JP2019109271A - Imaging device - Google Patents

Abstract

To provide an imaging device that can achieve acceleration of photography only when high-speed photography is required, while preventing a deterioration in image quality during focus bracket photography.SOLUTION: An imaging device has an angle of view maintaining function to maintain a certain angle of view by controlling a zoom position in conjunction with a change in focus position, and a focus bracket photography function to continuously acquire a plurality of photographic images while changing the focus position on the basis of a photography condition set in advance by a photographer. The imaging device acquires information on a lens, and the total amount of movement of a zoom lens, the amount of movement changing from the start to the end of focus bracket photography, on the basis of a focus bracket photography condition set in advance by the photographer, and causes display means to display a zoom area in which the angle of view maintaining function can be applied to all images to be acquired in the focus bracket photography on the basis of the total amount of movement of the zoom lens.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an imaging apparatus having a function of holding an angle of view constant by performing zoom control simultaneously with focusing, and a focus bracket photographing function.

  Conventionally, when performing a focus operation by moving a focus lens, the angle of view of an object formed on the image forming surface of an imaging unit such as a CMOS sensor changes, and the current state appears as if a zoom operation was performed (pumping ) May occur. With respect to such a problem, Patent Document 1 proposes a technique for correcting so that the angle of view does not change by automatically moving the zoom lens when the focus lens moves. By using the above-described technique, it is not necessary to repeat the angle of view adjustment at the time of shooting many times.

  However, in Patent Document 1, there is a problem that the angle of view correction can not be performed quickly because it is necessary to control the motor for driving the zoom lens in order to correct the change in the angle of view. With respect to such a problem, Patent Document 2 introduces a technique for correcting a change in angle of view by electronic zoom. By using this technology, it is possible to realize rapid field angle correction.

  However, when the angle of view correction is performed using the electronic zoom, some of the types of lenses change the angle of view significantly, so the image quality is degraded by the electronic enlargement processing performed for the angle of view correction. there is a possibility. If there is sufficient time between focusing and shooting, and high-speed shooting is not required, it is ideal to correct the angle of view by optical zoom as much as possible. Usually, when taking a picture, it takes some time to perform a taking operation after focus adjustment, so the delay time due to the angle of view correction using the optical zoom is less likely to be a problem, and the optical zoom is used It is desirable to correct the angle of view.

  By the way, in recent years, a function called focus bracket photography has generally been mounted on an imaging apparatus. Focus bracket shooting is a function for shooting a plurality of images continuously while changing the focus position little by little when shooting.

  In Patent Document 3, a technology is introduced in which a plurality of images are continuously photographed while changing the focus position little by little, and an image having the best focusing state is selected and recorded among the plurality of photographed images. ing. By using this technology, it is possible to prevent acquisition of an image blurred due to defocusing in a situation where high precision focusing is required.

  Moreover, there is a technique called depth composition as a technique using focus bracket photography. For example, a subject such as a living insect is photographed continuously for several tens of times while changing the focus position, and only the in-focus areas of the photographed images are synthesized by post-processing. This is a technology to generate a composite image that matches. By using this technology, it is possible to combine an image in which the entire subject is in focus, even under shooting conditions where it is not possible to focus on the entire subject depending on conditions such as aperture setting conditions and subject distance. It is possible to generate.

Japanese Patent Laid-Open No. 6-250071 Japanese Patent Application Laid-Open No. 11-23949 JP 2004-135029 A

  However, when performing depth combination using focus bracket imaging, if the subject moves, a shift occurs in the combined image, and a composite image with a sense of discomfort may be generated. That is, since it is necessary to acquire all of the compositing source images while the subject does not move, high-speed shooting is required.

  An object of the present invention is to provide an imaging apparatus capable of realizing high-speed imaging only when high-speed imaging is required while suppressing deterioration in image quality.

In order to achieve the above object, the invention according to the present application is:
By controlling the zoom position in conjunction with the change of the focus position, a plurality of angle of view holding functions for keeping the angle of view constant and a plurality of focus positions are changed based on shooting conditions preset by the photographer. In an imaging apparatus provided with a focus bracket imaging function that continuously acquires captured images of
Based on the information on the lens and the focus bracket shooting conditions preset by the photographer, the total movement amount of the zoom lens changing from the start to the end of the focus bracket shooting is acquired, and Based on the present invention, the zoom unit to which the angle of view holding function can be applied is displayed on the display unit for all the images acquired during focus bracket imaging.

