JP2023026997A - Imaging device, imaging method, program, and recording medium - Google Patents

Abstract

To solve a problem in which coloring and saturation may not occur when the exposure is changed and the exposure is corrected in omnifocal imaging.SOLUTION: An imaging device according to the present invention includes determination means for determining a predetermined value of exposure in advance, imaging means for imaging a plurality of images with different focus positions, control means for controlling such that when the imaging means captures the plurality of images, the images are captured with an exposure lower than the predetermined value, and correction means for correcting the brightness of at least a part of the plurality of images on the basis of the predetermined value determined by the determination means.SELECTED DRAWING: Figure 4

Description

The present invention relates to an image pickup apparatus capable of omnifocal image pickup that takes images at a plurality of focus positions.

2. Description of the Related Art Imaging apparatuses that perform omnifocal imaging are conventionally known. All-in-focus imaging is imaging a plurality of images with different focal positions over the entire range of object distances that can be focused by an imaging device (Patent Document 1). A deeper depth of field than the original image, in which only the in-focus area is extracted from multiple images obtained by omnifocal imaging and the entire imaging area is in focus by synthesizing a single image. The technique for generating images is called depth stacking.

In addition, it is known that in all-focus imaging, the brightness changes between the acquired images due to various factors. For example, Patent Literature 2 discloses that the brightness of an image changes due to a change in the effective F-number in all-focus imaging. FIG. 7 is a diagram for explaining an example of the relationship between the focus position and the change in the effective F-number in omnifocal imaging. Also, FIG. 8 is a diagram for explaining an example of the relationship between the focus position and the change in luminance value in omnifocal imaging. As shown in FIGS. 7 and 8, there may be a difference in brightness between images in omnifocal imaging.

In addition, it is known that omnifocal imaging using a strobe and omnifocal imaging using a high-speed shutter also cause changes in brightness.

When merging a plurality of images, if there is a change in brightness in the plurality of images, unevenness in brightness may occur in the synthesized image. In order to avoid unevenness in the brightness of the synthesized image, it is desirable to correct the brightness of each image to be used for synthesis after acquiring the images.

JP-A-10-290389 JP 2020-107956 A

However, in a scene in which the brightness is corrected in the direction of darkening, there may occur a problem that the high-brightness portion of the image is colored, or a problem that saturation does not occur.

The above problems will be explained with reference to the drawings. FIG. 12 is a diagram showing a gamma curve when converting RAW into YUV. When the RAW luminance value 1201 shown on the horizontal axis is exceeded, the YUV luminance value becomes the upper limit value 1202 . For example, if the maximum value of RAW drops to a luminance value of 1203 when correcting to darken the brightness, the upper limit value of YUV luminance becomes a luminance value of 1204, and saturation does not occur. Further, when the brightness is lowered in a portion where the RAW luminance value is close to saturation, the ratio of the red or blue pixels to the RAW green pixel changes, resulting in coloring of the high luminance portion.

As described above, in a scene in which the brightness is corrected to be darkened, even if the brightness is corrected to be the same, there is a problem that the omnifocal image shows coloring and a difference in brightness.

In order to solve the above-mentioned problems, the present invention provides a determination means for determining a predetermined exposure value in advance, an imaging means for capturing a plurality of images with different focus positions, and a , a control means for controlling the imaging with an exposure lower than the predetermined value; and a correcting means for correcting the brightness of at least a part of the plurality of images based on the predetermined value determined by the determining means. and an imaging device characterized by comprising:

According to the configuration of the present invention, it is possible to generate a good composite image in which coloring and unevenness in brightness are suppressed.

