JP7110078B2 - Imaging device, imaging method - Google Patents

Description

The present invention relates to an imaging apparatus and an imaging method for generating a depth-stacked image by stacking a plurality of pieces of imaging data acquired while moving a focus position.

In order to take a photograph in which the entire range of the main subject is in focus, the aperture is generally narrowed down to increase the depth of field. However, there are mechanical and optical limits to how much you can stop down, and it is often difficult to obtain a sufficient depth of field, especially in macro areas, even if you stop down to the maximum.

Therefore, conventionally, there has been proposed an imaging apparatus that acquires a plurality of pieces of image data while moving the focus position, and performs focus stacking on the acquired plurality of pieces of image data to generate a focus stacking image.

Using the focus stacking function makes it possible to sharply depict only the main subject without having to stop the aperture extremely, even in telephoto or macro photography where it is usually difficult to obtain a deep depth of field. Further, since it is not necessary to narrow down the aperture extremely, it is possible to secure the amount of light necessary for photographing, and not only is it possible to use a high-speed shutter, but also the S/N ratio is high, which makes it possible to improve the image quality. can. Furthermore, it is possible to prevent deterioration of resolution due to the diffraction phenomenon when the aperture is too narrow, and it is possible to set the aperture value at which the highest resolution is obtained and shoot. Alternatively, if you open the aperture and blur the background strongly to focus stacking, you can take a photo with a strong sense of depth while the main subject is sharp and the background is strongly blurred.

As an example of live view display when performing such focus stacking photography, Japanese Patent Application Laid-Open No. 2001-298755 discloses that images of a plurality of subframes with different focus positions are acquired, and the plurality of subframe images are focus-stacked. , a technique for generating and displaying a live view image of one frame.

Japanese Patent Application Laid-Open No. 2001-298755

By the way, live view images are usually displayed at 30 to 60 fps. For this reason, when obtaining, for example, 6 sub-frame images to generate a one-frame live view image with focus stacking, it is necessary to obtain 180 to 360 sub-frame images per second. However, for example, since the taking lens attached to a single-lens reflex camera is large, it is practically difficult to change the focal position 180 to 360 times per second. It is not realistic to apply Therefore, even when performing focus stacking photography, the single-lens reflex camera has no choice but to display a normal live view image instead of a focus stacking live view image.

On the other hand, lenses commonly used in interchangeable-lens cameras change their effective focal length on the short-distance side in order to maximize the image magnification in close-distance photography, so that focusing is possible at closer distances. may be configured to When the effective focal length changes, the angle of view also changes. Therefore, when focus stacking photography is performed on the short-distance side, a plurality of images with different angles of view are subjected to focus stacking processing. At this time, in order to generate a focus stacking image according to the image with the narrowest angle of view, a focus stacking image with a narrower angle of view than the normal live view image before shooting is generated. There can be a problem of stuttering.

Moreover, the amount of deviation in the angle of view between the live view image and the focus stacking image not only varies depending on the shooting lens, but also varies depending on the focus movement range and direction from the shooting start point to the shooting end point in focus stacking shooting. are also different. That is, the amount of deviation of the angle of view is not uniquely determined according to the photographing lens, but depends on the user's aim and method of photographing, i.e., in which photographing distance range the user intends to perform focus stacking photographing. It will be. In addition, in focus stacking photography in which a plurality of images are acquired, since the total photography time is long, blurring occurs in each image when hand-held photography is performed. For this reason, the common portion of a plurality of acquired images becomes smaller, and a depth-stacked image with a narrower angle of view is generated. The amount of angular deviation increases.

As described above, the user cannot uniquely recognize the shooting angle of view for focus stacking in normal live view before shooting. When an image is captured, the user has to reset the camera settings so that a wider range is displayed in the live view image, and then recapture the image.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and is an imaging apparatus capable of uniquely confirming the angle of view of a focus stacking image generated by focus stacking photography as widely as possible before shooting. , to provide an imaging method.

An imaging apparatus according to an aspect of the present invention includes a photographing lens that forms an image of a subject and that has an effective focal length that changes according to a focus position; an imaging unit that captures the subject image and outputs imaged data; a live view display unit that displays a live view based on data; a focus stacking view angle range display unit that displays a view angle range of a focus stacking image on the live view; and a near point focus position and a far point in focus stacking photography. and a focus position determination unit for focus stacking that determines and outputs the focus position of the focus stacking, and in the main shooting of the focus stacking shooting, the focus position of the photographing lens is set between the near point focus position and the far point focus position. Based on the effective focal length when each of the plurality of imaging data is captured, and a composite angle-of-view adjusting unit that adjusts the angle of view of each of the plurality of imaging data; and a focus stacking that generates the depth-stacked image by performing focus stacking on the plurality of imaging data whose angles of view have been adjusted by the composite angle-of-view adjusting unit. , wherein the focus stacking angle of view range display unit changes according to a change in at least one of the information on the photographing lens, the output content of the focus stacking focus position determination unit, and the shooting distance. and updating the display of the view angle range of the depth stacking image based on the effective focal length when displaying the live view and the effective focal length when the focus position of the far point is set.

An imaging apparatus according to another aspect of the present invention includes a photographing lens that forms a subject image and whose effective focal length changes according to a focus position; an imaging unit that captures the subject image and outputs imaged data; a live view display unit for displaying a live view based on imaging data; a focus stacking view angle range display unit for displaying a view angle range of a focus stacking image on the live view; A maximum angle of view variation determination unit that determines the maximum angle of view variation within the movable range of the focus position, and a focus stacking unit that determines and outputs the near point focus position and the far point focus position in focus stacking photography. a focus position determination unit, and the image pickup unit while moving the focus position of the photographing lens between the near point focus position and the far point focus position by a predetermined amount in the main photographing of the focus stacking photographing. and an imaging control unit for repeatedly capturing images and outputting a plurality of imaging data, and adjusting the angle of view of each of the plurality of imaging data based on the effective focal length when each of the plurality of imaging data is captured. a composite angle of view adjusting unit; and a focus stacking unit configured to generate the focus stacking image by performing focus stacking of the plurality of image data whose angles of view have been adjusted by the composite angle of view adjusting unit, wherein the focus stacking angle of view The range display unit displays, on the live view, the angle of view range of the focus stacking image based on the maximum angle of view variation, and the combined angle of view adjustment unit adjusts the angle of view before actual photography of the focus stacking photography. The angle of view of each of the plurality of imaging data is adjusted based on the angle of view range of the focus stacking image displayed on the live view.

An imaging method according to still another aspect of the present invention includes an imaging step of imaging a subject image and outputting imaging data; a live view display step of displaying a live view based on the imaging data; on the live view; a focus stacking focus position determining step of determining and outputting a near point focus position and a far point focus position in focus stacking photography; and the focus stacking In the actual photographing of the photographing, the photographing step is repeated while moving the focus position of the photographing lens that forms the subject image by a predetermined amount between the near point focus position and the far point focus position. an image capturing control step of causing an image to be captured and outputting a plurality of image data; and adjusting the angle of view of each of the plurality of image data based on the effective focal length of the photographing lens when each of the plurality of image data is captured. a composite angle of view adjustment step; and a focus stacking step of generating the focus stacking image by focus stacking the plurality of image data whose angles of view have been adjusted by the composite angle of view adjustment step, wherein the focus stacking angle of view The range display step displays the effective focus when displaying the live view in accordance with a change in at least one of the information of the photographing lens, the output content of the focus stacking focus position determination step, and the photographing distance. The display of the view angle range of the focus stacking image is updated based on the distance and the effective focal length at the far point focus position.

An imaging method according to still another aspect of the present invention includes an imaging step of imaging a subject image and outputting imaging data, a live view display step of displaying a live view based on the imaging data, and an angle of view of a focus stacking image. a focus stacking view angle range display step of displaying the range on the live view; and a maximum view angle variation amount within the movable range of the focus position of the photographing lens based on the information of the photographing lens that forms the subject image. A step of determining the maximum angle of view variation to be determined; a step of determining and outputting a near point focus position and a far point focus position in focus stacking photography; Imaging control for repeating the imaging step while moving the focus position of the photographing lens between the near point focus position and the far point focus position by a predetermined amount, and outputting a plurality of image data. a synthetic angle of view adjustment step of adjusting the angle of view of each of the plurality of image data based on the effective focal length of the photographing lens when each of the plurality of image data is captured; and the synthetic angle of view adjustment. and a focus stacking step of generating the focus stacking image by stacking the plurality of pieces of imaging data whose angle of view has been adjusted by the step, wherein the focus stacking view angle range display step is set to the maximum view angle variation amount. the field angle range of the focus stacking image based on the focus stacking image is displayed on the live view; The angle of view of each of the plurality of imaging data is adjusted based on the angle of view range.

According to the image pickup apparatus and image pickup method of the present invention, it is possible to confirm the angle of view of a focus stacking image generated by focus stacking photography as widely and uniquely as possible before photographing.

1 is a block diagram showing the configuration of an imaging device according to Embodiment 1 of the present invention; FIG. FIG. 2 is a perspective view showing the appearance of the imaging apparatus according to the first embodiment from the back side; 4 is a diagram showing an example of change in effective focal length when the distance to the photographing object changes in the first embodiment; FIG. FIG. 4 is a diagram showing an example of change in image magnification when the distance to the object to be photographed is changed, in comparison with when the effective focal length is changed and when it is not changed in the first embodiment; FIG. 5 is a diagram showing how the angle of view changes according to the focus stacking direction and the focus position when focus stacking capturing is performed with changes in the effective focal length in the first embodiment; 4 is a flowchart showing main processing in the imaging apparatus of the first embodiment; 4 is a flowchart showing lens information acquisition processing in the first embodiment; 4 is a flow chart showing processing for depth stacking shooting interlocking setting in the first embodiment. 4 is a flowchart showing camera shake correction interlocking processing according to the first embodiment; A timing chart showing an operation example of camera shake correction with priority given to continuous shooting speed and an example of a captured image in the first embodiment. A timing chart showing an operation example of camera shake correction with priority given to camera shake correction and an example of a captured image in the first embodiment. 4 is a flowchart showing a first example of live view display processing for focus stacking photography according to the first embodiment; 9 is a flowchart showing a second example of live view display processing for focus stacking photography according to the first embodiment; 4 is a flowchart showing a first example of processing for specifying a focus stacking angle of view range in the first embodiment; 9 is a flowchart showing a second example of processing for specifying the focus stacking angle of view range in the first embodiment; 9 is a flowchart showing a third example of processing for specifying the focus stacking angle of view range in the first embodiment; 6 is a flowchart showing display update processing of the focus stacking angle of view range in the first embodiment; 4 is a flowchart showing digital teleconverter display processing in the first embodiment; 4 is a flowchart showing processing of still image shooting for focus stacking shooting in the first embodiment; 4 is a flowchart showing camera shake correction processing during continuous shooting according to the first embodiment; 4 is a flowchart showing focus movement processing in the first embodiment; 4 is a flowchart showing focus stacking processing in the first embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Embodiment 1]

1 to 22 show Embodiment 1 of the present invention, and FIG. 1 is a block diagram showing the configuration of an imaging device 1. FIG.

The imaging device 1 captures an image of a subject and generates imaging data, and is configured as a digital camera, for example. In particular, the imaging apparatus of this embodiment is configured as, for example, a single-lens camera (mirrorless single-lens camera, single-lens reflex camera, etc.), and includes a camera body 3, a photographic lens 2 detachable from the camera body 3, It has However, the imaging device 1 is not limited to a single-lens camera, and may be a so-called compact type camera, such as a digital video camera, a communication device with a photographing function, a microscope with a photographing function, an endoscope, a surveillance camera, or the like. It may be a device having various imaging functions.

