Imaging apparatus, display control method, and program

Abstract

To notify a user of the influence of camera shake during still image exposure.SOLUTION: An imaging apparatus has: imaging means; shake detection means; generation means that generates shake information in still image exposure performed by the imaging means on the basis of a result of detection performed by the shake detection means during the still image exposure performed by the imaging means; and control means that displays, on a display, the shake information generated by the generation means. When the time of still image exposure when obtaining an image in which camera shake is corrected by using shake correction means is a first exposure time, the shake information is displayed on the display, and when the time of still image exposure is a second exposure time shorter than the first exposure time, the shake information is not displayed on the display.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to display control of an imaging device that performs blur correction during imaging. [Background technology]

[0002] In recent years, as imaging devices have become more sophisticated, many imaging devices and photographic lenses are equipped with image blur correction mechanisms. Image blur correction mechanisms enable users to reduce the effects of camera shake on captured images when holding an imaging device in their hands. Known image blur correction mechanisms used in imaging devices include a method that corrects blur by moving a portion of the lens in the photographic optical system in a direction perpendicular to the optical axis, and a method that corrects blur by moving the image sensor in the camera body in a direction perpendicular to the optical axis. A combination of these two methods is also known, which corrects blur by moving both a portion of the lens in the photographic optical system and the image sensor.

[0003] In recent years, there has been an increase in opportunities to check the composition by looking at the image displayed on the display unit without using the optical viewfinder before taking a photo, and opportunities to take long-exposure still images while handheld due to improvements in the performance of image stabilization mechanisms. However, when checking the composition by looking at the image displayed on the display unit without using the optical viewfinder, it is not possible to obtain an image during the still image exposure (shooting), and therefore it becomes impossible to check the state of the subject or camera during long-exposure shooting for a long period of time.

[0004] To address the problem of the subject image becoming invisible during shooting as described above, there is a technology disclosed in Patent Document 1 that notifies the user of the camera shake state during exposure by displaying the camera movement on the viewfinder. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-82719 Summary of the Invention [Problem to be solved by the invention]

[0006] However, when camera movement relative to a certain reference position is displayed on the viewfinder as in Patent Document 1, there is a problem in that it is not clear to what extent the camera movement (i.e., camera shake) will affect the captured image. For example, even if the same camera shake occurs, it is not possible to inform the user of the extent to which the captured image will be affected when the shooting conditions are different, such as when the focal length is different or the image height of the main subject is high.

[0007] The present invention has been made in view of the above-mentioned problems, and has as its object to notify a user of the influence of camera shake during exposure of a still image. [Means for solving the problem]

[0008] In order to achieve the above object, the imaging device of the present invention comprises an imaging means, a blur detection means, a generation means for generating blur information during still image exposure of the imaging means based on a detection result of the blur detection means during still image exposure of the imaging means, and a control means for displaying the blur information generated by the generation means on a display unit, wherein the blur information is displayed on the display unit when a still image exposure time when an image in which image blur has been corrected using a blur correction means is a first exposure time, and is not displayed on the display unit when the still image exposure time is a second exposure time shorter than the first exposure time. [Effects of the Invention]

[0009] According to the present invention, it is possible to notify the user of the effects of camera shake during exposure of a still image. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a diagram illustrating an imaging device according to a first embodiment of the present invention. [Figure 2]3A to 3C are diagrams illustrating blur information display on a display unit according to the first embodiment of the present invention. [Figure 3] FIG. 3 is a flowchart showing operations relating to photography according to the first embodiment of the present invention. [Figure 4] 10A and 10B are diagrams illustrating blur information display on a display unit according to a second embodiment of the present invention. [Figure 5] 10A and 10B are diagrams illustrating blur information display on a display unit according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] [First embodiment] A first embodiment of the present invention will be described below with reference to Fig. 1 to Fig. 3. Fig. 1 is a diagram illustrating an imaging device according to this embodiment, with Fig. 1(a) being a central cross-sectional view of the imaging device and Fig. 1(b) being a block diagram showing the electrical configuration of the imaging device. In Fig. 1(a) and Fig. 1(b), the same reference numerals are assigned to the same parts.