In the invention according to claim 2 of the present application, in the invention according to claim 1,
As information on the lens, information on a change in angle of view with respect to the zoom position and information on a change in angle of view with respect to the focus position are used.

In the invention according to claim 3 of the present application, in the invention according to claims 1 and 2,
A focus step and the number of shots are used as focus bracket shooting conditions.

The invention according to claim 4 of the present application is the invention according to any of claims 1 to 3.
The information related to the lens further includes information related to the current zoom lens position, and the angle of view holding function can be applied when the current zoom lens position exceeds the zoom area to which the angle of view holding function can be applied. A zoom lens position is moved within a zoom range.

  According to the present invention, when focus bracket shooting, high-speed shooting is required while suppressing deterioration in image quality by changing the zoom control method used for the angle of view holding function according to the length of total movement time. It is possible to realize speeding up of imaging only.

FIG. 1 is a schematic view showing a main configuration of a first embodiment according to the present invention. It is a flowchart showing the control method of a zoom lens when changing the focus position of 1st Embodiment based on this invention. It is a flowchart which shows the flow at the time of performing focus bracket imaging | photography of 1st Embodiment based on this invention. It is a flowchart which shows the flow for displaying the zoom range which can perform the focus bracket imaging | photography of 1st Embodiment based on this invention. It is an image figure at the time of displaying the zoom setting possible area | region of 1st Embodiment based on this invention on a display means. FIG. 6 is an explanatory diagram regarding a zoom control method when the position of the zoom lens according to the first embodiment is out of the zoom setting possible area according to the present invention.

First Embodiment
The first embodiment of the imaging apparatus according to the present invention will be described below.

  FIG. 1 is a schematic view showing the main configuration of a first embodiment of the imaging device according to the present invention. In this embodiment, an interchangeable lens system such as a single lens reflex camera is assumed, and for driving the zoom lens 101, a dedicated zoom lens driving device (hereinafter referred to as power zoom) mountable to the interchangeable lens is used. ing. The same control is possible even when the interchangeable lens and the power zoom are incorporated in the imaging apparatus, but the present embodiment will be described using the present system in which the delay due to the zoom control is large.

  First, the basic circuit configuration in the present embodiment will be described. In FIG. 1, 101 is a zoom lens, 102 is a focus lens, 103 is an imaging means, 104 is an image processing means, 105 is a display means, 106 is a camera CPU, 107 is a lens information storage means, and 108 is a focus bracket imaging condition setting means 109 is a lens CPU, 110 is a lens position detection means, 111 is a focus lens drive means, 112 is a zoom lens drive means, and 113 is a zoom operation means.

  Object light transmitted through the zoom lens 101 and the focus lens 102 is focused on the light receiving surface of the imaging unit 103, and an optical image formed is input to the imaging unit 103. The imaging unit 103 performs photoelectric conversion on the formed optical image, and generates an analog video signal inside the imaging unit 103. Furthermore, after converting an analog signal to a digital signal and performing digital signal processing such as gain processing by an ADC circuit in the imaging unit 103, a digital video signal is output as a final output from the imaging device. .

  The image processing means 104 can perform at least image enlargement processing and reduction processing on the input digital video signal, and although not described in detail in this embodiment, gain processing and white balance processing are also possible. , Γ correction, etc., having functions related to digital image processing. The image signal processed by the image processing unit 104 is displayed on the display unit 105. Also, it is possible to record an image on a recording unit (not shown).

  The camera CPU 106 performs system control of the entire imaging apparatus, and information stored in advance in the lens information storage unit 107, setting values set in the focus bracket photographing condition setting unit 108, and information from the lens CPU 109 The control of the zoom lens 101 for holding the angle of view constant is also performed. Further, the ratio calculation of the enlargement processing and the reduction processing of the image performed by the image processing unit 104 is also performed by the camera CPU 106. The control method of the details will be described later.