The photographing lens 2 forms an image of a subject, and FIG. 1 particularly shows an example in which a camera shake correction function (Lens Image Stabilization (IS)) is provided in the lens.

That is, the photographing lens 2 includes a lens 21, an aperture 22, an image stabilization optical element 23, an image stabilization control section 24, an aperture control section 25, a lens control section 26, an image stabilization section 27, and an operation section 28. , and a communication control unit 29 .

The lens 21 is an optical system that forms a subject image, and is configured by combining one or more (generally, a plurality of) lenses. The lens 21 has an adjustable focus position, and includes, for example, a focus lens for adjusting the focus position.

The diaphragm 22 is an optical diaphragm that controls the passage range of the light flux passing through the lens 21 . When the aperture diameter of the diaphragm 22 is changed, the brightness of the subject image changes, and the degree of blur also changes.

The camera shake correction optical element 23 corrects blurring of the subject image due to camera shake by moving, for example, in a direction perpendicular to the optical axis of the lens 21 .

Although FIG. 1 schematically shows the lens 21, the diaphragm 22, and the image stabilization optical element 23 as separate bodies, the diaphragm 22 and the image stabilization optical element 23 are actually inside the lens 21. It does not matter if it is incorporated.

The camera shake correction control unit 24 controls and drives the camera shake correction optical element 23 so as to cancel the movement of the subject image due to camera shake detected by the camera shake detection unit 27 .

The aperture control section 25 changes the aperture diameter of the aperture 22 based on the command from the camera body 3 .

The lens control unit 26 adjusts the focus position of the taking lens 2 including the lens 21 based on a command from the camera body 3 .

A camera shake detection unit 27 includes an angular velocity sensor such as a gyro sensor, and detects camera shake occurring in the photographing lens 2 .

The operation unit 28 is for performing operations related to the photographing lens 2 . The operation unit 28 includes, for example, an IS switch for switching ON/OFF of the lens IS by the camera shake correction optical element 23 and the camera shake correction control unit 24 .

The communication control section 29 communicates with a later-described lens communication section 37 of the camera body 3 , receives commands from the camera body 3 , and transmits various information related to the photographic lens 2 to the camera body 3 .

The camera body 3 includes a mechanical shutter 30, an imaging unit 31, an A/D conversion unit 32, a memory 33, an image processing unit 34, an imaging drive control unit 35, a shutter control unit 36, and a lens communication unit 37. , camera shake detection unit 38 , exposure control unit 39 , AF processing unit 40 , nonvolatile memory 41 , external memory 42 , display unit 43 , operation unit 44 , power supply control unit 45 , and power supply unit 46 . , a flash unit 47 , and a system control unit 48 .

The mechanical shutter 30 controls the time for the light flux from the photographing lens 2 to reach the imaging section 31, and is configured as an optical shutter for running a shutter curtain having a light shielding function, for example.

The imaging unit 31 has an imaging device (image sensor) that captures a subject image and outputs an imaging signal (imaging data), and an image stabilization function (body IS) that moves the imaging device in a direction perpendicular to the optical axis of the imaging lens 2 (B-IS: Body Image Stabilization) In addition to the optical camera shake correction that moves the image pickup device by the mechanical configuration of the image pickup unit 31, the image processing unit 34 performs image stabilization as the body IS. There is electronic image stabilization that digitally processes data electronically.

Here, when the optical axis of the photographing lens 2 is the z-axis, and the two orthogonal axes of the imaging surface 31 perpendicular to the z-axis are the x-axis (horizontal axis) and the y-axis (vertical axis), the imaging unit of this embodiment As will be described later, the optical camera shake correction by 31 is based on angular shake around the x-axis (pitch direction), angular shake around the y-axis (yaw direction), and around the z-axis (roll direction). It is configured to be capable of correcting rotational shake, shift shake in the x-axis direction, and shift shake in the y-axis direction.

The A/D conversion section 32 converts the analog imaging signal output from the imaging section 31 into a digital imaging signal.

The memory 33 stores image data output from the A/D conversion unit 32, stores image data processed by the image processing unit 34, and is also used as a work memory for the system control unit 48. It's becoming

The image processing unit 34 reads the image data stored in the memory 33, performs various image processing on the image data, generates image data for display and image data for recording, and stores the generated image data in the memory. 33. Further, the image processing unit 34 functions as a digital teleconverter setting unit (digital teleconverter setting circuit) for enlarging the image by limiting the angle of view of the captured data based on a predetermined digital teleconverter magnification. ing.

The imaging drive control unit 35 controls pixel reset of the imaging device, exposure start (charge accumulation start), and exposure end (charge accumulation end by reading from pixels). By controlling the exposure start timing and the exposure end timing, it is possible to function as a so-called electronic shutter.

Further, the imaging drive control section 35 controls and drives the body IS of the imaging section 31 so as to cancel the movement of the subject image due to the camera shake detected by the camera shake detection section 38 .

The shutter control section 36 controls opening and closing of the mechanical shutter 30 . For example, the mechanical shutter 30 is open when shooting a live view image or when performing focus stacking photography with an electronic shutter (also called automatic focus stacking photography because a plurality of images are automatically captured). controlled to be maintained.

The exposure time of the image sensor is, for example, the start and end of exposure by the mechanical shutter 30, the start and end of exposure by the electronic shutter, the start of exposure by the electronic shutter and the end of exposure by the mechanical shutter 30 (first curtain and electronic shutter). called) and any combination of

The lens communication unit 37 communicates with the above-described communication control unit 29 of the photographing lens 2, and receives information of the photographing lens 2 (lens ID (lens type name, lens serial number, etc.), focal length, closest focus position, current focus position, etc.).

A camera shake detection unit 38 includes an angular velocity sensor such as a gyro sensor and an acceleration sensor for detecting parallel movement, and detects camera shake occurring in the camera body 3 .

Based on the imaging data stored in the memory 33, the exposure control unit 39 sets the exposure condition, specifically the exposure time (shutter speed), so that the subject image formed on the imaging device has appropriate brightness. , the aperture value of the aperture 22, the ISO sensitivity (amplification factor of the imaging signal), and the like.

The AF processing unit 40 performs AF (autofocus) processing, for example, based on imaging data, and generates a control signal for adjusting the focus position so that the target portion of the subject is in focus. This control signal is transmitted to the lens control section 26 via the system control section 48, the lens communication section 37, and the communication control section 29, and the focus lens in the lens 21 is driven and controlled by the lens control section 26.

The nonvolatile memory 41 is composed of, for example, a flash memory, and stores a processing program (a control program for the imaging device 1) executed by the system control unit 48, various data related to the imaging device 1, and setting values set by the user. It is a recording medium for nonvolatilely recording such as.

The external memory 42 is a recording medium for recording image data for recording that has been image-processed by the image processing unit 34 and stored in the memory 33 . Since the external memory 42 is composed of, for example, a memory card that can be attached to and detached from the camera body 3 , it does not have to be a configuration unique to the imaging apparatus 1 .

The display unit 43 is a display device that displays an image based on image data for display that has been image-processed by the image processing unit 34 and stored in the memory 33 . Here, the image is displayed during live view, image confirmation after still image shooting, playback of images stored in the external memory 42, and the like. Therefore, the display unit 43 is a live view display, and serves as a live view display unit that displays a live view based on the imaging data.

In addition, various information can be superimposed on the image on the display unit 43, and a display indicating the angle of view range of the depth stacking image as described later (a specific example is a frame for restricting the angle of view). superimposed. Therefore, the display unit 43 is a focus stacking view angle range display, and serves as a focus stacking view angle range display unit that displays the view angle range of the focus stacking image on the live view.

The operation unit 44 is for performing various operation inputs to the imaging device 1, and is configured by devices such as buttons, switches, and a touch panel, for example. The operation unit 44 includes a power button for turning on/off the power of the imaging device 1 and other operation buttons. Some examples of other operation buttons are described later with reference to FIG. When an operation is performed on the operation unit 44 , a signal corresponding to the content of the operation is output to the system control unit 48 .

The power control section 45 controls the power section 46 .

The power supply unit 46 supplies electric power to each unit in the imaging device 1 under the control of the power supply control unit 45 .

The flash unit 47 irradiates the subject with illumination light under the control of the system control unit 48 . Light emission of the flash unit 47 is appropriately performed as necessary also in focus stacking photography.

The system control section 48 controls each section within the camera body 3 , and transmits commands to the communication control section 29 via the lens communication section 37 to control each section within the photographing lens 2 . Therefore, the system control unit 48 serves as a control unit that controls the imaging apparatus 1 in a centralized manner. When the user performs an operation input from the operation unit 44, the system control unit 48 reads parameters necessary for processing from the nonvolatile memory 41 according to the processing program stored in the nonvolatile memory 41, and Executes various sequences.

The system control unit 48 also functions as a focus position determination unit for focus stacking (focus position determination circuit for focus stacking), and determines and outputs a near point focus position and a far point focus position in focus stacking photography.

Further, the system control unit 48 functions as an imaging control unit (imaging control circuit), and in the actual photography of focus stacking photography, transmits a command to the lens control unit 26 to set the focus position of the photographing lens 2 to the near point focus. A command is transmitted to the image pickup drive control unit 35 to cause the image pickup unit 31 to repeat image pickup and output a plurality of image data while moving the image pickup unit 31 between the position and the far point focus position by a predetermined amount.

Next, FIG. 2 is a perspective view showing the appearance of the imaging device 1 from the rear side.

The imaging apparatus 1 is configured by detachably connecting a photographing lens 2 and a camera body 3 using a lens mount or the like having an electrical contact.

A rear monitor 43 a that constitutes a display unit 43 is arranged on the rear surface of the camera body 3 . A touch panel that constitutes the operation unit 44 is provided on the rear monitor 43a. Furthermore, an electronic viewfinder (EVF) 43b that constitutes the display unit 43 is arranged above the rear monitor 43a (that is, FIG. 2 shows an example in which the imaging device 1 is a mirrorless single-lens camera). .

A release button 44a, a front dial 44b, a rear dial 44c, a shooting mode dial 44d, a moving image button 44j, and an enlargement button 44k are arranged on the upper surface of the camera body 3 on the right side of the electronic viewfinder 43b.

The release button 44a is a button for instructing the start of image capturing, and is, for example, a two-stage operation button having a 1st (first) release switch and a 2nd (second) release switch.

The front dial 44b and the rear dial 44c are used, for example, when adjusting various parameters according to the shooting mode.

The shooting mode dial 44d is used for selecting a shooting mode.

The moving image button 44j is used to issue an instruction to start shooting a moving image and an instruction to end shooting a moving image.

The magnify button 44k is used for magnifying and displaying an image.

A cross button 44e, an OK button 44f, an AF button 44g, and an information button 44h are arranged on the back of the camera body 3 on the right side of the back monitor 43a.

The cross-shaped button 44e is used for selecting menu items displayed on the rear monitor 43a.

The OK button 44f is used to confirm selection items of the menu displayed on the rear monitor 43a.

The AF button 44g selects AF methods such as constant AF, single AF (S-AF), continuous AF (C-AF), manual focus (MF), and combination of S-AF and MF (S-AF+MF). used for

The information button 44h is used to select whether or not to display information on the rear monitor 43a and/or the electronic viewfinder 43b, and to select information to be displayed.