[0012] 1 has a camera body 1 and a lens barrel 2 attached to the camera body 1. In this embodiment, a so-called interchangeable lens camera in which the camera body 1 and the lens barrel 2 are each provided so as to be detachable will be described, but an imaging device in which the camera body 1 and the lens barrel 2 are integrated may also be used.

[0013] In FIG. 1, 3 denotes a photographic optical system consisting of multiple lenses mounted in a lens barrel 2, 4 denotes the optical axis of the photographic optical system 3, 5 denotes a camera system control unit, 6 denotes an image sensor, 7 denotes an image processing unit, and 8 denotes a memory. 3a denotes a blur correction lens in the photographic optical system 3 that corrects blur, 5a denotes a focus control unit in the camera system control unit 5, and 5b denotes a display blur information calculation unit in the camera system control unit 5. 9 denotes a display unit that displays live view images and photographed images, with 9a representing a rear display unit such as an LCD mounted on the rear of the camera body 1 and 9b representing an in-finder display unit mounted in the viewfinder of the camera body 1. The rear display unit 9a may be a touch panel that serves as both a display unit and an operation unit. 10 denotes an operation detection unit that detects signals from an operation unit including a shutter release button (not shown). Reference numeral 11 denotes a camera-side shake detection unit provided in camera body 1 that detects the movement of camera body 1 using an accelerometer, gyro sensor, etc., and 12 denotes a camera-side shake correction unit provided in camera body 1. Camera-side shake correction unit 12 has a drive mechanism such as a motor that moves image sensor 6 in a direction perpendicular to imaging optical axis 4.

[0014] Additionally, reference numeral 13 denotes electrical contacts that allow communication between camera body 1 and lens barrel 2, and 14 denotes a lens system control unit provided in lens barrel 2. Reference numeral 15 denotes a lens-side shake detection unit provided in lens barrel 2 that detects the movement of lens barrel 2 using an accelerometer, gyro sensor, or the like, and 16 denotes a lens drive unit that drives the focus lens that adjusts the focus and blur correction lens 3a that performs blur correction. Reference numeral 16a denotes a lens-side shake correction unit that has a drive mechanism such as a motor that moves blur correction lens 3a in a direction perpendicular to imaging optical axis 4.

[0015] The image processing unit 7 has an internal A / D converter, white balance adjustment circuit, gamma correction circuit, interpolation calculation circuit, etc., and can generate images for recording. The image processing unit 7 also has a color interpolation processing unit that performs color interpolation (demosaicing) processing on the Bayer array signal to generate a color image. The image processing unit 7 also compresses images, videos, audio, etc. using a predetermined method.

[0016] The memory 8 stores the image output from the image processing unit 7 and outputs the stored image to the display unit 9 for display.

[0017] The camera system control unit 5 controls each part of the camera body 1, and also communicates with the lens system control unit 14 to control each part of the lens barrel 2. For example, when the operation detection unit 10 detects that a shutter release button (not shown) has been pressed, the camera system control unit 5 controls the drive of the image sensor 6, the operation of the image processing unit 7, compression processing, etc. Furthermore, the camera system control unit 5 controls the state of each segment of the display unit 9 (display control) in order to display information on the display unit 9.

[0018] Camera system controller 5 is also connected to image processor 7, which determines appropriate focus and aperture positions based on signals from image sensor 6. Camera system controller 5 issues commands to lens system controller 14 via electrical contacts 13, which in turn controls the focus lens and aperture included in photographic optical system 3. The method for determining the focus and aperture positions is not particularly limited, and any known method may be used; for example, the focus position may be determined using a phase difference detection method or a contrast method. Furthermore, in a shake correction mode, camera system controller 5 controls camera-side shake correction unit 12 based on signals obtained from camera-side shake detection unit 11, and similarly controls lens shake correction unit 16a based on signals obtained from lens-side shake detection unit 15.

