controlling the aperture without receiving an instruction from the imaging device, and wherein the processor receives a designated value for the aperture value, and if the designated value is not included in a predetermined group of values, controls the aperture using the second method.

18. A program for operating a lens unit comprising an aperture whose aperture value can be changed and a processor, the program including, as methods for controlling the aperture, a first method for controlling the aperture in response to an instruction from an imaging device, and a second method for controlling the aperture without receiving an instruction from the imaging device, the program receiving a designated value for the aperture value, and causing the processor to execute processing to control the aperture in the second method if the designated value is not included in a predetermined group of values.

Images