Also, a focus stacking button 44i is provided at the upper right corner on the back side of the camera body 3 . The focus stacking button 44i is used for switching from the normal shooting mode to the focus stacking shooting mode, switching from the focus stacking shooting mode to the normal shooting mode, setting the focus stacking type in the focus stacking shooting mode, and the like. Here, the focus stacking type is, for example, a type in which the near point and the far point are automatically set by pointing one point on the live view for the first on type, and a near point on the live view for the second on type. and the far point, and the off type does not perform focus stacking.

Next, FIG. 3 is a diagram showing an example of changes in the effective focal length when the distance to the object to be photographed changes.

When the distance to the object to be photographed (the distance along the optical axis from the imaging surface of the image pickup device to the object to be photographed) changes from the long distance side to the short distance side, the distance is constant, from infinity to about 400 mm in the example of FIG. Until then, the effective focal length of the photographing lens 2 is kept substantially constant (nominal focal length f of about 85 mm in the example of FIG. 3).

When the distance to the photographing object changes from about 400 mm to the short distance side, the effective focal length of the photographing lens 2 gradually becomes shorter than the nominal focal length f (the shortened focal length is indicated by Δf). In the example of FIG. 3, the effective focal length of the photographing lens 2 is up to about 70 mm at the shortest distance (the distance to the photographing object is about 300 mm).

That is, the example of FIG. 3 is an example in which the angle of view of the photographing lens 2 changes to the wide-angle side during short-distance photographing. A macro lens configured as an inner focus lens (IF (Inner Focus) lens) is an example of a lens that causes such a change in effective focal length. Further, other examples of lenses in which the effective focal length changes include a rear focus lens, a front lens extension type lens, and the like. An example of a lens in which the effective focal length does not change is a lens of the all-group extension type.

In the present embodiment, as shown in FIG. 3, the photographing lens 2, which is the target for displaying the view angle range of the focus stacking image, changes when the distance to the photographing object changes (that is, when the focus position changes). The lens is configured so that the effective focal length changes.

Further, FIG. 4 is a diagram showing an example of change in image magnification when the distance to the object to be photographed changes, in comparison with when the effective focal length changes and when it does not.

The image magnification M is obtained by using the distance L to the object to be photographed and the nominal focal length f.
M=f/(L−f)
is represented by As shown by the above formula, the image magnification M is a function of the distance L to the object to be photographed.

However, as shown in FIG. 3, when photographing at a short distance, the focal length of the photographing lens 2 changes by Δf toward the wide-angle side, and the effective focal length becomes (f−Δf). Therefore, the image magnification M when photographing at a short distance is
M=(f−Δf)/{L−(f−Δf)}
is represented by

The graph of FIG. 4 shows such changes in the image magnification M. If the effective focal length does not change, the virtual image magnification M shown by the dotted line is obtained during short-distance photography. On the other hand, in the case of the taking lens 2 of the present embodiment, in which the effective focal length changes according to the focus position, the solid line indicates that the image magnification M on the short-distance side changes as the effective focal length changes. It is smaller than the virtual image magnification M when it is not used. It should be noted here that the virtual image magnification is meaningless since it is actually outside the focus range. The shortest photographable distance at which focusing is possible when the effective focal length does not change is point B shown in FIG. 4, and the shortest photographable distance when the effective focal length is allowed to change is point A shown in FIG. That is, although the effective focal length changes, the image magnification at point A can be larger than the image magnification at point B, which is preferable from a practical point of view. However, a problem arises when the focus stacking shooting range is not beyond the B point.

FIG. 5 is a diagram showing how the angle of view changes according to the focus stacking direction and the focus position when focus stacking is performed with changes in the effective focal length as described above. A hatched portion in the drawing indicates a portion in focus. Also shown is a display example of the angle of view limitation according to on/off of camera shake correction at the far point.

In FIG. 5, in the case of the first focus stacking shooting direction, a plurality of images are acquired while moving the focus position from the near point to the far point. The angle of view is wide on the dot side.

Therefore, when focus stacking photography is first started from the near point side, the release button 44a is pressed while viewing a live view image with a wide angle of view. It will be generated.

Specifically, in the near-point image I1, another subject appears behind the target subject, but in the image I2 obtained by moving the focus position toward the far point, the other subject is further out of the image. In the far point image I3 and the far point image I4, which are moved in the direction of the far point, no other subject is captured. Since the focus stacking image is generated by matching the angle of view with the far point image I4 having the narrowest angle of view, other subjects are not captured in the focus stacking image.

In the case of the second focus stacking shooting direction in FIG. 5, on the contrary, focus stacking shooting is started from the far point, and shooting is sequentially performed toward the near point side. In this case, you are looking at the live view image with the narrowest angle of view. Therefore, the user can obtain a focus stacking image with the desired angle of view when the release button 44a is pressed, even without displaying the angle of view limit on the live view.

Note that when the user is hand-held and the camera shake correction function is turned off, as shown in the image I4nis in the lower part of FIG. It is good to show a frame indicating that the range will be narrowed. On the other hand, when the camera shake correction function is turned on and the camera shake can be effectively corrected within the movable range of the camera shake correction, the frame indicating the narrowing of the angle of view is displayed as shown in the image I4is. Optional.

FIG. 6 is a flow chart showing main processing in the imaging device 1 .

When the imaging device 1 is powered on, the processing shown in FIG. 6 is started.

After various initializations associated with power-on are performed, lens information acquisition processing is performed (step S1). Here, the system control unit 48 acquires various information related to the photographing lens 2 from the communication control unit 29 via the lens communication unit 37 and electrical contacts of the lens mount.

Then, the system control unit 48 checks the focus stacking flag set in the imaging device 1 (step S2). As will be described later with reference to FIG. 7, this focus stacking flag indicates that the photographing lens 2 attached to the camera body 3 is a lens capable of focus stacking (focus stacking target lens) and When the shooting mode is set, it becomes "1" (on). Also, if the photographing lens 2 is not a focus stacking target lens, or if the focus stacking target lens is not set to the focus stacking shooting mode, it is set to "0" (off).

Note that the setting of the focus stacking photography mode is performed using a menu displayed on the display unit 43 or by pressing the focus stacking button 44i.

Here, when it is determined that the focus stacking flag is "0", the display unit 43 performs live view display for shooting other than for focus stacking based on the control of the system control unit 48 (step S3). ).

Further, when it is determined in step S2 that the focus stacking flag is "1", the system control unit 48 performs focus stacking shooting interlock setting processing (step S4). This focus stacking shooting interlocking setting is a process of changing the shooting settings suitable for focus stacking shooting based on the shooting settings before setting focus stacking shooting as shown in FIGS. 8 and 9 . As will be described later, there are two types of linked settings: fixed shooting settings and user-selectable shooting settings.

Subsequently, under the control of the system control unit 48, the display unit 43 performs focus stacking live view display (step S5).

After the processing of step S3 or step S5 is performed, the system control unit 48 determines whether or not the release button 44a as an operation member of the operation unit 44 has been operated (step S6).

Here, when it is determined that an operating member other than the release button 44a has been operated, the system control unit 48 performs processing (operating member processing) according to a signal from the operated operating member (step S7). ).

The operation member processing includes, for example, acquisition of new lens information and setting of a display update flag when pressing of the lens removal button is detected (that is, detection of replacement of the photographing lens 2), and processing when a zoom operation is detected. Acquisition of lens information and setting of display update flag, focus stacking button press processing when pressing of focus stacking button 44i is detected, focus processing and display update flag setting when focus operation is detected, touch panel operation is detected , setting of a display update flag when detecting the start of live view display, and setting of AF and display update flags when detecting a change in the shooting distance.

Here, as described above, the focus stacking button pressing process performs the transition between the normal shooting mode and the focus stacking shooting mode, the setting of the focus stacking type, the setting of the parameters at the time of focus stacking shooting, etc. according to the operation mode. processing. Here, the focus stacking type includes a type (first on-type) in which the focus range of focus stacking is set based on the user's designation of one of the shooting start point and the shooting end point, and and a type (second ON type) that sets the focus range for focus stacking based on the designation of two end points. Parameters for focus stacking photography include, for example, whether focus stacking is performed from the near point to the far point or from the far point to the near point (focus movement direction), the far point side in focus stacking shooting, There are the number of shots, the number of shots on the near point side, the focus step, and so on. Note that the focus step is a unit of the amount of focus movement, and is set by, for example, multiplying the value F δ obtained by multiplying the diameter δ of the circle of least confusion by the aperture value F of the photographing lens 2 by a fraction of 1 or less. . Therefore, changing the focus step is done by changing the fraction less than or equal to 1 by which Fδ is multiplied.

As for the touch operation processing, normal touch operation processing is performed when the focus stacking flag is "0", and focus stacking touch operation processing is performed when the focus stacking flag is "1". Here, the focus stacking touch operation processing is processing for determining the near point and the far point in focus stacking photography.

When the focus stacking type is the above-described second on-type, the near point and far point can be set by simultaneously touching two points on the touch panel, touching and tracing one point on the touch panel, or touching the touch panel twice. done. In the case of the second on-type, the point moved from the focus position of the point touched on the near point side to the near point side by the "number of shots on the near point side" (that is, the number of margins on the near point side). The point that is set as the true near point and moved from the point touched on the far point side to the far point side by the "number of shots at the far point side" (that is, the number of shots at the far point side) is the true far point. set to a point.

On the other hand, when the focus stacking type is the above-described first ON type, the near point and far point settings are based on the menu setting based on one-point touch on the touch panel (as described above, the one touched point is used as the reference setting of the number of shots on the far point side, the number of shots on the near point side, focus steps, etc.). In other words, the point that moves the focus toward the near point by the "number of shots on the near point side" from the one touched focus position is set as the near point, and the "far point side shot" from the touched one point focus position. The far point is set to the point where the focus has been moved to the far point side by the "number of images".

The determination of the near point and the far point in the touch operation process is performed when the AF scanning between the two points is successful, that is, when the set near point and far point are focused. Also, after the near point and far point are determined, it is determined whether the number of shots is within a predetermined value. modified as follows: In addition, if the AF scan is not successful, or if the number of shots does not fall within a predetermined value even if the focus step is coarsened, a warning is displayed and the near point and far point specified in touch operation processing are invalidated. It is said that

When it is determined in step S6 that the release button 44a has been operated, the system control unit 48 determines whether or not the 1st release switch is on (step S8).

Here, when it is determined that the 1st release switch is on, 1st on processing is performed based on the control of the system control section 48 (step S9). Here, AF/photometry processing is performed in the 1st ON processing. However, in focus stacking photography, single AF (S-AF) may be performed according to operation of other appropriate operation buttons without performing AF processing in the 1st ON processing. In particular, when the focus stacking type is the 2nd ON type, or even if the focus stacking type is the 1st ON type, when the far point or the near point of focus stacking is determined by an operation other than the 1st ON process, the 1st ON process It is desirable that the AF processing is not performed at , and only the photometric processing is performed.

Subsequently, the system control unit 48 determines whether or not the second release switch is on (step S10).

Here, when it is determined that the second release switch is on, the system control unit 48 further checks the focus stacking flag (step S11).

Here, when it is determined that the focus stacking flag is "0", still image shooting processing corresponding to a shooting mode other than the focus stacking shooting mode is performed based on the control of the system control unit 48 (step S12). ).

Further, when it is determined in step S11 that the focus stacking flag is “1”, processing of still image shooting for focus stacking shooting (main shooting of focus stacking shooting) is performed based on the control of the system control unit 48. is performed (step S13).