[0019] An example of a specific method for controlling blur correction will be described below. First, camera system control unit 5 and lens system control unit 14 acquire camera shake signals detected by camera-side shake detection unit 11 and lens-side shake detection unit 15, respectively. Based on the acquired results, camera system control unit 5 and lens system control unit 14 calculate the drive amounts for image sensor 6 and blur correction lens 3a, respectively, to correct image blur. The calculated drive amounts are then sent as command values ​​to camera-side shake correction unit 12 and lens-side shake correction unit 16a, which drive image sensor 6 and blur correction lens 3a, respectively. The method for controlling blur correction is not limited to this; either camera system control unit 5 or lens system control unit 14 may take the lead in calculating the drive amounts for each blur correction component (blur correction lens 3 and image sensor 6).

[0020] Furthermore, the camera system control unit 5 and the lens system control unit 14 control the various components of the camera body 1 and the lens barrel 2 in response to user operations on operation units (not shown) provided on the camera body 1 and the lens barrel 2. This makes it possible to capture still images and videos.

[0021] Next, blur information display on the viewfinder display 9b in this embodiment will be described using FIG. 2. Hereinafter, still image exposure, which is exposure for obtaining a still image, will be simply referred to as exposure, and still image exposure, still image exposure time, and still image pre-exposure will be referred to as exposure time, exposure time, and pre-exposure. FIGS. 2(a) to 2(e) show the subject image and blur information displayed on the viewfinder display 9b before and during exposure of the image sensor 6. The blur information display described using FIG. 2 may be displayed not only on the viewfinder display 9b but also on the rear display 9a. The display area of ​​the viewfinder display 9b is larger than that of an image 21a (described later). For example, when an image 21c is superimposed on the image 21a, the entire images 21a and 21c can be displayed.

[0022] In this embodiment, an image during exposure, estimated from the detection results of camera-side shake detection unit 11, is superimposed as blur information on a live view image taken immediately before exposure of image sensor 6 begins. This makes it possible to notify the user of the degree of blur that has occurred since exposure began. Below, the display on viewfinder display unit 9b is explained in chronological order. Note that while a live view image taken immediately before exposure begins is preferable as the image displayed during exposure, any live view image taken immediately before exposure can be used as long as it is within a predetermined time before exposure begins.

[0023] In the following explanation, we will describe a method of calculating the blur information for display using the detection results of camera-side blur detection unit 11, but the blur detection unit used is not limited to this. For example, it is possible to use lens-side blur detection unit 15, or to use both camera-side blur detection unit 11 and lens-side blur detection unit 15.

[0024] FIG. 2(a) shows a state in which a so-called live view image is displayed on the viewfinder display 9b before the image sensor 6 is exposed. The live view image is the image the user sees while looking through the viewfinder display 9b to determine the angle of view. It displays the image captured by the image sensor 6 in near real time during non-photography (live view) mode. In FIG. 2(a), 21a represents the image displayed as the live view image, 22a represents the subject, 23 represents the AF frame, and 24 represents the edge of the drive range of the image stabilizer mechanism (described later). The AF frame 23 represents a frame through which the user selects the position within the image plane at which to focus. In so-called autofocus mode, the amount of focus lens drive relative to the subject in the AF frame is determined, and the focus lens is automatically driven. Therefore, the user will often look closely at the area around the AF frame 23 on the viewfinder display 9b. In other words, the AF frame 23 can be considered the user's point of focus.

[0025] 2(b) shows the state of in-viewfinder display 9b when the user fully presses a shutter release button (not shown) or the like, starting exposure of image sensor 6. When camera-side shake detection unit 15 detects a user's hand shake, display-use blur information calculation unit 5b processes pre-exposure live-view image 21a in accordance with the output of camera-side shake detection unit 15, and displays the processed image as blur information superimposed on the pre-exposure live-view image. 21b represents the image generated by display-use blur information calculation unit 5b in accordance with the output of camera-side shake detection unit 15, and 22b represents the subject in 21b.