  The lens information storage unit 107 is provided with a look-up table (for each type of interchangeable lens (lens ID), information on the change in angle of view with respect to the position of the focus lens 102 and the zoom lens 101 and information on the moving speed of the lens). It is made to memorize beforehand as LUT). The moving speed of the lens is determined by the number of lenses, the mass based on the lens material and size, the type of motor for driving the lens, and the lens driving ability based on the supplied electric power, etc. The time required for the movement of the zoom lens 101 is acquired in advance as basic data, and table data is created based on the basic data, and is stored in advance as a LUT.

  The focus bracket shooting condition setting unit 108 is an input unit for the photographer to set the setting values of the focus step and the number of shot images when performing the focus bracket shooting. The setting value of the focus step represents the movement interval of the focus lens 102 among the plurality of images to be acquired, and each time an image is acquired, continuous imaging is performed while moving the focus lens 102 by the focus step. The focus lens 102 can be moved in either the close direction or the infinite direction, and the focus lens 102 can be moved in either direction by providing "+" and "-" signs to the setting value of the focus step. It can be moved.

  In this embodiment, “+” is an infinite direction, and “−” is a close direction. The number of shots is a setting value for determining how many consecutive shots are taken in one focus bracket shooting. That is, the total movement distance of the focus lens 102 in one focus bracket photographing can be known by the setting value of the focus step and the number of photographings set by the photographer.

  The camera CPU 106 reads the ratio of the change in the angle of view from the total movement distance of the focus lens 102 at the time of focus bracket photographing and the LUT related to the change in the angle of view accompanying the movement of the focus lens 102 stored in advance in the lens information storage unit 107. I can do it. Further, as to how much the zoom lens 101 should be moved in order to cancel out the change in the angle of view, reading is also made from the LUT related to the change in angle of view caused by the movement of the zoom lens 101 stored in the lens information storage unit 107. I can do it.

  The change in the angle of view accompanying the movement of the zoom lens 101 may be calculated from the ratio calculation between the target focal length and the current focal length. The camera CPU 106 moves the zoom lens 101 via the lens CPU 109, or performs electronic enlargement / reduction processing by the image processing unit 104 to hold the angle of view constant even when the focus lens 102 is moved. I can do it.

  The lens CPU 109 can read out information on the type of lens (lens ID) from the lens ID storage unit (not shown), and transmits the read lens ID to the camera CPU 106, so that the camera CPU 106 holds an accurate angle of view. It is possible to realize In addition, the lens CPU 109 can detect the position information of the zoom lens 101 and the focus lens 102 using the lens position detection unit 110, and transmits the latest position information to the camera CPU 106 as necessary. Can do.

  Further, it is also possible to drive the zoom lens 101 and the focus lens 102 in accordance with an instruction from the camera CPU 106. When the focus lens 102 is driven, the focus lens drive unit 111 is used to drive the focus lens 102. When the zoom lens 101 is driven, the zoom lens drive unit 112 within the power zoom is used to drive the zoom lens 101. Drive the

  The zoom operation means 113 is an operation means used when the photographer performs zooming using a power zoom, and the lens CPU 109 moves the zoom lens 101 to the wide angle side when the photographer instructs the wide angle side. When an instruction to the telephoto side is issued, the lens CPU 109 moves the zoom lens 101 to the telephoto side.

  The basic circuit configuration has been described above, but this configuration is an example of the minimum configuration necessary to realize the zoom control method described in this embodiment, and the circuit configuration is not limited to this. . Further, as described above, the system is not necessarily the system of the interchangeable lens system, and all control may be performed only in the imaging device.

  Hereinafter, a specific zoom control method when the focus position is changed during focus bracket shooting will be described. First, the concept of zoom control in the present embodiment will be described.

  In this embodiment, focus bracket shooting condition setting parameters set by the photographer, that is, the setting of the focus step and the number of shots, and the type of interchangeable lens acquired from the lens CPU 109, that is, information on the change of the angle of view with respect to the lens position Based on information on the moving speed of the zoom lens 101, the total moving time of the zoom lens 101 required from the start to the end of focus bracket shooting is calculated, and the optical zoom and the electron are calculated according to the total moving time. Switch the zoom.

  Specifically, when the total movement time of the zoom lens 101 is 500 [ms] or more, priority is given to simultaneousness of shooting, and electronic angle zoom is performed using electronic zoom in order to speed up shooting. If the total moving time of the zoom lens 101 is shorter than 500 ms, priority is given to the image quality (resolution), and the angle of view is held using the optical zoom.