1 is a block diagram showing the structure of a digital camera according to an embodiment of the present invention; FIG. 4 is a flowchart for explaining generation of a composite image according to the first embodiment of the present invention; 4 is a flowchart for explaining imaging in the first embodiment of the present invention; 4 is a flowchart for explaining brightness correction according to the first embodiment of the present invention; 4 is a flow chart for explaining alignment in the first embodiment of the present invention; 4 is a flowchart for explaining image synthesis in the first embodiment of the present invention; FIG. 10 is a diagram for explaining a luminance change in the case of driving the diaphragm when the luminance value changes due to the change of the focus position; FIG. 5 is a diagram for explaining luminance changes when driving the diaphragm in the first embodiment of the present invention; FIG. 10 is a flow chart for explaining synthesizing of synthesized images according to the second embodiment of the present invention; FIG. FIG. 10 is a diagram for explaining an example of the relationship between the focus position and the effective F-number change in omnifocal imaging; FIG. 10 is a diagram for explaining an example of the relationship between a focus position and a change in luminance value in omnifocal imaging; FIG. 4 is a diagram showing a gamma curve when converting RAW to YUV; FIG. 10 is a diagram for explaining how luminance changes due to uneven light emission or uneven exposure when capturing a plurality of images according to the present invention;

Preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

(First embodiment)
FIG. 1 is an example of a block diagram showing the structure of a digital camera as an image processing apparatus according to this embodiment. The digital camera 100 can capture a plurality of still images while changing the focus position.

The control unit 101 is, for example, a signal processor such as a CPU or MPU, and controls each part of the digital camera 100 while reading out a program stored in advance in a ROM 105, which will be described later. For example, as will be described later, the control unit 101 issues commands to the imaging unit 104, which will be described later, regarding the start and end of imaging. Alternatively, based on a program stored in the ROM 105, an image processing command is issued to the image processing unit 107, which will be described later. A user's command is input to the digital camera 100 by an operation unit 110 (to be described later) and reaches each part of the digital camera 100 through the control unit 101 .

The drive unit 102 is configured by a motor or the like, and mechanically operates an optical system 103 to be described later under a command from the control unit 101 . For example, based on a command from the control unit 101 , the drive unit 102 moves the position of the focus lens included in the optical system 103 to adjust the focal length of the optical system 103 .

The optical system 103 is composed of a zoom lens, a focus lens, an aperture, and the like. A diaphragm is a mechanism that adjusts the amount of light that is transmitted. By changing the position of the lens, the focus position can be changed.

The imaging unit 104 is a photoelectric conversion element that performs photoelectric conversion to convert an incident optical signal into an electrical signal. For example, a CCD sensor, a CMOS sensor, or the like can be applied to the imaging unit 104 . The imaging unit 104 has a moving image capturing mode, and can capture a plurality of temporally continuous images as each frame of a moving image.

The ROM 105 is a read-only non-volatile memory as a recording medium, and stores the operation program of each block provided in the digital camera 100 as well as the parameters required for the operation of each block. A RAM 106 is a rewritable volatile memory, and is used as a temporary storage area for data output during operation of each block of the digital camera 100 .

The image processing unit 107 performs various image processing such as white balance adjustment, color interpolation, and filtering on the image output from the imaging unit 104 or image signal data recorded in a built-in memory 109, which will be described later. . Also, the data of the image signal captured by the imaging unit 104 is subjected to compression processing according to a standard such as JPEG.

The image processing unit 107 is composed of an integrated circuit (ASIC) that is a collection of circuits that perform specific processing. Alternatively, the control unit 101 may perform processing according to a program read from the ROM 105 so that the control unit 101 may share some or all of the functions of the image processing unit 107 . If the control unit 101 shares all the functions of the image processing unit 107, the image processing unit 107 does not have to be provided as hardware.

A display unit 108 is a liquid crystal display, an organic EL display, or the like for displaying images temporarily stored in the RAM 106, images stored in a built-in memory 109, which will be described later, or setting screens of the digital camera 100. be.

The built-in memory 109 is a place for recording an image captured by the image capturing unit 104, an image processed by the image processing unit 107, information on a focus position at the time of image capturing, and the like. A memory card or the like may be used instead of the built-in memory.

The operation unit 110 is, for example, buttons, switches, keys, mode dials, etc. attached to the digital camera 100, or a touch panel that is also used as the display unit 108, or the like. A command from the user reaches the control unit 101 via the operation unit 110 .

FIG. 2 is a flowchart for explaining generation of a composite image according to this embodiment.

In step S201, the imaging unit 104 captures a plurality of images with different focus positions. In this embodiment, the imaging unit 104 performs imaging while changing the focus position from the close-up side to the infinity side.