[0026] Specifically, display blur information calculation unit 5b creates a live view image during an expected exposure based on blur information such as the angular velocity and acceleration of camera body 1 obtained by camera-side shake detection unit 15, the shooting conditions, and live view image 21a immediately before the start of exposure. The shooting conditions here refer to the focal length determined by shooting optical system 3, the subject distance determined by the size and distance to the subject, image magnification, and other factors, and the amount of blur on image sensor 6 varies depending on these shooting conditions. In other words, because the display blur information differs, display blur information calculation unit 5b calculates the blur information based on these. In particular, when calculating blur information, the above-mentioned shooting conditions are necessary to calculate the amount of blur in the so-called shift direction, in which camera body 1 moves relative to the subject in a direction perpendicular to the optical axis. Therefore, display blur information calculation unit 5b calculates the display blur information based on the above-mentioned shooting conditions.

[0027] In Figure 2(b), the user moves camera body 1 toward the upper right toward the subject, causing the superimposed image to be displayed at a position to the upper right of the pre-exposure image in Figure 2(a). This indicates that camera body 1 experiences pitch and yaw shake, with the axis perpendicular to the optical axis 4 as the center of rotation, as well as shift shake, which is perpendicular to the optical axis 4. Hereinafter, when the subject or live view image moves parallel to the screen of viewfinder display 9b, this will be referred to as movement in the pitch, yaw, or shift directions. In this way, by generating and superimposing an image during exposure (blur information) estimated from the current detection results of the blur detection unit while keeping the pre-exposure live view image displayed, the user can determine the extent of camera shake. By viewing the blur information shown in Figure 2(b), the user can hold the camera with an awareness of camera shake, resulting in images with less camera shake.

[0028] Unlike the case of Figure 2(b), Figure 2(c) shows an image containing a camera shake component in the rotational direction (so-called roll direction) around an axis parallel to the optical axis. Hereinafter, when a subject or image moves in a direction that rotates relative to the screen of viewfinder display 9b, it will be referred to as movement in the roll direction. Reference numeral 21c denotes an image generated by display blur information calculation unit 5b in accordance with the output of camera shake detection unit 15, and reference numeral 22c denotes the subject in 21c. In Figure 2(c), an image during exposure, in which camera body 1 is assumed to have rotated around an axis parallel to the optical axis, is displayed on viewfinder display 9b with the user's gaze point, i.e., AF frame 23, as the center of rotation.

[0029] The advantages of displaying the image with the AF frame 23 as the center of rotation as described above will be explained using Figures 2(d) and 2(e). Like Figure 2(c), Figures 2(d) and 2(e) show displayed images containing a blur component in the rotational direction about an axis parallel to the optical axis. However, unlike Figure 2(c), they show a case in which the AF frame 25 is set at a position higher than the center of the screen. Figure 2(d) shows the pre-exposure live view image 21a rotated around the center of the image, while Figure 2(e) shows the image rotated around the AF frame 25.

[0030] The images in Figures 2(d) and (e) have a higher AF frame 25, i.e., a higher image height of the subject, compared to the images in Figures 2(a) to (c). Therefore, when roll blur is detected, the image in Figure 2(d) is more distorted than the image in Figure 2(e). A user viewing an image like Figure 2(d) may perceive blur in the pitch, yaw, and shift directions in addition to roll blur, which could lead to further blurring of the image when the user repositions the camera body 1. On the other hand, by rotating and displaying the live view image around the AF frame 25, which is likely to be the focus of the user's gaze, as in Figure 2(e), the user can easily recognize that the camera body 1 is moving in the roll direction. Therefore, as mentioned above, the intended suppression of camera shake is less likely to result in increased camera shake.