  FIG. 2 is a flowchart showing a control method of the zoom lens 101 when the focus position is changed. In this flowchart, description will be made including a determination as to whether or not the angle of view holding function and the focus bracket photographing function are enabled. Further, in the present embodiment, since a system using an interchangeable lens and a power zoom is assumed, originally, a flow for checking the mounting state of the interchangeable lens and the power zoom is also necessary. And since the drive itself of the zoom lens 101 can not be performed, the description will be made on the premise that both are mounted.

  At S200, a flow for determining the control method of the zoom lens 101 when changing the focus position is started. In S201, it is determined whether the angle-of-view holding function is activated. If it is determined in the flow of S201 that the angle of view holding function is not activated, the process proceeds to S214, and the angle of view change accompanying the change of the focus position is set not to be corrected by the zoom control. If it is determined in the flow of S201 that the angle of view holding function is activated, the process proceeds to S202.

  In S202, communication is performed between the camera CPU 106 and the lens CPU 109, and the type of interchangeable lens (lens ID) is acquired. By acquiring the lens ID, it is possible to acquire the rate of change of the angle of view accompanying the movement of the zoom lens 101 and the focus lens 102 from the information (LUT) stored in advance in the lens information storage unit 107. After acquiring the lens ID in S202, the process proceeds to S203.

  In step S203, it is determined whether the focus bracket shooting function is enabled. If it is determined that the focus bracket shooting function is enabled, the process proceeds to step S204. If it is determined that the focus bracket photographing function is not activated, the process advances to step S213, and it is determined that the change in the angle of view accompanying the change in the focus position is corrected using the optical zoom.

  In S204, the setting value of the focus step set by the focus bracket photographing condition setting means 108 is acquired. In the present embodiment, it is assumed that the setting value of the focusing step is -10 [step]. The sign “−” attached to the setting value of the focus step indicates that the focus lens 102 is moved in the close direction, as described above. The setting of the focusing step does not necessarily coincide with the number of steps of the motor. However, in the present embodiment, for the convenience of explanation, the moving accuracy of the focusing lens 102 will be described in units of [step]. After acquiring the setting value of the focus step, the process proceeds to S205.

  In S205, the setting value of the number of shot images at the time of focus bracket shooting, which is set by the focus bracket shooting condition setting unit 108, is acquired. In the present embodiment, it is assumed that the number of captured images is 30. After acquiring the set value of the number of shots, the process proceeds to S206.

  In S206, the total movement amount of the focus lens 102 by focus bracket photography is calculated. Since the total movement amount of the focus lens 102 can be calculated by: focus step × number of shots, in this embodiment, −10 [step] × 29 [sheets] = − 290 [step] is the total movement amount of the focus lens 102 It becomes. That is, the focus lens 102 is moved in the close direction by 290 [steps] at the time of focus bracket shooting. After calculating the total movement amount of the focus lens 102, the process proceeds to S207.

  In S207, the current positions of the focus lens 102 and the zoom lens 101 are detected, and the lens CPU 109 transmits these pieces of information to the camera CPU 106. After transmitting the position information of the focus lens 102 and the zoom lens 101, the process proceeds to S208.

  In S208, the information on the lens ID acquired in the flow of S202, the information on the total movement amount of the focus lens 102 calculated in the flow of S206, and the position information of the current focus lens 102 acquired in the flow of S207 At the time of focus bracket photographing, the angle of view change rate when the focus position is changed is read from the LUT related to the angle of view change with respect to the position of the focus lens 102 stored in the lens position information storage unit. In this embodiment, it is assumed that the change rate of the angle of view accompanying the change of the focus position is 0.80. After acquiring the rate of change of the angle of view accompanying the change of the focus position, the process proceeds to S209.

  In S209, based on the information on the lens ID acquired in the flow of S202, the position information of the current zoom lens 101 acquired in the flow of S207, and the information of the rate of change of angle of view acquired in the flow of S208. The total movement amount of the zoom lens 101 necessary to cancel the change of the angle of view accompanying the change of the focus position is read from the LUT regarding the change of the angle of view with respect to the zoom position.