Then, the image processing unit 34 performs focus stacking processing on the acquired plurality of images under the control of the system control unit 48 (step S14), and the system control unit 48 performs recording processing in the external memory 42 (step S15). .

In the recording process of step S15, the JPEG file is recorded in the current folder of the external memory 42 when the image recording mode is set to JPEG only. Further, when the image recording mode is set to RAW+JPEG, the RAW image recording mode is set only for the RAW image that has been focus-stacked, or the RAW image that has been focus-stacked and the is set to record a plurality of RAW images. Then, if only the RAW image with depth stacking is set, the JPEG file and the depth stacking RAW image file are recorded in the current folder. On the other hand, if the setting is made to record multiple RAW images before focus stacking, the number of files to be recorded increases. , a JPEG file, a focus stacking RAW image file, and a plurality of RAW image files before focus stacking are recorded.

Here, when RAW+JPEG is set as the image recording mode, and a setting is made to record a plurality of RAW images before focus stacking, the JPEG image generated as the focus stacking image and the focus stacking RAW The images are images within the angle-of-view restriction frame, but the plurality of RAW images before focus stacking are images with an angle of view displayed on the entire display unit 43 . Therefore, in the live view display for focus stacking shooting (step S5) in such a case, it is possible to confirm both the angle of view range of the JPEG image (or the focus stacking RAW image) and the range of view of the RAW image before focus stacking. It is preferable to adopt ruled line display or semi-transparent display that can be used rather than to adopt opaque display. On the other hand, when only JPEG is set as the image recording mode, opaque display may be adopted. Therefore, the display method of the view angle restriction frame may be changed according to the setting of the image recording mode. Incidentally, effective focal length information at the time of shooting or information based thereon is recorded as Exif information for a plurality of RAW images in consideration of performing focus stacking processing by RAW development.

After performing the process of step S15, step S12, or step S7, the system control unit 48 determines whether or not the power-off operation has been performed (step S16).

Here, if it is determined that the power off operation has not been performed, if it is determined that the 1st release switch is off in step S8, or if it is determined that the 2nd release switch is off in step S10, returns to step S1 and performs the above-described processing.

Further, when it is determined in step S16 that the power-off operation has been performed, the focus lens and the camera-shake correction optical element 23 are returned to their initial positions under the control of the system control unit 48, and the display unit 43 is turned off. is performed (step S17), and then this process is terminated.

Next, FIG. 7 is a flowchart showing lens information acquisition processing in step S1 of FIG.

When entering this process, the system control unit 48 communicates with the communication control unit 29 via the lens communication unit 37 (step S21).

Then, the system control unit 48 acquires lens basic information from the communication control unit 29 (step S22). The lens basic information acquired here includes, for example, lens ID (lens type name, lens serial number, etc.), lens F value (minimum value to maximum value), shortest shooting distance, nominal focal length, lens color temperature, infinity The lens extension pulse amount from (∞) to the closest object, and the like.

Next, the system control unit 48 acquires the effective focal length of infinity (∞) (matching the nominal focal length unless it is a special lens) (step S23), and acquires the effective focal length of the shortest shooting distance. (Step S24), the effective focal length at the current focus position (focus position) is acquired (Step S25).

However, what is acquired in steps S23 to S25 is not limited to the effective focal length, and the effective imaging angle of view may be acquired, or other parameters corresponding to the effective imaging angle of view may be acquired. Then, based on the information acquired in steps S23 to S25, the display of the "focus stacking angle of view" in the live view is performed as described later.

Also, the effective focal length (one of the parameters corresponding to the effective imaging angle of view) is not limited to being obtained from the imaging lens 2 . For example, a table indicating the relationship between the focus position and the effective focal length is prepared in the non-volatile memory 41 of the camera body 3 or the like for each type of the taking lens 2. Based on the table related to 2, obtain the effective focal length at infinity (∞) and the closest distance by referring to the table. Interpolation calculation may be performed.

Subsequently, the system control unit 48 acquires focus stacking target lens information (step S26). This focus stacking target lens information is information indicating whether or not the photographing lens 2 is a focus stacking target lens.

Note that the focus stacking target lens information may be obtained by pre-storing a flag indicating that the lens is a "focus stacking target lens" in the storage unit of the photographing lens 2, and reading this flag.

Here, the condition for being a "focus stacking target lens" is that a command to move the focus position from the camera body 3 is forcibly accepted and the focus can be moved in the focus steps required for focus stacking. That is, in automatic focus stacking photography, it is necessary to automatically change the focus position. For this reason, a lens dedicated to manual focus whose focus position is changed only manually is excluded from focus stacking target lenses. In addition, there is a lens that can be set to MF/AF, which is not a focus stacking target lens in the MF setting state but is a focus stacking target lens in the AF setting state. Some lenses that can be set to MF/AF can accept the above command regardless of the setting.

Further, the focus stacking target lens information is not limited to being acquired from the photographing lens 2, and is stored in the non-volatile memory 41 of the camera body 3 in a table indicating the correspondence between the "lens type name" and the "focus stacking target lens". is prepared in advance, and by referring to a table based on the "lens type name" acquired from the photographing lens 2, whether or not it is a focus stacking target lens may be determined.

Then, based on the focus stacking target lens information acquired in step S26, the system control unit 48 determines whether or not the photographing lens 2 attached to the camera body 3 is a focus stacking target lens (step S27). ).

Here, the system control unit 48 sets the focus stacking lens attachment flag to 1 when it is determined that the lens is the subject of focus stacking (step S28), and when it is determined that the lens is not the subject of focus stacking. A lens attachment flag is set to 0 (step S29).

When step S28 is performed, the system control unit 48 further checks the focus stacking valid flag (step S30). Here, the focus stacking effective flag is a flag indicating whether or not the focus stacking shooting mode is set. This focus stacking effective flag can be set to "1" (on) only when the focus stacking target lens is attached, and when the focus stacking effective flag is "0" (off) Focus stacking cannot be performed on

If the focus stacking effective flag is determined to be "1" in step S30, the system control unit 48 sets the focus stacking flag to "1" (step S31).

Further, when it is determined in step S30 that the focus stacking effective flag is "0", or when the process of step S29 is performed, the system control unit 48 sets the focus stacking flag to "0" (step S32).

In this way, the system control unit 48 functions as a focus stacking enable/disable determination unit (focus stack enable/disable determination circuit) that determines whether focus stacking photography is possible based on the information of the photographing lens 2. .

After the processing of step S31 or step S32 has been performed in this way, the processing returns from this processing.

FIG. 8 is a flow chart showing the processing for the focus stacking shooting interlocking setting in step S4 of FIG.

When entering this process, the system control unit 48 checks the shake correction linked menu (step S41). It is rational that the camera shake correction is automatically set when shooting handheld, but there are cases where the user does not want the camera shake correction function to operate. For example, in a photographic lens equipped with the L-IS function, the L-IS function is automatically turned on during focus stacking photography even though the L-IS function is turned off (or conversely, If the L-IS function is turned off automatically even though the L-IS function is set to on), the user may feel uncomfortable. For this reason, in the present embodiment, an item for selecting whether or not to interlock image stabilization with focus stacking photography is explicitly provided in the menu.

If it is determined here that the camera shake correction interlocking is to be performed, the system control unit 48 performs the camera shake correction interlocking process (step S42).

If the processing of step S42 is performed, or if it is determined that the shutter mode is not interlocked in step S41, the system control unit 48 checks the shutter mode interlocking menu (step S43).

If it is determined here that the shutter mode interlocking is to be performed, the system control unit 48 checks the current shutter mode (step S44).

Then, when it is determined that the mechanical shutter is currently set, the system control unit 48 changes the shutter mode to the electronic shutter (step S45).

There are two types of shutter modes, an electronic shutter mode and a mechanical shutter mode. Since the mechanical shutter requires time to charge the shutter, the continuous shooting speed is lower than that of the electronic shutter. This means that the total shooting time is lengthened, and means that the shooting angle of view for focus stacking is unnecessarily narrowed when hand-held shooting is performed without optical camera shake correction. Furthermore, since the mechanical shutter is configured to run the shutter curtain, shutter shock occurs, and the faster the continuous shooting speed, the greater the shutter shock. Shooting with a shutter speed of For this reason, the electronic shutter is automatically set when the shutter mode is interlocked. Here, the electronic shutter may be either an electronic rolling shutter or an electronic global shutter.

However, when the flash unit 47 emits illumination light, the current synchronization speed is 1/60 to 1/100 (seconds) of the electronic shutter, while the mechanical shutter is 1/250 to 1/500 (seconds). seconds) and faster, it allows you to select the mechanical shutter in the menu. Mechanical shutters are available in two types: a type that runs physical shutter curtains for both the front and rear curtains, and a hybrid type that uses an electronic shutter for the front curtain and a physical shutter curtain for the rear curtain (electronic front curtain). shutter).

If the process of step S45 is performed, if it is determined in step S43 that the shutter mode is not interlocked, or if it is determined in step S44 that the electronic shutter is set, the system control unit 48 sets the shutter speed. Check the restriction interlock menu (step S46).

Here, when it is determined that the shutter speed limit interlocking operation is to be performed, the system controls whether or not the imaging device 1 is in the state of hand-held shooting based on the output of the angular velocity sensor, acceleration sensor, etc. provided in the camera shake detection unit 38. The unit 48 determines (step S47).

If it is determined that the camera is hand-held, the system control unit 48 limits the shutter speed to a lower speed so that the shutter speed is equal to or higher than a predetermined shutter speed (step S48).

The faster the continuous shooting speed of focus stacking shooting, the less the angle of view limitation due to camera shake. In particular, in order to reduce the effects of hand-held camera shake, it is important to shorten the total shooting time of a plurality of consecutive shots. The upper limit of the continuous shooting speed differs between the mechanical shutter and the electronic rolling shutter because it depends on the shutter curtain speed. The standard shutter speed is 1/180 to 1/500 (seconds) for a mechanical shutter, and 1/30 to 1/120 (seconds) for an electronic rolling shutter. If the shutter speed is equal to or lower than the sync speed, the continuous shooting speed will decrease and the total shooting time will be lengthened.

If it is determined in step S46 that the shutter speed limit is not interlocked, if it is determined in step S47 that the camera is fixed to a tripod or the like instead of being hand-held, or if the process of step S48 is performed, then the following steps are taken: , the system control unit 48 checks the focus mode (step S49).

Here, when it is determined that the focus mode is constant AF or continuous AF (C-AF), the system control unit 48 prohibits constant AF (step S50) and continuously AF (C-AF). -AF) is prohibited (step S51), and the focus mode is set to single AF (S-AF) or combination of S-AF and MF (S-AF+MF) (step S52).

The final angle of view for automatic focus stacking photography depends on the difference in effective focal length between the near point and the far point. For this reason, if the AF position of the near point or the far point constantly fluctuates, the final angle of view range displayed in the live view fluctuates minutely, making it impossible to perform stable framing. For this reason, it is preferable to prohibit focus modes such as constant AF and C-AF, which may update AF at predetermined time intervals, in conjunction with the setting of automatic focus stacking photography. Therefore, here the focus mode is limited to S-AF or S-AF+MF.

Note that the method for enabling stable framing is not limited to the method of limiting the focus mode. For example, in a lens type having an AF start button, AF by half-pressing the release button 44a (change from OFF to ON of the 1st release switch: 1st release ON) is prohibited without restricting the focus mode, and the AF start button is pressed. The AF operation may be performed only when the button is pressed. In this case, since the focus position is locked when the AF start button is released, the angle of view does not fluctuate finely when checking the angle of view even in the C-AF mode.