[0031] Next, we will explain the drivable range end 24 of the blur correction mechanism. The blur correction unit performs blur correction by mechanically driving the blur correction lens 3a or the image sensor 6, so the drivable range is limited. The drivable range (area) varies depending on the lens barrel 2 and the camera body 1, and the shape of the drivable range varies. FIG. 2 specifically illustrates a rectangular drivable range. In FIG. 2, 24 represents the range within which the blur correction mechanism can move immediately before exposure begins. This position is determined at the start of exposure and does not change until the end of exposure. Therefore, the position of the drivable range end 24 determined in FIG. 2(a), immediately before exposure begins, does not change even in the states of FIGS. 2(b) to 2(e). Furthermore, the drivable range end 24 indicates the extent to which the blur correction mechanism can correct camera shake. If the edge of the image calculated by the display blur information calculation unit 5b is inside the drivable range end 24 of the correction mechanism, the blur correction mechanism will not be able to sufficiently correct the blur. In both Figures 2(b) and 2(c), the edge of the image calculated by the display blur information calculation unit 5b is outside the drive range edge 24 of the correction mechanism, so it can be seen that the camera shake is small enough to be corrected by the blur correction mechanism.

[0032] In this way, by simultaneously viewing the display blur information and the drive range end 24 of the blur correction mechanism, it is possible to know the degree of camera shake that can be corrected.

[0033] Furthermore, in addition to displaying the drivable range of the shake correction mechanism, if the drivable range is exceeded, that is, if the shake correction function is no longer able to sufficiently correct the shake, a warning may be given by display or sound to notify whether shake correction is possible or not.

[0034] Furthermore, as a display method, the display blur information calculation unit 5b may perform control so as not to display any movement outside of a predetermined frequency band known as the frequency band of camera shake. For example, a method may be adopted in which movement of approximately 0.1 Hz to 10 Hz is displayed as display blur information, and blur information in other frequency bands is removed using a filter or the like so as not to be displayed. This stabilizes the image displayed on the viewfinder display unit 9b, making it easier for the user to view the image. Specifically, a method may be adopted in which a low-pass filter that passes signals of 10 Hz or less or a band-pass filter that passes signals of 0.1 Hz to 10 Hz is applied.

[0035] Furthermore, the display blur information may be displayed in an exaggerated manner compared to the actual blur. For example, the display blur information calculation unit 5b may multiply the actual amount of blur by a certain percentage to generate and display an exaggerated blurred image for display. By doing so, the image displayed on the viewfinder display unit 9b may appear to be more blurred than it actually is, allowing the user to take measures such as re-holding the camera to reduce camera shake, and as a result, an image with less camera shake can be obtained.

[0036] As described above, by calculating the display blur information based on the output of the blur detection unit, the position of the AF frame, and the shooting conditions, and then displaying the results on the display unit, it is possible to notify the user of the current effects of camera shake even during exposure.The user can also know during exposure how much correction the blur correction unit is making, and at what point correction will no longer be possible.

[0037] Next, the operations related to photography in this embodiment will be described with reference to Fig. 3. Fig. 3 is a flowchart of the operations related to photography, which start when the power of the camera body 1 is turned on. Note that the flowchart in Fig. 3 describes only a portion of the operations related to photography in order to explain the operations related to the display of blur information, and well-known operations related to photography may be combined as appropriate.

[0038] When the camera body 1 is powered on, in step S301 the camera system control unit 5 displays a live view image on the rear display unit 9a or the viewfinder display unit 9b. The camera system control unit 5 then determines whether or not the user has selected an AF frame using an operation unit (not shown). If the user has selected an AF frame, the process proceeds to step S302; otherwise, step S301 is repeated until an AF frame is selected.

[0039] In step S302, when an AF command is issued by half-pressing a shutter release button (not shown), the camera system control unit 5 performs focus control using the focus control unit 5a. Then, communication is established with the lens system control unit 14 via the electrical contacts 13, and the lens drive unit 16 drives the focus lens (not shown), and the process proceeds to step S303. During this time, a live view image continues to be displayed on the rear display unit 9a or the viewfinder display unit 9b.