  In this embodiment, in order to keep the angle of view from the start to the end of focus bracket shooting, the zoom lens 101 is moved so as to finally become 1.25 (1 / 0.80) times. There must be. In this embodiment, it is assumed that the total moving amount of the zoom lens 101 for keeping the angle of view is +100 [step]. After acquiring the total movement amount of the zoom lens 101, the process proceeds to S210.

  In S210, the time required to move +100 [step] which is the total movement amount of the zoom lens 101 is calculated. The total movement time of the zoom lens 101 can be calculated by the total movement amount of the zoom lens 101 × the zoom lens movement speed, and the zoom lens movement speed is stored in advance in the lens position information storage unit as described above. ing. It is assumed that the lens used in the present embodiment has a zoom lens moving speed of 3 ms / step. That is, the total moving time of the zoom lens 101 is | −100 [step] | × 3 [ms / step] = 300 [ms]. After calculating the total moving time of the zoom lens 101, the process proceeds to S211.

  In S211, it is determined whether the total moving time of the zoom lens 101, that is, the focus bracket photographing time is equal to or more than a threshold. In the present embodiment, the threshold is 500 [ms]. If it is determined that the focus bracket shooting time is equal to or greater than the threshold, the process advances to step S212, and it is determined that the change in the angle of view accompanying the change in the focus position is corrected using the electronic zoom. If it is determined that the length is shorter than the threshold, the process advances to step S213, and it is determined to correct the change in the angle of view accompanying the change in the focus position using the optical zoom.

  In the present embodiment, since the total movement time of the zoom lens 101 calculated in S210 is 300 ms, it is determined to be shorter than the threshold 500 ms, and the angle of view change with the change in focus position. To be corrected using an optical zoom.

  As described above, when the total movement time of the zoom lens 101 required from the start to the end of focus bracket shooting is equal to or greater than the threshold, the change of the angle of view accompanying the change of the focus position is made using the electronic zoom By performing the correction, it is possible to speed up imaging, and it is possible to improve the simultaneousness of a plurality of images acquired by continuous imaging.

  In addition, when the total movement time of the zoom lens 101 is shorter than the threshold, the simultaneousness of a plurality of images acquired by continuous shooting is easily maintained, so the change of the angle of view accompanying the change of the focus position is made using the optical zoom. It is possible to suppress the deterioration of the image quality by correcting the correction.

  In the present embodiment, the method of correcting the angle of view change accompanying the change of the focus position is determined by the threshold of 500 [ms], but it is also possible to change according to the subject to be photographed. When the movement of the subject is large, it is difficult to maintain the simultaneousness of a plurality of shootings, so high-speed shooting is required. For example, the size of the movement of the subject may be detected using a technique such as detection of a motion vector, the determination threshold may be lengthened if the movement is small, and the determination threshold may be shortened if the movement is large. Also, the photographer may be allowed to change the determination threshold on the UI, or the photographer may be forced to set the optical zoom and the electronic zoom.

  Subsequently, a flow of performing focus bracket imaging will be described with reference to the flowchart of FIG. At S300, the focus bracket imaging flow is started. In S301, it is determined whether a shooting operation of focus bracket shooting has been performed. If it is determined that the photographing operation has not been performed, the process returns to the flow of S301. If it is determined that the photographing operation has been performed, the process proceeds to step S302. In S302, the first image is acquired, and the process proceeds to S303. In step S303, the number of remaining shots for focus bracketing is reduced by one.

  In S304, it is determined whether or not the number of remaining shot images for focus bracket shooting is zero. If the number of remaining shots is zero, the process advances to step S313 to end focus bracket shooting, and then returns to the flow of step S301. If the remaining number of shots is not zero, the process advances to step S305.

  In step S305, information related to the change in the angle of view with respect to the focus position stored in advance in the lens bracket stored in the lens information storage unit 107, the setting value of the focus step set by the focus bracket photographing condition setting unit 108, the lens ID From LUT, it is acquired how much the ratio of the angle of view at the time of the next focus bracket photographing changes with respect to the current angle of view. After acquiring the angle-of-view change rate, the process advances to step S306.