If the process of step S52 is performed, or if it is determined in step S49 that the focus mode is single AF (S-AF), manual focus (MF), or combination of S-AF and MF (S-AF+MF) Then, the system control unit 48 checks the continuous shooting mode (step S53).

There are two types of continuous shooting modes: AE lock continuous shooting in which AE is continued for the first frame of continuous shooting, and AE tracking continuous shooting in which AE is performed for each continuous shooting frame. slows down the continuous shooting speed compared to AE lock continuous shooting. Also, when AE tracking continuous shooting is performed, the brightness of each frame is not uniform due to the change in the angle of view. It takes time. Therefore, from the viewpoint of shortening the shooting time and shortening the processing time after shooting, AE lock continuous shooting is preferable as the continuous shooting mode for automatic focus stacking shooting.

Therefore, when it is determined in step S53 that AE tracking continuous shooting is to be performed, the system control unit 48 changes the continuous shooting mode to AE lock continuous shooting (step S54).

If the process of step S54 is performed, or if it is determined to be AE lock continuous shooting in step S53, the system control unit 48 determines whether or not the high resolution shot is on (step S55).

A high-resolution shot (high-resolution photographing) mode is a photographing mode in which photographing with pixel shifts is repeated a plurality of times to generate one high-definition image from a plurality of pixel-shifted images. Focus stacking mode is a shooting mode that repeats shooting multiple times each time the focus is shifted. This dramatically increases the total shooting time, leading to large camera shake in hand-held shooting. In addition, since the number of shots is large, the time required for compositing processing after shooting is long. Therefore, an extremely large-capacity buffer is required, which leads to an increase in cost).

Therefore, when it is determined in step S55 that the high resolution shot is on, the system control unit 48 performs high resolution shot interlocking processing that is optimal for focus stacking (step S56).

A first example of high-resolution shot interlocking processing determines whether the high-resolution shot mode is tripod high-resolution shot, hand-held high-resolution shot, or automatic switching. In order to suppress the lengthening of the time, the number of pixel shifts is made smaller than usual. Specifically, the number of pixel shifts is automatically set to 4 times or less, for example, 4 times or 2 times.

The second example of the high-res shot interlocking process performs the same determination as the first example, and automatically switches the high-res shot mode to the tripod high-res shot when the high-res shot mode is hand-held high-res shot or automatic switching. It is. This limits high-res shots when focus stacking is on to tripod high-res shots.

A third example of high-resolution shot interlocking processing is to prohibit high-resolution shots when focus stacking photography is on.

A fourth example of high-resolution shot interlocking processing prohibits focus stacking photography when high-resolution shot is turned on while focus stacking photography is on.

If the process of step S56 is performed, or if it is determined in step S55 that the high resolution shot is off, the system control unit 48 checks the digital teleconverter (digital teleconverter) linked menu (step S57).

If it is determined to be interlocked here, the system control unit 48 turns on the digital teleconverter (step S58).

A digital teleconverter can provide a large image magnification and a sufficient working distance, and is therefore suitable for macro photography, and is therefore favored by users who perform macro photography. For this reason, it is desirable that the digital teleconverter is also linked with focus stacking photography, which is mainly macro photography.

Subsequently, the system control unit 48 sets the digital teleconverter magnification (digital teleconverter magnification) (step S59).

If the digital teleconverter magnification is set to an appropriate magnification, there is no need to display the field angle restriction frame for focus stacking. However, in order to prevent significant deterioration in image quality, it is desirable that the digital teleconverter magnification be as small as possible, for example, it should be suppressed to 2.0 times or less.

Specifically, it is preferable to select the smallest digital teleconverter magnification that allows the display area of the digital teleconverter to be inside the focus stacking angle of view limit frame. It is about 1.4 times.

Such an appropriate magnification is predetermined as a series value of the digital teleconverter magnification (specific examples include series values such as 1.4 times, 1.7 times, 2.0 times, and 2.8 times). If the value is not in the series value, it may be configured to separately adopt a value outside the series value.

If the process of step S59 is performed, or if it is determined that there is no interlocking in step S57, the system control unit 48 checks the AF operation member interlocking menu (step S60).

If it is determined here that they are interlocked, the system control unit 48 prohibits AF by first release-on (step S61), and sets the AF button to single AF (S-AF) (step S62).

If the process of step S62 is performed, or if it is determined in step S60 that there is no interlocking, the process returns.

FIG. 9 is a flow chart showing the camera shake correction interlocking process in step S42 of FIG.

When entering this process, the system control unit 48 checks whether or not hand-held shooting is performed (step S71). It should be noted that the determination in step S71 may be omitted in the case of a camera shake correction mechanism that does not overcompensate even in a non-handheld state such as a tripod state.

Here, if it is determined that hand-held photography is performed, the system control unit 48 further determines whether the photographing lens 2 attached to the camera body 3 is an anti-shake lens with an IS (Image Stabilization) switch. It is checked whether it is other than that (non-shake correction lens or shake correction lens without IS switch) (step S72).

It should be noted that lens IS priority is given to an image stabilization lens with an IS switch. Also, in the case of a camera shake correction lens without an IS switch, it is set by a menu whether to give priority to lens IS or to give priority to body IS. Furthermore, body IS priority is automatically set for a non-shake correction lens.

If it is determined that the camera shake correction lens is equipped with an IS switch, the system control unit 48 controls to turn on the rotation camera shake correction and the shift shake correction of the body IS (step S73).

As described above, camera shake includes two types of angular shake caused by tilting the imaging device 1 in the yaw direction and the pitch direction, Two types of shift blur due to parallel shift in the x-axis and y-axis directions, and rotational blur due to rotation of the imaging device 1 in the roll direction (direction around the optical axis of the photographing lens 2). There are 5 types. The body IS can correct any of these five types of camera shake.

In contrast, the lens IS can correct two types of angular blur, but not rotational blur, and may or may not be able to correct two types of shift blur. In general, correction is often not possible. Therefore, in step S73, it is set so that the rotation camera shake correction and the shift shake correction are complemented by the body IS side.

If it is determined otherwise in step S72, the system control unit 48 sets the lens camera shake correction priority to off (step S74). As a result, priority is given to the body IS. Here, rotation camera shake correction and shift camera shake correction are always performed on the body IS during focus stacking photography.

Further, when it is determined in step S71 that the hand-held shooting is not performed, the system control unit 48 sets the camera shake correction mode to off (step S75). Here, there is no angle of view limitation caused by camera shake.

After performing the process of step S73 or step S74, the system control unit 48 sets the camera shake correction mode to S-IS1 or SIS_AUTO, which performs camera shake correction in all directions (step S76).

Here, the camera shake correction mode includes S-IS_AUTO that detects the movement and camera shake of the imaging device 1 and automatically corrects the camera shake in the optimum direction, S-IS1 that performs camera shake correction in all directions, and the image pickup device. 1, S-IS2 for performing only vertical motion compensation, S-IS3 for performing only horizontal motion compensation for the imaging apparatus 1, and S-ISOOFF for performing no motion compensation. S-IS means still-image stabilization, and moving-image stabilization is M-IS (moving-image stabilizer).

Subsequently, the system control unit 48 sets the camera shake correction mode during continuous shooting to the continuous shooting speed priority (step S77).

Here, as the camera shake correction mode during continuous shooting, two modes of continuous shooting speed priority and camera shake correction priority can be selected.

FIG. 10 is a timing chart showing an operation example of camera shake correction with priority given to continuous shooting speed and an example of a captured image, and FIG. 11 is a timing chart showing an example of camera shake correction operation with priority given to camera shake correction and an example of a captured image.

10 and 11 schematically show the blurring of the imaging device 1 during continuous shooting in focus stacking along time t. In other words, although the imaging device 1 is actually blurred, it is difficult to express it, so it is assumed that the subject is moving up and down, and the image sensor is chasing it.

The continuous shooting speed-prioritized camera shake correction shown in FIG. 10 is a mode that minimizes the change in angle of view between frames by continuously performing camera shake correction during continuous shooting. In other words, since the image sensor is not reset to the reference position for each frame of continuous shooting, the possibility of hitting the end of the movable range SR of the blur correction during exposure of any frame is higher than that of camera shake correction priority. There is no change in the angle of view between continuous shooting frames unless camera shake exceeding the movable range SR for correction occurs. In this way, the continuous shooting speed priority achieves both the continuous shooting speed, which is important for shooting moving objects, and the ease of capturing the subject.

On the other hand, the camera shake correction with camera shake correction priority shown in FIG. 11 is a mode in which the image sensor is reset to the reference position each time one frame is shot. Therefore, the possibility of hitting the end of the movable range SR of the blur correction is lower than that of the continuous shooting speed priority, and high camera shake correction performance can be guaranteed. However, as shown in the captured image of FIG. 11, a change in angle of view occurs between continuous shot frames. Furthermore, since it takes time to reset to the reference position, the continuous shooting speed becomes slower than in the case of continuous shooting speed priority, which lengthens the total shooting time.

Normally, as shown in FIGS. 10 and 11, camera shake during continuous shooting is low-frequency vibration, so continuous shooting may be performed as fast as possible so that all continuous shooting is completed in a period when the amount of fluctuation is small. desirable. For this reason, in focus stacking photography, in which continuous shooting frames are to be composited, the continuous shooting speed priority is forcibly set in step S77.

After performing the process of step S75 or step S77, the process returns.

FIG. 12 is a flowchart showing a first example of live view display processing for focus stacking photography in step S5 of FIG.

When entering this process, the system control unit 48 checks the display update flag (step S81).

Here, when it is determined that the display update flag is "1" (on), the process of specifying the focus stacking angle of view range is performed based on the control of the system control unit 48 (step S82).

Next, display update processing of the focus stacking angle of view range is performed under the control of the system control unit 48 (step S83).

After that, the system control unit 48 resets the display update flag to "0" (off) (step S84).

If the process of step S84 is performed, or if it is determined that the display update flag is "0" in step S81, the process returns.

FIG. 13 is a flow chart showing a second example of the focus stacking live view display process in step S5 of FIG.

When entering this process, the system control unit 48 determines whether or not the far point in focus stacking photography has been determined (step S91).

If it is determined that the far point is fixed, the system control unit 48 determines whether or not the current focus position is near the far point (step S92).

Note that the vicinity of the far point refers to a focus position including the far point and having an effective focal length substantially equal to the far point. If the live view focus position during shooting standby is near the far point, the live view is performed at the narrowest angle of view in focus stacking shooting. no longer need to be displayed in

If it is determined in step S92 that it is not near the far point, the lens control unit 26 moves the focus position to the far point or near the far point under the control of the system control unit 48 (step S93).

That is, the lens control unit 26 functions as a focus position setting unit (focus position setting circuit), and in a state of waiting for the actual shooting of the focus stacking shooting, the focus stacking focus position determination unit (focus stacking focus position determination circuit ), the live view focus position is set in the vicinity of the far point focus position determined by the system control unit 48 that functions as .

As a result, as described above, it is no longer necessary to display the view angle limit range due to the effective focal length in the live view.

Then, under the control of the system control unit 48, the process of specifying the focus stacking angle of view range is performed (step S94), and the display update process of the focus stacking view angle range is performed (step S95).

If the process of step S95 is performed, or if it is determined in step S91 that the far point has not been determined, or if it is determined in step S92 that the current focus position is near the far point, this process is terminated. return.