[0040] In step S303, the camera system control unit 5 determines whether or not the user has issued an exposure start instruction by fully pressing a shutter release button (not shown), etc. If the user has issued an exposure start instruction, the process proceeds to step S304; if not, the process returns to step S301.

[0041] In step S304, camera system control unit 5 starts exposure by controlling a shutter (not shown) and image sensor 6. Then, display blur information calculation unit 5b calculates display blur information based on the blur information detected by camera-side blur detection unit 11, the shooting conditions determined by the shooting optical system 3 and the like, and live view image 21a immediately before exposure, and the flow proceeds to step S305.

[0042] In step S305, the camera system control unit 5 displays the live view image 21a immediately before exposure, which serves as the basis for the blur information for display, on the rear display unit 9a or the in-finder display unit 9b, superimposed on the blur information for display, and then proceeds to step S306.

[0043] In step S306, the camera system control unit 5 determines whether the set exposure time has elapsed, and if so, proceeds to step S307, otherwise returns to step S304. Until the exposure time has elapsed, the calculation of the display blur information and the updating of the image display are repeated at a predetermined cycle.

[0044] In step S307, the camera system control unit 5 performs exposure end processing, causes the rear display unit 9a or the in-finder display unit 9b to display a live view image again, and proceeds to step S308.

[0045] In step S308, the camera system control unit 5 determines whether the power to the camera body 1 has been turned off by an operation unit including a power button (not shown), and if the power has been turned off, ends the flow; if not, returns to step S301.

[0046] As explained above, it is possible to notify the user of the current effects of camera shake even during exposures with long exposure times. This allows the user to know during exposure how much correction the shake correction unit is making, and at what point correction will no longer be possible.

[0047] Second Embodiment Hereinafter, a second embodiment of the present invention will be described with reference to FIG.

[0048] The second embodiment differs from the first embodiment in the method of displaying blur information generated by the display blur information calculation unit 5b. As the other configurations are basically the same as those of the first embodiment, only the differences will be described in detail.

[0049] 4A to 4C are diagrams illustrating the display of blur information on the viewfinder display 9b in this embodiment, and show the subject image and blur information displayed on the viewfinder display 9b before and during exposure of the image sensor 6. In this embodiment, the blur information may also be displayed on the rear display 9a.

[0050] In this embodiment, the images generated by the display blur information calculation unit 5b are displayed as blur information superimposed one after another on the live view image before the start of exposure, thereby making it possible to notify the user of the degree of blurring from the start of exposure in chronological order.

[0051] The display in the viewfinder display section 9b will be explained in chronological order below. Note that the method of calculating blur information in this embodiment is the same as in the first embodiment, and the display area of ​​the viewfinder display section 9b is also the same as in the first embodiment.

[0052] 2(a), Fig. 4(a) shows a state in which a so-called live view image is displayed on the viewfinder display section 9b before exposure of the image sensor 6. Reference numeral 41a denotes the image displayed as the live view image, 42a denotes the subject, 43 denotes the AF frame, and 44 denotes the end of the drivable range of the image blur correction mechanism.

[0053] 4(b) shows the state of in-viewfinder display 9b when the user fully presses a shutter release button (not shown) or the like, starting exposure of image sensor 6. When camera-side shake detection unit 15 detects a user's hand shake, display-use blur information calculation unit 5b processes pre-exposure live-view image 41a in accordance with the output of camera-side shake detection unit 15, and displays the processed image as blur information superimposed on the pre-exposure live-view image. 41b represents the image generated by display-use blur information calculation unit 5b in accordance with the output of camera-side shake detection unit 15, and 42b represents the subject in 41b.