In step S202, the control unit 101 and the image processing unit 107 correct the brightness of the multiple images captured by the imaging unit 104 in step S201.

In step S203, the control unit 101 and the image processing unit 107 align the plurality of images after brightness correction in step S202.

In step S204, the control unit 101 and the image processing unit 107 combine the images after alignment in step S203 to generate a combined image. Each step will be described in detail below.

FIG. 3 is a flowchart for explaining imaging in step S201 in this embodiment.

In step S301, the control unit 101 sets the focus position. For example, the user designates a focus position through the touch panel also used by the display unit 108, and designates a plurality of focus positions at equal intervals before and after the focus position corresponding to the designated focus position in the optical axis direction. At the same time, the control unit 101 determines the imaging order in order of distance at the set focus position.

In step S302, the control unit 101 determines exposure conditions for imaging. The control unit 101 determines shutter speed, F-number, and ISO sensitivity. The exposure conditions may be set manually by the user, or may be set automatically by the control unit 101 causing the imaging unit 104 to measure the subject.

In step S303, the control unit 101 calculates the amount of exposure darker than the exposure condition (predetermined value of exposure) defined in step S301 (the amount of exposure reduction). The amount of exposure reduction may be determined, for example, by the performance of the lens attached to the optical system 103 . Since how much the effective F-number changes depending on the amount of change in the focus position depends on the lens performance, for example, the amount of change in the effective F-number when moving the focus position from the closest point to infinity is used as the amount of exposure reduction. can handle. Also, when using a strobe, the amount of exposure reduction should be determined in consideration of the strobe's performance, including unevenness in light emission, and when using a high-speed shutter, the amount of exposure reduction should be determined in consideration of shutter performance, including exposure unevenness. It is also recommended to decide At least one of the shutter speed, F number, and ISO sensitivity may be used as the amount of exposure reduction.

In step S304, the control unit 101 moves the focus to an unimaged focus position among the focus positions set in step S301 in accordance with the imaging order determined in step S301.

In step S305, the imaging unit 104 performs imaging by darkening the exposure determined in step S302 by the exposure determined in step S303.

In step S306, the control unit 101 determines whether or not imaging has been performed at all the focus positions set in step S301. If the image has been captured at all the focus positions, the processing in this flow chart ends, and if there is a focus position that has not been captured yet, the process returns to step S304.

In the flowchart shown in FIG. 3, while the imaging unit 104 is capturing a plurality of images, the control unit 101 does not change settings for imaging, including exposure, other than the focus position. As described above, the brightness of the image changes simply by changing the focus position.

FIG. 4 is a flowchart for explaining brightness correction in step S202 in this embodiment.

In step S401, the control unit 101 acquires an image to be subjected to brightness correction from among the images captured by the imaging unit 104 in step S201. The target image for brightness correction is the image that has the earliest imaging order among the images that have not yet become the target image for brightness correction, other than the first image captured first.

In step S402, the control unit 101 acquires a reference image for brightness correction from among the images captured by the imaging unit 104 in step S201. A reference image for brightness correction is an image captured before the target image.

In step S403, the control unit 101 calculates the brightness ratio between the reference image and the target image. As a calculation method, for example, it is preferable to obtain by comparing the integrated values of green pixels in the RAW images of the reference image and the target image. You can look and compare.

In step S404, the control unit 101 calculates a cumulative gain amount by accumulating the brightness ratio obtained in step S403. The cumulative gain amount is obtained by multiplying the gain amount obtained before the current reference image and the target image by the ratio obtained in step S403 this time, so that the brightness of the target image is obtained by the exposure determined in step S302. is a value for approximating

In step S405, the control unit 101 associates the cumulative gain amount obtained in step S404 with the target image. It is desirable to store combinations of cumulative gain amounts and target images in the RAM 106 in the form of an array.

In step S406, the control unit 101 determines whether all images have been processed. If all images have been processed, proceed to step S407; otherwise, return to step S401.

In step S407, the image processing unit 107 uniformly corrects brightness in the image plane by the cumulative gain associated in step S405 for all images other than the first image captured first. . The brightness may be corrected in the RAW state after sensor output, in the conversion from RAW to YUV, or in the RGB state.