  In S306, when performing focus bracket shooting, which of the optical zoom and the electronic zoom is used to change the angle of view accompanying the change of the zoom position, that is, the result of the zoom control method determined in the flow of FIG. Do. In the case of correcting the angle of view using the optical zoom, the process proceeds to S307, and in the case of correcting the angle of view using the electronic zoom, the process proceeds to S310.

  In step S307, based on the rate of change in angle of view acquired in the flow of step S305, the amount of movement of the zoom lens 101 for canceling the change in angle of view associated with the change in focus position is information related to the change in angle of view with respect to the zoom position (LUT) Get from After acquiring the movement amount of the zoom lens 101, the process proceeds to S308.

  In step S308, the position of the zoom lens 101 is moved by the movement amount of the zoom lens 101 acquired in the flow of step S307. After moving the position of the zoom lens 101, the process proceeds to S309. In S309, image acquisition is performed at the zoom position moved in the flow of S308. After the image acquisition, the flow returns to S303 again. In S310, based on the angle-of-view change rate acquired in the flow of S305, the enlargement / reduction ratio of the image at the time of performing the electronic zoom process on the acquired image is calculated. After calculating the scaling factor of the image, the process proceeds to S311. In step S311, only the focus position is changed by the focus step, and image acquisition is performed. After acquiring the image, the process proceeds to S312. In step S312, the electronic zoom processing is performed on the image acquired in the flow of step S311 for the image scaling factor calculated in step S310. After performing the electronic zoom processing, the flow returns to the flow of S303 again.

  As described above, by using the above-described flow, it is possible to perform focus bracket imaging while correcting a change in angle of view accompanying a change in focus position using an appropriate zoom control method.

  However, the above-described focus bracket imaging method has problems. Specifically, when focus bracket shooting is started with the current zoom position close to the mechanical end, the zoom lens 101 collides with the mechanical end halfway, and the angle of view is constant for all images acquired It may not be possible to keep holding. In other words, if the zoom position at the time of starting the focus bracket shooting is within which range, the photographer does not know that the desired focus bracket shooting can be performed.

  In order to solve the above problems, in the present embodiment, the change of the angle of view with respect to the lens ID acquired from the lens CPU 109, the focus bracket photographing conditions set by the photographer, and the position of the lens stored in the lens information storage unit 107 in advance. A method of displaying a zoom range in which desired focus bracket shooting can be performed from information on the rate will be described. Here, what is desired is that a constant angle of view is kept for all images acquired during focus bracket imaging.

  FIG. 4 is a flowchart showing a flow for displaying a zoom range in which focus bracket imaging can be performed. At S400, a flow for displaying a zoom range in which focus bracket shooting can be performed is started. Since the flow of S401 is the same as the flow of S202, the description will be omitted. Since the flow of S402 is also the same as the flow of S203, the description will be omitted. However, if it is determined that the focus bracket shooting function is not activated, the process proceeds to step S413.

  In S413, the zoom area at the time of normal shooting is displayed. FIG. 5A shows the zoom area at the time of normal shooting. In the figure, a rectangular white area indicates the zoom setting area, and a rectangular gray area indicates the zoom setting impossible area. Also, the mark of the inverted triangle represents the current zoom position, the left side is the wide angle side, and the right side is the telephoto side. The position described as the mechanical end is the physical end on the wide-angle side and the telephoto side. As shown in FIG. 5A, it is possible to set the zoom area at the time of normal shooting up to the mechanical end on both the wide-angle side and the telephoto side. After the zoom area shown in FIG. 5A is displayed on the display unit 105 in the flow of S413, the process proceeds to S414. The flow of S403 to S407 is the same as the flow of S204 to S208, so the description will be omitted.

  In S408, the reference position of the zoom lens 101 at the time of reading the total movement amount of the zoom lens 101 from the LUT relating to the change in the angle of view with respect to the zoom position is considered with the mechanical end as the reference position. The reason is that the final image does not exceed the mechanical end among the images acquired in the focus bracket shooting, so the zoom setting may be made such that the final image is just the mechanical end. Whether the mechanical end which is the reference position is set to the wide-angle end or the telephoto end depends on whether the setting of the focus step is “+” or “−”. When the setting of the focus step is “−”, the focus lens 102 moves in the close direction, so the zoom lens 101 moves to the telephoto side to maintain the angle of view.