[0054] FIG. 4(c) shows an image obtained when camera shake has occurred in the direction of rotation (i.e., roll direction) around an axis parallel to the optical axis from the state shown in FIG. 4(b). Reference numeral 41c denotes an image generated by display blur information calculation unit 5b in accordance with the output of camera shake detection unit 15, and reference numeral 42c denotes the subject in 41c. In FIG. 4(c), an image during exposure, in which camera body 1 is assumed to have rotated around an axis parallel to the optical axis, is displayed on viewfinder display unit 9b with the user's gaze point, i.e., AF frame 23, as the center of rotation. Furthermore, in FIG. 4(c), new image 41c is superimposed on the state shown in FIG. 4(b). By sequentially superimposing the assumed images during exposure, the user is notified of the history of camera shake during exposure as blur information.

[0055] In this way, by generating and sequentially superimposing an image during exposure (blur information) estimated from the current detection results of the blur detection unit while displaying the pre-exposure live view image, the user can know the extent of camera shake. By viewing the blur information shown in Figures 4(b) and 4(c), the user can hold the camera while being aware of camera shake, resulting in an image with less camera shake.

[0056] Third Embodiment Hereinafter, a third embodiment of the present invention will be described with reference to FIG.

[0057] The third embodiment differs from the first embodiment in the display content of the blur information generated by the display blur information calculation unit 5b. As the other configurations are basically the same as those of the first embodiment, only the differences will be described in detail.

[0058] 5A to 5E are diagrams illustrating the display of blur information on the viewfinder display 9b in this embodiment, and show the subject image and blur information displayed on the viewfinder display 9b before and during exposure of the image sensor 6. In this embodiment, the blur information may also be displayed on the rear display 9a.

[0059] In this embodiment, a blur information display marker is displayed at the position of the AF frame of the live view image immediately before the start of exposure of the image sensor 6, and an estimated marker is calculated from the detection results of camera-side shake detection unit 11 and displayed as blur information superimposed on the marker before the start of exposure. This makes it possible to notify the user of the degree of blur that has occurred since the start of exposure. In this case, the position of the AF frame that is the user's point of gaze is used as the display position of the blur information display marker.

[0060] The display in the viewfinder display section 9b will be explained in chronological order below. Note that the method of calculating blur information in this embodiment is the same as in the first embodiment.

[0061] 5(a) shows a so-called live view image and a blur information display marker displayed on the viewfinder display section 9b at the position of the AF frame where the user is looking before exposure of the image sensor 6. Reference numeral 51 denotes the image displayed as the live view image, 52 denotes the subject, 53 denotes the AF frame, 54 denotes the edge of the drivable range of the blur correction mechanism, and 55a denotes the blur information display marker.

[0062] When the camera body 1 is moved to change the framing before exposure, the position of the blur information display marker 55a displayed in the viewfinder display section 9b does not move, but remains superimposed on the AF frame 53.

[0063] FIG. 5(b) shows the state of viewfinder display 9b when the user fully presses a shutter release button (not shown) or the like and exposure of image sensor 6 begins. Since the live view image disappears once exposure of image sensor 6 begins, only the blur information display marker is displayed. When camera shake detection unit 15 detects the user's hand movement, display blur information calculation unit 5b calculates the position of the blur information display marker based on the output and displays it as blur information, superimposed on the pre-exposure blur information display marker. Here, 56 indicates an area where no image is displayed, and 55b indicates the blur information display marker during exposure. In FIG. 5(b), when exposure of image sensor 6 begins, pre-exposure blur information display marker 55a is displayed as a dashed line, which is used as a reference for the user to check the blur information.

[0064] Specifically, display blur information calculation unit 5b calculates an expected blur information display marker from blur information such as the angular velocity and acceleration of camera body 1 and the shooting conditions obtained by camera-side blur detection unit 15. Then, the calculated blur information display marker is displayed superimposed on the blur information display marker immediately before the start of exposure.

[0065] 5(b), the user has moved camera body 1 in an upper right direction toward the subject, and blur information display marker 55b is displayed in a position to the upper right of blur information display marker 55a. In other words, blur information display marker 55b during exposure is displayed in a position that has moved relative to blur information display marker 55a immediately before exposure, in accordance with the movement of camera body 1 during exposure.

[0066] By viewing blur information such as that shown in Figure 5(b), the user can hold the camera while being aware of camera shake, resulting in an image with less camera shake.