FIG. 5 is a flowchart for explaining alignment in step S203 in this embodiment.

In step S501, the control unit 101 acquires a reference image for alignment from among the images captured by the imaging unit 104 in step S201. Assume that the reference image for alignment has the earliest imaging order. Alternatively, since the angle of view slightly changes between captured images by capturing images while changing the focus position, the angle of view may be the narrowest among the captured images.

In step S502, the control unit 101 acquires a target image for alignment processing. It is assumed that the target image is an image other than the reference image acquired in step S501 and has not been subjected to alignment processing. If the control unit 101 sets the image with the earliest imaging order as the reference image, the control unit 101 may sequentially acquire the target images in the imaging order.

In step S503, the control unit 101 calculates the positional deviation amount between the reference image and the target image. An example of the calculation method is described below. First, the control unit 101 sets a plurality of blocks in the reference image. Control unit 101 preferably sets the size of each block to be the same. Next, the control unit 101 sets a search range that is wider than the blocks of the reference image at the same positions as the respective blocks of the reference image in the target image. Finally, the control unit 101 calculates a corresponding point in each search range of the target image that has the minimum sum of absolute differences in luminance (Sum of Absolute Difference, hereinafter referred to as SAD) from the block of the reference image. . The control unit 101 calculates the positional deviation in step S503 as a vector from the center of the block of the reference image and the corresponding point described above. In calculating the corresponding points described above, the control unit 101 uses the sum of squared differences (hereinafter referred to as SSD), normalized cross correlation (hereinafter referred to as NCC), etc. in addition to SAD. may

In step S504, the control unit 101 calculates a transform coefficient from the amount of positional deviation between the reference image and the target image. The control unit 101 uses, for example, a projective transform coefficient as the transform coefficient. However, the transform coefficients are not limited to projective transform coefficients, and affine transform coefficients or simplified transform coefficients with only horizontal and vertical shifts may be used.

In step S505, the image processing unit 107 transforms the target image using the transform coefficients calculated in step S504.

For example, the control unit 101 can transform using the formula shown in (Formula 1).

In (Equation 1), (x', y') indicate coordinates after deformation, and (x, y) indicate coordinates before deformation. Matrix A indicates the deformation coefficients calculated by the control unit 101 in step S404.

In step S506, the control unit 101 determines whether alignment has been performed for all images other than the reference image. If all the images other than the reference image have been aligned, the processing in the flowchart shown in FIG. 5 ends.

Further, when aligning a plurality of images captured by the above-described multi-lens camera, the amount of parallax caused by the difference in the position of the optical system 103 can be obtained by calculating the amount of deviation in step S503. Alignment can be done.

FIG. 6 is a flowchart for explaining image composition in step S204 in this embodiment.

In step 601, the image processing unit 107 calculates a contrast value for each image (including the reference image) after alignment. As an example of a method of calculating the contrast value, for example, first, the image processing unit 107 calculates the luminance Y from the color signals Sr, Sg, and Sb of each pixel using the following (Equation 2).
Y=0.299Sr+0.587Sg+0.114Sb (Formula 2)

Next, a contrast value I is calculated using a Sobel filter on the matrix L of luminance Y of 3×3 pixels, as shown in (Equation 3) to (Equation 5) below.

Further, the method of calculating the contrast value described above is merely an example. For example, it is also possible to use an edge detection filter such as a Laplacian filter or a bandpass filter that passes a predetermined band as the filter to be used.

In step S602, the image processing unit 107 generates a synthetic map. As a method of generating a synthesis map, the image processing unit 107 compares the contrast values of pixels at the same position in each image and calculates a synthesis ratio according to the magnitude of the contrast values.

An example of a specific calculation method is shown below.

A synthetic map Am(x, y) is generated using the contrast value Cm(x, y) calculated in step S601. Note that m is the m-th image among a plurality of images with different focus positions, x is the horizontal coordinate of the image, and y is the vertical coordinate. As a method of generating a synthesis map, the image processing unit 107 compares the contrast values of pixels at the same position in each image and calculates a synthesis ratio according to the magnitude of the contrast values. Specifically, among the images at the same position, the pixel with the largest contrast value is given a 100% synthesis ratio, and the other pixels at the same position are given a 0% synthesis ratio. That is, the following (Equation 6) holds.