  In that case, the reference position when acquiring the amount of movement of the focus lens 102 may be the mechanical end on the telephoto side. When the setting of the focus step is "+", the reference position may be set to the mechanical end on the wide-angle side. After acquiring the total moving amount of the zoom lens 101 at S408, the process proceeds to S409.

  In S409, a zoom settable area in which focus bracket shooting can be performed is acquired. For example, as in FIG. 2, when the setting of the focus step is “−” and the angle of view change rate accompanying the change of the focus position is 0.8 times, the angle of view is corrected to 1.25 times by zoom control. There must be. If the zoom position at the start of focus bracket shooting is at a zoom position where the angle of view is 0.8 or less with respect to the telephoto end, the angle of view can be maintained for all acquired images. That is, it is preferable to set the zoom settable area as the entire zoom range side of the zoom position at which the angle of view is 0.8 times with respect to the telephoto end. When the setting of the focus step is "+", the opposite is true. After acquiring the zoom settable area, the process proceeds to S410.

  In S410, the zoom setting possible area acquired in S409 is displayed on the display unit 105. An example is shown in FIGS. 5 (b) and 5 (c). FIG. 5B shows the zoom setting possible area when the setting of the focus step is “−”. The T end moves to the T ′ end, and an extra zoom area for compensating for the change in angle of view to the telephoto side is secured. Further, FIG. 5C shows the zoom setting possible area when the setting of the focus step is “+”. The W end moves to the W 'end, and an extra zoom area is secured for correcting the change in angle of view to the wide angle side. After displaying the zoom settable area, the process proceeds to step S411.

  In S411, it is determined whether the current position of the zoom lens 101 is out of the zoom setting possible area. If it is not determined that the area is outside the zoom setting possible area, the process proceeds to S414. If it is determined that the zoom lens 101 is out of the zoom settable area, the process proceeds to step S412. The position of the zoom lens 101 is forcibly moved to be within the zoom settable area, and then the process proceeds to step S414.

  This flow will be briefly described with reference to FIG. If the current zoom position is at the position shown in FIG. 6A at the time of the flow of S411, the process proceeds to S412, and the current zoom position is moved to the position of FIG. 6B. By doing so, even if focus bracket imaging is started, it is possible to keep holding a constant angle of view for all the acquired images.

  In S414, it is determined whether the photographing start operation has been performed by the photographer. If the shooting start operation has been performed, the process advances to step S415 to start focus bracket shooting. If the shooting start operation has not been performed, the process returns to step S402.

  As described above, the imaging unit 105 causes the display unit 105 to display, as the zoom settable region, a zoom area in which a constant angle of view can be maintained for all images acquired during focus bracket imaging. Before the user starts focus bracketing, it is possible to confirm whether the desired imaging is possible.

101: Zoom lens 102: Focus lens 103: Imaging means 104: Image processing means 105: Display means 106: Camera CPU
107... Lens information storage means 108... Focus bracket photographing condition setting means 109 .. Lens CPU
110 Lens position detection means 111 Focus lens drive means 112 Zoom lens drive means 113 Zoom operation means

Claims (4)

By controlling the zoom position in conjunction with the change of the focus position, a plurality of angle of view holding functions for keeping the angle of view constant and a plurality of focus positions are changed based on shooting conditions preset by the photographer. In an imaging apparatus provided with a focus bracket imaging function that continuously acquires captured images of
Based on the information on the lens and the focus bracket shooting conditions preset by the photographer, the total movement amount of the zoom lens changing from the start to the end of the focus bracket shooting is acquired, and Based on the present invention, the zoom unit to which the angle of view holding function can be applied is displayed on the display unit for all the images acquired during focus bracket imaging. In the invention according to claim 1,
As information on the lens, information on a change in angle of view with respect to the zoom position and information on a change in angle of view with respect to the focus position are used. In the invention according to claim 1 or 2,
A focus step and the number of shots are used as focus bracket shooting conditions. In the invention according to any one of claims 1 to 3,
The information related to the lens further includes information related to the current zoom lens position, and the angle of view holding function can be applied when the current zoom lens position exceeds the zoom area to which the angle of view holding function can be applied. A zoom lens position is moved within a zoom range.