[0067] Unlike the case of Figure 5(b), Figure 5(c) shows the display content of viewfinder display unit 9b when there is a blur component in the rotation direction around an axis parallel to the optical axis (the so-called roll direction). 55c shows a blur information display marker in a state rotated around an axis parallel to the optical axis. Blur information display marker 55c represents the blur component in the rotation direction around an axis parallel to the optical axis (the so-called roll direction) by tilting it with AF frame 53 as the center of rotation.

[0068] As described above, in this embodiment, by displaying a blur information display marker that indicates the state of camera shake during exposure, the user can accurately know the camera shake in the yaw, pitch, and shift directions and the camera shake in the roll direction during exposure.

[0069] Furthermore, as a display method in this embodiment, the length of the cross section (hereinafter referred to as the arm) of the blur information display marker may be changed depending on the position (image height) of the AF frame. A characteristic of camera shake in the roll direction is that the higher the image height of the image sensor 6, the more noticeable the effects of camera shake. Therefore, by making the arm length longer the higher the image height of the AF frame, i.e., the blur information display marker, the easier it is for the user to recognize camera shake in the roll direction.

[0070] As described above, by calculating the display blur information based on the output of the blur detection unit, the position of the AF frame, and the shooting conditions, and then displaying the results on the display unit, it is possible to notify the user of the current effects of camera shake even during exposure.The user can also know during exposure how much correction the blur correction unit is making, and at what point correction will no longer be possible.

[0071] In the above three embodiments, examples have been described in which the user selects the AF frame, but the camera system control unit 5 may select the AF frame based on a live view image. In addition to selecting an AF frame, the user may be allowed to select any area within the imaging area according to their photographic intent.

[0072] Furthermore, when the blur information is displayed in a superimposed manner, the blur information may be displayed in a color different from that of the reference image, or may be displayed in a semi-transparent state.

[0073] Furthermore, in the above three embodiments, examples have been described in which blur information is displayed regardless of the exposure time during exposure. However, it is generally believed that the impact of camera shake on a captured image is small when the exposure time is shorter than the reciprocal of the focal length. Furthermore, when the exposure time is short, even if blur information is displayed, the display time is short, making it difficult for the user to grasp the state of camera shake. Therefore, it is also possible to display blur information during exposure only when the exposure time is longer than a predetermined time. The predetermined time may be set to a fixed value, such as one second, that allows the user to grasp the state of camera shake, or it may be changed according to the focal length.

[0074] Furthermore, when an image is displayed superimposed on a live view image taken immediately before the start of exposure, reflecting camera shake that occurred during exposure, as in the first and second embodiments, there is a risk that the user may have difficulty recognizing the extent of camera shake if the entire image is displayed. Therefore, it is possible to extract and display only a predetermined range from the selected AF frame from the image, or only the subject that exists in the selected AF frame.

[0075] Furthermore, the user may be allowed to select which of the blur information display methods in the first to third embodiments to use.

[0076] Furthermore, instead of displaying the shake information on the display unit 9 of the camera body 1, the shake information may be displayed on the display unit of an external device (for example, a smartphone or tablet terminal) connected to the camera body 1. In this case, the shake information may be transmitted to the external device from a communication unit provided in the camera body 1 via a wired or wireless connection. [Explanation of symbols]

[0077] 1 camera body 5 Camera system control unit 9 Display section 11 Camera side shake detection unit

Claims

[Claim 1] An imaging means; a blur detection means; a generating means for generating blur information during a still image exposure of the imaging means based on a detection result of the blur detection means during a still image exposure of the imaging means; a control unit that causes the blur information generated by the generation unit to be displayed on a display unit, the blur information is displayed on the display unit when blur is detected by the blur detection unit if a still image exposure time when an image in which image blur has been corrected using a blur correction unit is a first exposure time, and the blur information is not displayed on the display unit if the still image exposure time is a second exposure time that is shorter than the first exposure time.

Images