However, in step S602, it is necessary to appropriately adjust the composition ratio so that the boundary does not look unnatural. As a result, the composition ratio of the composite map in one image is not binarized between 0% and 100%, but changes continuously.

In step S<b>603 , the image processing unit 107 generates an omnifocal image O(x, y) by synthesizing the captured images according to the synthetic map calculated in step S<b>602 . Assuming that the original captured image is Im(x, y), the image is generated by the following (Equation 7).

In the present embodiment, when attempting to correct a change in luminance value due to a change in focus position, it is conceivable to offset a luminance step due to aperture driving.

7A and 7B are diagrams for explaining the change in brightness when the aperture is driven when the brightness value changes as the focus position is changed. While the brightness increases as the focus position moves, as shown in Fig. 7, we considered a system that maintains the brightness at the start of imaging by narrowing the aperture of the lens when a specific change in brightness is detected. be done. However, even in the system shown in FIG. 7, if the brightness of the captured image is corrected so as to match the brightness at the start of imaging, the image will be corrected in the direction of darkening, and the high brightness portion of the image will be darkened. A problem of coloring or a problem of no saturation occurs.

10A and 10B are diagrams for explaining luminance changes when the diaphragm is driven in the first embodiment. FIG. In the first embodiment, in the calculation of the amount of reduction in exposure in step S303 in FIG. can be imaged so as not to exceed . If the image can be captured as shown in FIG. 8, the image can be corrected in the brighter direction by image processing in step S407 of FIG.

(Second embodiment)
A second embodiment of the present invention will be described below with reference to the drawings. In the second embodiment, unlike the first embodiment, the method of determining exposure when capturing an image is changed depending on whether or not to combine images. Details are described below.

FIG. 9 is a flowchart for explaining generation of a composite image in this embodiment. In the second embodiment, it is assumed that the digital camera 100 is equipped with a plurality of imaging modes, and one of the plurality of imaging modes is the focus stacking mode.

In step S901, the control unit 101 determines whether the imaging mode of the digital camera 100 is set to the focus stacking mode. In the focus stacking mode, the process advances to step S902, and the subsequent processing is as described in the first embodiment. If the focus stacking mode is not set, the flow transitions to step S906.

In step S906, the control unit 101 determines exposure conditions for imaging. Here, similarly to step S302 of the first embodiment, the control unit 101 determines the shutter speed, F number, and ISO sensitivity. The exposure conditions may be set manually by the user, or may be set automatically by the control unit 101 causing the imaging unit 104 to measure the subject.

In step S907, the imaging unit 104 performs imaging according to the exposure conditions determined in step S906. In step S907, even when the imaging unit 104 captures a plurality of images, the exposure conditions used for capturing the plurality of images are left as the exposure conditions determined in step S906.

According to this embodiment, in the case of focus stacking, it is possible to generate a composite image that suppresses coloring and exposure steps by capturing an image with a darker exposure than a predetermined exposure and correcting it in a brighter direction through image processing. In the case of non-focus stacking, imaging can be performed without changing the exposure.

(Other embodiments)
Although focus stacking has been described in the above embodiment, the present invention is not limited to this. Even if the focus position is not changed when taking multiple images, the exposure may change due to uneven light emission when using a strobe or uneven exposure when using a high-speed shutter. FIG. 13 is a diagram for explaining how luminance changes due to uneven light emission or uneven exposure when a plurality of images are captured. When a plurality of images shown in FIG. 13 are combined in some way, brightness unevenness occurs in the combined image, as in the first embodiment. In order to solve such a problem, it is effective to take an image with an exposure lower than a predetermined value as described in the first embodiment.

Although the above embodiment has been described based on implementation in a digital camera, it is not limited to a digital camera. For example, it may be carried out by a mobile device having an image sensor built therein, or by a network camera capable of capturing an image.

In addition, the present invention supplies a program that implements one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device executes the program. can also be realized by a process of reading and operating the It can also be implemented by a circuit (for example, ASIC) that implements one or more functions.