12 and 13 can be selected by menu setting.

FIG. 14 is a flow chart showing a first example of processing for specifying the focus stacking angle of view range in step S82 of FIG. 12 and step S94 of FIG.

This first example is an example of calculating the focus stacking angle of view range when the live view effective focal length at the current focus position (reference point) and the far point effective focal length in focus stacking photography are determined. It has become. Here, the focus stacking angle of view range changes according to the type of the photographing lens 2, the effective focal length at the current focus position, the focus movement direction, and the range conditions from the near point to the far point of focus stacking photography set by the user. .

When entering this process, the system control unit 48 acquires the far point focus position (focus position) in focus stacking photography (step S101), and acquires the effective focal length ffar of the far point focus position (step S102).

Furthermore, the system control unit 48 acquires the effective focal length fbase of the current focus position (step S103).

Then, the system control unit 48 calculates the effective focal length ratio R between the effective focal length ffar at the far point focus position and the effective focal length fbase at the current focus position,
R=(fbase/ffar)×100
(step S104).

Subsequently, the system control unit 48 determines whether or not camera shake correction is effective (step S105).

Here, if the user has set the camera shake correction not to be linked to the focus stacking shooting, and if the camera shake correction is set to OFF even though the shooting is handheld, it is determined that the camera shake correction is not effective. Then, the system control unit 48 corrects the effective focal length ratio R in consideration of the ratio ΔR corresponding to the camera shake correction, and sets R−ΔR as the post-correction effective focal length ratio R (step S106).

Specifically, it is preferable to set ΔR to a value of about 14% to 20% as an empirical value in both the vertical and horizontal directions of the image at infinity.

If the process of step S106 is performed, or if it is determined in step S105 that the camera shake correction is effective, the process returns.

In this case, ΔR was not corrected when the camera shake correction was turned on (enabled), but considering the correction performance of the camera shake correction, if necessary, ΔR is set to several percent (for example, 2 to 3%). It may be set to a degree and corrected.

In this way, when the processing of FIG. 14 is performed, in the processing of step S83 of FIG. 12 or step S95 of FIG. In response to a change in at least one of the information of the photographing lens 2, the output contents of the system control unit 48 functioning as a focus position determination unit for focus stacking (focus position determination circuit for focus stacking), and the shooting distance, live The display of the view angle range of the depth stacking image is updated based on the effective focal length when the view is displayed and the effective focal length when the far point focus position is set.

FIG. 15 is a flow chart showing a second example of the process of specifying the focus stacking angle of view range in step S82 of FIG. 12 and step S94 of FIG.

In this second example, the focus stacking angle range is calculated when the angle of view of the live view image and the focus stacking image in the photographing lens 2 attached to the camera body 3 is the most different, and the calculated focus stacking This is an example of displaying a fixed angle of view range. When this processing is performed, the displayed focus stacking angle of view range may become narrower than necessary, but the display range changes depending only on the type of the photographing lens 2, and the user's setting conditions (current focus position) , focus movement direction, positions of the near point and the far point, etc.).

When entering this process, the system control unit 48 acquires the effective focal length f∞ of the focus position (focus position) at the point at infinity (∞) (step S111).

Furthermore, the system control unit 48 acquires the effective focal length fnearest of the focus position of the closest point (step S112).

Then, the system control unit 48 calculates the effective focal length ratio R between the effective focal length f∞ at the focus position at infinity and the effective focal length fnearest at the focus position at the closest point,
R=(fnearest/f∞)×100
(step S113).

Therefore, the system control unit 48 functions as a maximum angle-of-view variation determination unit (maximum angle-of-view variation determination circuit), and based on the information of the imaging lens 2, the maximum focus position of the imaging lens 2 within the movable range. A field angle variation amount (maximum field angle variation amount obtained from the maximum and minimum values of the effective focal length) is determined.

Subsequently, the system control unit 48 acquires the effective focal length fbase of the current focus position (step S114). The reason why the effective focal length fbase is acquired here is that it will be used when determining the final angle of view of the depth stacking image later. Here, the angle of view corresponding to the value (fbase×R) obtained by multiplying the effective focal length ratio R finally determined in the processing of FIG. It becomes the angle of view of the frame. Therefore, regardless of the current focus position from the closest point to the infinity (∞), the view angle restriction frame displayed in the live view is a frame display with a constant effective focal length ratio R.

After that, the system control unit 48 determines whether or not the camera shake correction is effective (step S115).

Here, when it is determined that the camera shake correction is invalid, the system control unit 48 corrects the effective focal length ratio R in consideration of the ratio ΔR corresponding to the camera shake correction, and corrects R−ΔR. A later effective focal length ratio R is set (step S116).

If the process of step S116 is performed, or if it is determined in step S115 that the camera shake correction is effective, the process returns.

It should be noted that, similarly to the above, the empirical value of the ratio ΔR and the correction by ΔR may be performed when the camera shake correction is turned on (enabled).

In this way, when the processing of FIG. 15 is performed, in the processing of step S83 of FIG. 12 or step S95 of FIG. The view angle range of the focus stacking image based on the maximum view angle variation amount is displayed on the live view.

FIG. 16 is a flow chart showing a third example of the process of specifying the focus stacking angle of view range in step S82 of FIG. 12 and step S94 of FIG.

This third example is the case where the angle of view between the live view image and the focus stacking image differs the most in the plurality of shooting lenses 2 (focus stacking target lens group) that can be attached to the camera body 3 and are subject to focus stacking. This is an example of fixedly displaying the depth stacking angle of view range of . When this process is performed, the displayed focus stacking angle of view range may become narrower than in the example of FIG. Since it does not change depending on the conditions (current focus position, focus movement direction, near point and far point positions, etc.), this is an example that can provide the user with convenience that is easier to understand and easier to use. .

When entering this process, the system control unit 48 sets an effective focal length ratio R (this effective focal length ratio R is a value calculated in the processing of FIG. 15) for each photographing lens 2 included in the focus stacking target lens group. , is determined as R (step S121).

In this way, the system control unit 48 functioning as a maximum angle-of-view variation determination unit (maximum angle-of-view variation determination circuit) performs , the lens group maximum angle of view variation amount (corresponding to the minimum value of the effective focal length ratio R determined in step S121) having the largest variation amount among the maximum angle of view variation amounts of the photographing lens 2 included in the lens group is decide.

Next, the system control unit 48 determines whether or not camera shake correction is effective (step S122).

Here, when it is determined that the camera shake correction is invalid, the system control unit 48 corrects the effective focal length ratio R in consideration of the ratio ΔR corresponding to the camera shake correction, and corrects R−ΔR. The subsequent effective focal length ratio R is set (step S123).

If the process of step S123 is performed, or if it is determined in step S122 that the camera shake correction is effective, the process returns.

It should be noted that, similarly to the above, the empirical value of the ratio ΔR and the correction by ΔR may be performed when the camera shake correction is turned on (enabled).

In this way, when the processing of FIG. 16 is performed, in the processing of step S83 of FIG. 12 or step S95 of FIG. The field angle range of the focus stacking image based on the lens group maximum field angle fluctuation amount is displayed on the live view for any photographing lens 2 included in the lens group.

14 to 16 described above can be selected by menu setting, for example.

FIG. 17 is a flow chart showing the display update processing of the focus stacking angle of view range in step S83 of FIG. 12 and step S95 of FIG.

When entering this process, the system control unit 48 determines whether or not the digital teleconverter (digital teleconverter) is set to ON (step S131).

Here, when it is determined that the digital teleconverter is not set, the system control unit 48 determines whether or not the effective focal length ratio R is less than 98% (step S132).

Then, when it is determined to be less than 98%, the system control unit 48 controls to display a field angle restriction frame on the live view image based on the effective focal length ratio R (step S133).

On the other hand, if it is determined in step S132 that the effective focal length ratio R is 98% or more, the view angle restriction frame is not displayed.

Here, 98% is taken as an example of the criterion for determining that the view angle restriction frame display is not necessary because it can be regarded as a margin of error from 100%. A range of 97 to 100% may be used as a guideline.

As an example of the case where it is determined that the distance is 98% or more, when the photographing lens 2 is a lens of the all-group extension type and there is no change in the effective focal length, the working distance between the subject and the imaging device 1 is sufficient. For example, the change in the effective focal length from the nominal focal length is very small at the near point, and the live view waiting for automatic focus stacking photography is always the far point from before shooting to during continuous shooting.

Examples of the display of the view angle restriction frame include a ruled line display that draws a square ruled line (the ruled line may be in an appropriate color such as black, red, or green) that indicates the view angle restricted frame; Translucent display, in which the image outside the angle limiting frame is translucent, opaque display, in which the image outside the view angle limiting frame is opaque, etc., are exemplified, but not limited to these.

Note that if the recorded image is only an image within the field angle restriction frame, any of ruled line display, semi-transparent display, and opaque display may be adopted. As described above, it is preferable to adopt ruled line display or semi-transparent display when the image of .

On the other hand, if it is determined in step S131 that digital teleconverter is set, digital teleconverter display processing is performed under the control of the system control unit 48 (step S134). Here, in the digital teleconverter display, there is an enlarged live view display that enlarges and displays the image part according to the digital teleconverter magnification, and a limit frame that shows the image range according to the digital teleconverter magnification on the live view without enlargement. There is a limit frame display to be displayed, and it is possible to select which one to display from the menu.

If the process of step S133 or step S134 has been performed, or if it is determined in step S132 that the effective focal length ratio R is 98% or more, the process returns.

In the above description, the view angle limit frame is used as the display of the view angle range of the focus stacking image. It is also possible to display the view angle range of the image. This enlarged display is preferable when JPEG is set as the image recording mode, but when RAW+JPEG is set, it is preferable to use ruled line display or translucent display as described above.

Also, in the imaging device 1, it is possible to set the aspect ratio (and the number of pixels for each aspect ratio, etc.) indicating the ratio between the horizontal direction and the vertical direction of the image using an aspect ratio setting section such as a menu. Examples of aspect ratios that can be set here include 4:3, 3:2, 16:9, 1:1, and 3:4. It is also assumed that the aspect ratio of the imaging device of the imaging unit 31 is 4:3, for example. At this time, when an aspect ratio other than 4:3 is set, a view angle restriction frame corresponding to the set aspect ratio is displayed within the view angle restriction range of focus stacking.

FIG. 18 is a flow chart showing the digital teleconverter display processing in step S134 of FIG.

Upon entering this process, the system control unit 48 sets the teleconverter ratio (teleconverter ratio) TR to
TR=100/DTM
(step S141).

Next, the system control unit 48 determines whether the digital teleconverter display mode is set to the enlarged live view display mode or the restricted frame display mode (step S142).

Here, when it is determined that the enlarged live view display mode is set, the system control unit 48 determines whether or not the teleconverter ratio TR is equal to or less than the effective focal length ratio R (step S143).

Then, when it is determined that the teleconverter ratio TR is greater than the effective focal length ratio R, the system control unit 48 sets R/TR as a new effective focal length ratio R (step S144).

On the other hand, if it is determined in step S142 that the restricted frame display mode is set, the system control unit 48 determines whether or not the teleconverter ratio TR is equal to or less than the effective focal length ratio R (step S145). .

Then, when it is determined that the teleconverter ratio TR is equal to or less than the effective focal length ratio R, the system control unit 48 sets TR as a new effective focal length ratio R (step S146).

Either step S144 or step S146 is performed, or if it is determined in step S143 that the teleconverter ratio TR is equal to or less than the effective focal length ratio R, or in step S145 it is determined that the teleconverter ratio TR is greater than the effective focal length ratio R. If so, the display unit 43 displays the live view view angle restriction frame based on the effective focal length ratio R under the control of the system control unit 48 (step S147).

However, the view angle restriction frame due to the change in effective focal length is substantially displayed when it is determined in step S143 or step S145 that the teleconverter ratio TR is greater than the effective focal length ratio R. Then, what is displayed when step S146 is executed is a restriction frame indicating the image range corresponding to the digital teleconverter magnification. On the other hand, if it is determined in step S143 that the teleconverter ratio TR is less than or equal to the effective focal length ratio R, the view angle limiting frame is not displayed because the enlarged live view display is performed.

In this way, the display unit 43, which is a focus stacking view angle range display unit (focus stacking view angle range display), displays the smaller one of the view angle range of the focus stacking image and the view angle range by the digital teleconverter magnification. Display the angle of view range on the live view.

After performing the process of step S147, the process returns.

FIG. 19 is a flow chart showing the still image shooting process for focus stacking shooting in step S13 of FIG.

When this process is entered, a camera shake correction process during continuous shooting is performed based on the control of the system control unit 48 (step S151).

Then, the system control unit 48 determines whether or not the near point and the far point in focus stacking photography have been determined (step S152).

If it is determined that at least one of the near point and the far point is not fixed, a warning is displayed under the control of the system control section 48 (step S153).

On the other hand, if it is determined in step S152 that the near point and far point have been determined, the system control section 48 sets the exposure delay time (step S154). Here, the exposure delay time is the time to wait for the blurring of the imaging device 1 to stop when the release button 44a is pressed.

Then, the system control unit 48 waits for the exposure delay time to elapse (step S155).

After the exposure delay time has elapsed, one-frame photographing processing is performed under the control of the system control section 48 (step S156).

In this one-frame photographing process, flash photography or non-flash photography is performed depending on whether or not flash emission is necessary, and image data obtained by photography and field angle limit range information are stored in a buffer area in memory 33. . It should be noted that the charge waiting time required for charging the flash can be specified in the menu settings related to automatic focus stacking photography.

Here, if the high resolution shot is set to ON, pixel shifting is performed, and the above-described flash photography or non-flash photography is repeatedly performed until one cycle of pixel shifting is completed.

In this way, when one frame of an image is acquired when the high resolution shot is off, or when a plurality of frames for one cycle are acquired when the high resolution shot is on, this one frame shooting is completed. .

Then, based on the control of the system control unit 48, the lens control unit 26 performs focus movement processing (step S157).

Also, under the control of the system control unit 48, a process of acquiring and displaying a live view image is performed between each frame during continuous shooting (step S158). However, if the live view display rate and the continuous shooting speed are the same, or if the continuous shooting speed is faster, images obtained by continuous shooting may be used for live view.

In live view display during continuous shooting, the focus position moves as described above, so the effective focal length also changes according to the focus position, and the angle of view of the live view image changes. In order to cope with this change in angle of view, the view angle limiting frame is enlarged or reduced for display according to the effective focal length when the live view image was acquired. Furthermore, the view angle limit frame is shifted in consideration of camera shake during continuous shooting.

Subsequently, the system control unit 48 determines whether or not the shooting of the far point and the near point has been completed (that is, whether or not all of the plurality of still images to be acquired in the focus stacking shooting have been acquired) (step S159).

Here, if it is determined that the shooting of the far point and the near point has not been completed, the process returns to step S156 to shoot the next still image.

If it is determined in step S159 that the far point and the near point have been photographed, the lens control unit 26, under the control of the system control unit 48, controls the focus position ( (reference point) (step S160).

After performing the process of step S153 or step S160, the process returns.

FIG. 20 is a flow chart showing camera shake correction processing during continuous shooting in step S151 of FIG.

When entering this process, the system control unit 48 determines whether the photographing lens 2 attached to the camera body 3 is a non-shake correction lens, a normal shake correction lens, or a BLC shake correction lens. (step S171).

Here, the BLC image stabilization lens refers to a lens capable of coordinated operation of in-body image stabilization and lens image stabilization.

When it is determined in step S171 that the photographing lens 2 is a non-shake correction lens, the body IS (B-IS) is operated under the control of the system control section 48 (step S172).

Further, in step S171, when it is determined that the photographing lens 2 is a BLC image stabilization lens, the operation of BLC-IS (coordination of in-body image stabilization and lens image stabilization) is performed under the control of the system control unit 48. is performed (step S173).

Further, when it is determined in step S171 that the photographing lens 2 is a normal camera shake correction lens, the system control unit 48 determines whether or not it is the photographing lens 2 with an IS switch (step S174). .

Here, when it is determined that the photographing lens 2 does not have an IS switch, the system control unit 48 determines whether or not the lens IS priority is turned on (step S175).

If it is determined that the lens IS priority is turned off, the process goes to step S172 to perform the operation of the body IS (B-IS).

If it is determined in step S174 that the photographing lens 2 has an IS switch, or if it is determined in step S175 that the lens IS priority is ON, the system control unit 48 controls the body IS. (B-IS) performs forced rotational shake correction (step S176), and furthermore, forced shift shake correction is performed using body IS (B-IS) (step S177).

When lens IS priority is set in this way, rotational blur correction and shift blur correction that cannot or are insufficiently corrected by lens IS should be forcibly performed by body IS. there is

Shift blur correction is important in focus stacking photography, which is often used in macro areas. Further, if rotational shake correction is performed by image processing before performing post-stage synthesis processing, the image quality deteriorates, particularly in straight line portions. Furthermore, rotational shake correction by image processing not only lowers image quality, but also extremely narrows the angle of view. Therefore, it is desirable to physically and/or optically correct rotational shake as much as possible during shooting. For this reason, the body IS is used to perform compulsory rotation blur correction and shift blur correction.

Next, the system control unit 48 determines whether the main exposure camera shake correction is set to the first mode or the second mode (step S178).

Here, if it is determined that the first mode is set, the lens IS is forcibly stopped (step S179) under the control of the system control unit 48, and the body IS performs forced camera shake correction. (Step S180).

Further, when it is determined that the second mode is set, the processing of steps S179 and S180 is not performed, and therefore camera shake correction by the lens IS is performed.

Therefore, in the case of the first mode, the lens IS is used during shooting standby, and the body IS is used during actual exposure, thereby simplifying the control. Furthermore, only the lens IS uses the movable range of image stabilization during shooting standby, and the full movable range of body IS image stabilization can be secured during actual exposure, improving image stabilization performance. There are advantages to be had.

Thus, the process of step S172, step S173, or step S180 is performed, or if it is determined that the second mode is set in step S178, the process returns.

FIG. 21 is a flowchart showing focus movement processing in step S157 of FIG.

When entering this process, the system control unit 48 determines whether or not the reference point has been moved to the vicinity of the far point (here, the vicinity of the far point includes the far point) (see steps S92, S93, etc. in FIG. 13). (step S191).

Here, when it is determined that the object has moved to the vicinity of the far point, the system control unit 48 changes the focus movement direction flag during shooting to 1 (step S192).

Here, the focus movement direction flag at the time of photographing is "0" when the focus movement direction is from the near point to the far point, and is "1" when the direction is from the far point to the near point. If the direction of focus movement is changed midway through photography, gaps and backlash will occur as a result of the change in the contact direction of the focus lens, causing a discrepancy between control and actual operation. Therefore, in order to prevent such a deviation from occurring, the focus movement direction is set to be one direction for photographing. However, since the image of the reference point is the image actually framed by the user in the live view, it is preferable to first capture the image at the start of focus stacking imaging in order to specify an accurate angle of view range.

Normally, users tend to focus on a short distance as a starting point for focus stacking photography. Also, as for the direction of focus movement during focus stacking photography, the near point→far point gives less sense of discomfort than the far point→near point. Furthermore, if the focus movement direction is changed from the far point to the near point, it is not possible to check whether or not the closest focus limit is reached, especially when specifying only the far point with a single touch. It is conceivable that the desired results may not be obtained.

Considering these points, the near point → far point is the standard direction of focus movement, and especially when the user moves the reference point to the far point, the far point → near point is changed to the focus movement direction. ing. As described above, the far point is the point at which the effective focal length is the longest (that is, the angle of view is the narrowest) in focus stacking photography. Therefore, in this case, the live view image observed by the user at the time the release button 44a is pressed to start focus stacking photography is basically the angle of view of the image obtained as a result of focus stacking, as described above. Since they match, there is no need to display the view angle limiting frame associated with focus stacking.

If the process of step S192 is performed, or if it is determined that the object has not moved to the vicinity of the far point in step S191, the system control unit 48 determines whether or not the return number is 0 (step S193). Here, the number of returned images indicates the number of images acquired by moving the focus position (focus position) from the reference point to the far point or the near point. The number of sheets to be returned can be set by a menu, and here, determination is made based on the set value of the menu.

If it is determined in step S193 that the number of returned images is not 0, the system control unit 48 determines whether or not focus position return processing has already been performed (step S194).

Here, if it is determined that the focus position return processing has not been performed yet, the lens control unit 26 performs the focus position return processing based on the control of the system control unit 48 (step S195).

By this focus position return processing, when the focus movement direction flag during shooting is 1, the focus position is moved from the reference point to the far point by the number of return images. Further, when the focus movement direction flag during shooting is 0, the focus position is moved from the reference point to the near point by the number of return images. If the reference point is moved during standby for shooting, the focus position return processing is performed after adjusting the number of return images set in the menu according to the amount of movement.

If the process of step S195 is performed, if it is determined that the return number is 0 in step S193, or if it is determined that the return process has already been performed in step S194, the system control unit 48 adjusts the focus during shooting. A movement direction flag is checked (step S196).

Here, if it is determined that the focus movement direction flag during shooting is 0, the focus is moved to the far point side by a predetermined amount (focus steps) under the control of the system control unit 48 (step S197). By this processing, the focus position is gradually moved from the near point side to the far point side.

If it is determined in step S196 that the focus movement direction flag during shooting is 1, the focus is moved by a predetermined amount (focus step) toward the near point side under the control of the system control unit 48. (step S198). By this processing, the focus position gradually moves from the far point side toward the near point side.

After performing the process of step S197 or step S198, the process returns.

FIG. 22 is a flow chart showing focus stacking processing in step S14 of FIG.

When entering this process, the system control unit 48 reads the image data of the reference point from the buffer area of the memory 33 (step S201).

After that, the image processing unit 34 functioning as a composite angle-of-view adjustment unit (composite angle-of-view adjustment circuit), based on the angle-of-view range of the focus stacking image displayed on the live view before performing the actual shooting of the focus stacking, To adjust the angle of view of each of the plurality of imaging data.

That is, first, the system control unit 48 specifies the view angle limit range A of the live view image displayed on the display unit 43 when the second release switch is turned on (step S202).

Next, based on the control of the system control unit 48, the image processing unit 34 cuts out the image data range corresponding to the view angle restriction range A from the image data of the reference point and uses it as image data B (step S203).

Further, the image processing unit 34 enlarges or reduces the image data B under the control of the system control unit 48 to standardize the number of pixels (step S204).

Then, the system control unit 48 reads the next image data from the buffer area of the memory 33 (step S205).

In addition, under the control of the system control unit 48, the image processing unit 34 cuts out the image data range corresponding to the image data B described above from the image data read out in step S205 to obtain image data C (step S206).

Subsequently, the image processing unit 34 enlarges or reduces the image data C under the control of the system control unit 48 to normalize the number of pixels (step S207).

In this way, the image processing unit 34 functions as a composite angle-of-view adjustment unit (composite angle-of-view adjustment circuit), and adjusts the angle of view of a plurality of image data based on the effective focal length when each of the plurality of image data is captured. adjust each.

Under the control of the system control unit 48, the image processing unit 34 calculates and compares the contrast value of the normalized image data B and the contrast value of the normalized image data C, and compares the contrast value of the image data B. The corresponding image area of the image data B is replaced by the image area of the image data C whose contrast value is higher than the contrast value (step S208). Although the contrast value is used here as a representative value indicating the degree of focus, this is merely an example and is not limited to the contrast value. As another embodiment, for example, high frequency components of an image may be detected and the detected high frequency components may be used as a value indicating the degree of focus.

In this way, the image processing unit 34 functions as a focus stacking unit (focus stacking circuit), and stacks a plurality of pieces of imaging data whose angle of view is adjusted to generate a focus stacking image.

After that, the system control unit 48 determines whether or not all the plurality of image data obtained by focus stacking photography stored in the buffer area of the memory 33 have been read out (step S209).

Here, if it is determined that all the image data has not been read yet, the process goes to step S205 described above, the next image data is read, and the processing as described above is performed.

On the other hand, if it is determined in step S209 that all the image data have been read, the process returns.

According to the first embodiment as described above, the information of the photographing lens 2, the output contents of the system control unit 48 functioning as a focus position determination unit for focus stacking (focus position determination circuit for focus stacking), and the shooting distance. update the field angle range of the focus stacking image on the live view based on the effective focal length when displaying the live view and the effective focal length when the focus position is set to the far point, in response to at least one change in Since the angle of view of the focus stacking image generated by focus stacking photography is displayed as wide as possible before shooting, it is possible to uniquely check the angle of view.

This eliminates a disconcerting difference between the angle of view observed in live view before focus stacking shooting and the angle of view of the generated focus stacking image. becomes unnecessary, usability can be improved.

Also, because the maximum angle of view variation within the movable range of the focus position of the photographing lens 2 is determined, and the range of the angle of view of the focus stacking image based on the maximum angle of view variation is displayed on the live view. Since the size of the view angle limiting frame is fixed according to the type of the photographing lens 2 and does not change depending on the user's setting conditions, the user is provided with convenience that is easy to understand and easy to use. can give.

Furthermore, if you set the live view focus position near the far point focus position while waiting for the main focus stacking shooting, the view angle restriction frame for focus stacking shooting will no longer be displayed. There are advantages.

Then, for a lens group capable of depth stacking photography, the lens group maximum angle of view variation amount having the largest variation among the maximum angle of view variation amounts of the photographing lens 2 included in the lens group is determined. When the field angle range of the focus stacking image based on the lens group maximum field angle fluctuation amount for any of the photographic lenses 2 included in the group is displayed on the live view, the size of the field angle limit frame Since it does not change depending on the type of the photographing lens 2 and does not change depending on the user's setting conditions, it is possible to provide the user with convenience that is easier to understand and easier to use.

In addition, since the smaller one of the field angle range of the focus stacking image and the field angle range of the digital teleconverter magnification is displayed on the live view, multiple field angle ranges are displayed. It is possible to reduce the annoyance when it is done.

The processing of each unit described above may be performed by one or more processors configured as hardware. For example, each unit may be a processor configured as an electronic circuit, or may be each circuit unit in a processor configured with an integrated circuit such as an FPGA (Field Programmable Gate Array). Alternatively, a processor composed of one or more CPUs may read and execute a processing program recorded on a recording medium, thereby executing the function of each unit.

Further, although the above description has mainly focused on the imaging device, a control method for controlling the imaging device as described above may also be used. It may be a non-temporary recording medium readable by a computer for recording, or the like.

Furthermore, the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the present invention at the implementation stage. Moreover, various aspects of the invention can be formed by appropriate combinations of the plurality of constituent elements disclosed in the above embodiments. For example, some components may be omitted from all components shown in the embodiments. Furthermore, components across different embodiments may be combined as appropriate. As described above, it goes without saying that various modifications and applications are possible without departing from the gist of the invention.

DESCRIPTION OF SYMBOLS 1... Imaging device 2... Shooting lens 3... Camera body 21... Lens 22... Aperture 23... Shake correction optical element 24... Shake correction control unit 25... Aperture control unit 26... Lens control unit 27... Shake detection unit 28... Operation unit 29 Communication control section 30 Mechanical shutter 31 Imaging section 32 A/D conversion section 33 Memory 34 Image processing section 35 Imaging drive control section 36 Shutter control section 37 Lens communication section 38 Camera shake detection section 39 Exposure control unit 40 AF processing unit 41 Non-volatile memory 42 External memory 43 Display unit 43a Rear monitor 43b Electronic viewfinder 44 Operation unit 44a Release button 44b Front dial 44c Rear dial 44d Shooting mode Dial 44e...Cross button 44f...OK button 44g...AF button 44h...Information button 44i...Focus stacking button 44j...Movie button 44k...Enlarge button 45...Power control unit 46...Power supply unit 47...Flash unit 48...System control unit

Claims (7)

a photographing lens that forms an image of a subject and that has an effective focal length that changes according to the focus position;
an imaging unit that captures the subject image and outputs captured data;
a live view display unit that displays a live view based on the imaging data;
a focus stacking view angle range display unit that displays the view angle range of the focus stacking image on the live view;
a focus stacking focus position determination unit that determines and outputs a near point focus position and a far point focus position in focus stacking photography;
causing the imaging unit to repeatedly take images while moving the focus position of the imaging lens between the near point focus position and the far point focus position by a predetermined amount in the main photography of the focus stacking photography; an imaging control unit that outputs a plurality of imaging data;
a synthetic angle-of-view adjustment unit that adjusts the angle of view of each of the plurality of imaging data based on the effective focal length when each of the plurality of imaging data is captured;
a focus stacking unit configured to focus stack the plurality of imaging data whose angle of view has been adjusted by the composite view angle adjusting unit to generate the focus stacking image;
has
The focus stacking view angle range display unit displays the live view in accordance with a change in at least one of the information of the photographing lens, the output content of the focus stacking focus position determination unit, and the shooting distance. and updating the display of the angle-of-view range of the focus stacking image based on the effective focal length at the time and the effective focal length at the far point focus position. a photographing lens that forms an image of a subject and that has an effective focal length that changes according to the focus position;
an imaging unit that captures the subject image and outputs captured data;
a live view display unit that displays a live view based on the imaging data;
a focus stacking view angle range display unit that displays the view angle range of the focus stacking image on the live view;
a maximum angle of view fluctuation amount determination unit that determines a maximum angle of view fluctuation amount within a movable range of the focus position of the photographing lens based on the information of the photographing lens;
a focus stacking focus position determination unit that determines and outputs a near point focus position and a far point focus position in focus stacking photography;
causing the imaging unit to repeatedly take images while moving the focus position of the imaging lens between the near point focus position and the far point focus position by a predetermined amount in the main photography of the focus stacking photography; an imaging control unit that outputs a plurality of imaging data;
a synthetic angle-of-view adjustment unit that adjusts the angle of view of each of the plurality of imaging data based on the effective focal length when each of the plurality of imaging data is captured;
a focus stacking unit configured to focus stack the plurality of imaging data whose angle of view has been adjusted by the composite view angle adjusting unit to generate the focus stacking image;
has
the focus stacking view angle range display unit displays the view angle range of the focus stacking image based on the maximum view angle variation amount on the live view;
The composite angle-of-view adjustment unit adjusts the angle of view of each of the plurality of imaging data based on the angle-of-view range of the focus stacking image displayed on the live view before performing the actual photography of the focus stacking photography. An imaging device characterized by: further comprising a focus position setting unit that sets the focus position of the live view near the far point focus position determined by the focus stacking focus position determination unit in a state of waiting for the main photography of the focus stacking photography. The imaging device according to claim 1, characterized by: further comprising a focus stacking enable/disable determination unit that determines whether the focus stacking shooting is possible from the information of the shooting lens;
The maximum angle-of-view fluctuation amount determination unit determines the maximum angle-of-view fluctuation amount of the photographing lenses included in the lens group for a lens group composed of a plurality of photographing lenses determined to be capable of the focus stacking photographing. further determine the lens group maximum angle of view fluctuation amount with the largest fluctuation amount,
The focus stacking view angle range display unit displays the view angle range of the focus stacking image based on the lens group maximum view angle variation amount on the live view for any of the photographing lenses included in the lens group. 3. The imaging apparatus according to claim 2, wherein the image is displayed on the . further comprising a digital teleconverter setting unit for enlarging an image by limiting the angle of view of the imaging data based on a predetermined digital teleconverter magnification;
The focus stacking view angle range display unit displays the smaller view angle range of the view angle range of the focus stacking image and the view angle range of the digital teleconverter magnification on the live view. 3. The imaging device according to claim 1 or 2. an imaging step of imaging a subject image and outputting imaging data;
a live view display step of displaying a live view based on the imaging data;
a focus stacking angle of view range display step of displaying a range of view angle of the focus stacking image on the live view;
a focus stacking focus position determining step for determining and outputting a near point focus position and a far point focus position in focus stacking photography;
In the actual photographing of the focus stacking photographing, the imaging step while moving the focus position of the photographing lens that forms the subject image by a predetermined amount between the near point focus position and the far point focus position. an imaging control step for repeatedly imaging and outputting a plurality of imaging data;
a synthetic angle-of-view adjustment step of adjusting the angle of view of each of the plurality of image data based on the effective focal length of the photographing lens when each of the plurality of image data is captured;
a focus stacking step of generating the focus stacking image by stacking the plurality of image data whose angles of view have been adjusted by the synthetic view angle adjusting step;
has
The focus stacking view angle range display step displays the live view in accordance with a change in at least one of the information of the photographing lens, the output content of the focus stacking focus position determination step, and the shooting distance. and updating the display of the angle of view range of the focus stacking image based on the effective focal length at the time and the effective focal length at the far point focus position. an imaging step of imaging a subject image and outputting imaging data;
a live view display step of displaying a live view based on the imaging data;
a focus stacking angle of view range display step of displaying a range of view angle of the focus stacking image on the live view;
a maximum angle of view fluctuation amount determination step of determining a maximum angle of view fluctuation amount within a movable range of the focus position of the photographing lens based on information of the photographing lens that forms the subject image;
a focus stacking focus position determining step for determining and outputting a near point focus position and a far point focus position in focus stacking photography;
in the main photography of the focus stacking photography, repeatedly performing the imaging step while moving the focus position of the photography lens between the near point focus position and the far point focus position by a predetermined amount; an imaging control step for outputting a plurality of imaging data;
a synthetic angle-of-view adjustment step of adjusting the angle of view of each of the plurality of image data based on the effective focal length of the photographing lens when each of the plurality of image data is captured;
a focus stacking step of generating the focus stacking image by stacking the plurality of image data whose angles of view have been adjusted by the synthetic view angle adjusting step;
has
the focus stacking view angle range display step displays the view angle range of the focus stacking image based on the maximum view angle variation amount on the live view;
The synthetic angle-of-view adjusting step adjusts the angles of view of the plurality of imaging data based on the angle-of-view range of the focus stacking image displayed on the live view before the actual shooting of the focus stacking shooting. An imaging method characterized by:

Images