100 Digital Camera 101 Control Unit 102 Driving Unit 103 Optical System 104 Imaging Unit 105 ROM
106 RAMs
107 image processing unit 108 display unit 109 built-in memory 110 operation unit

Claims (26)

determining means for determining a predetermined value of exposure in advance;
imaging means for imaging a plurality of images with different focus positions;
a control means for controlling such that when the image capturing means captures the plurality of images, the images are captured with an exposure lower than the predetermined value;
and correction means for correcting brightness of at least part of the plurality of images based on the predetermined value determined by the determination means. 2. The imaging apparatus according to claim 1, wherein said correcting means corrects the brightness of said partial image so as to match the exposure of at least a partial image of said plurality of images with said predetermined value. 3. The image pickup apparatus according to claim 1, wherein the image pickup means picks up the plurality of images while changing the focus position. 4. The image pickup apparatus according to claim 3, wherein said image pickup means picks up said plurality of images while changing said focus position from a close-up side to an infinity side. 3. The imaging apparatus according to claim 1, wherein said determining means determines said predetermined value based on a photometric amount when capturing a first image among said plurality of images. 3. The imaging apparatus according to claim 1, wherein said determining means determines said predetermined value based on user settings. 3. The control means controls exposure when the image capturing means captures the plurality of images by controlling at least one of a shutter speed, an F number, and an ISO sensitivity. The imaging device according to . an effective F value changes when the imaging means captures the plurality of images,
3. The image pickup apparatus according to claim 1, wherein the control means controls the exposure when the image pickup means takes the plurality of images based on the amount of change in the effective F value. The imaging means captures the plurality of images using a strobe,
3. The image pickup apparatus according to claim 1, wherein the control means controls the exposure when the image pickup means takes the plurality of images based on performance of the strobe. 10. The imaging apparatus according to claim 9, wherein the performance of said strobe includes uneven light emission of said strobe. The imaging means captures the plurality of images using a high-speed shutter,
3. The image pickup apparatus according to claim 1, wherein the control means controls the exposure when the image pickup means takes the plurality of images based on the performance of the high-speed shutter. 12. The image pickup apparatus according to claim 11, wherein the performance of said high-speed shutter includes exposure unevenness due to high-speed shutter. 3. The imaging apparatus according to claim 1, wherein said correction means corrects RAW images, YUV images, or RGB images of said plurality of images. 3. The imaging apparatus according to claim 1, wherein the correcting means performs correction based on an integrated value of RAW green pixels of the plurality of images. 3. The imaging apparatus according to claim 1, wherein said correcting means corrects based on a photometric amount when said imaging means picks up said plurality of images. Synthesizing means for synthesizing the plurality of images to generate a synthetic image,
3. The imaging apparatus according to claim 1, wherein the depth of field of said synthesized image is deeper than the depth of field of said plurality of images. 17. The imaging apparatus according to claim 16, wherein said synthesizing means extracts a focused area of each of said plurality of images to generate said synthesized image. a determining step of predetermining a predetermined value of exposure;
an imaging step of imaging a plurality of images with different focus positions;
a control step of performing control such that when the plurality of images are captured in the imaging step, they are captured with an exposure lower than the predetermined value;
and a correction step of correcting the brightness of at least part of the plurality of images based on the predetermined value determined by the determining means. A program that causes a computer to operate an imaging device,
a determining step of predetermining a predetermined value of exposure;
an imaging step of imaging a plurality of images with different focus positions;
a control step of performing control such that when the plurality of images are captured in the imaging step, they are captured with an exposure lower than the predetermined value;
and a correction step of correcting the brightness of at least part of the plurality of images based on the predetermined value determined by the determining means. determining means for determining a predetermined value of exposure in advance;
imaging means for imaging a plurality of different images;
a control means for controlling exposure when the imaging means captures the plurality of images;
correction means for correcting the brightness of at least part of the plurality of images based on the predetermined value determined by the determination means;
synthesizing means for synthesizing at least part of the plurality of images;
In the first mode for synthesizing, the control means controls such that when the image capturing means captures the plurality of images, the image capturing means captures the images with an exposure lower than the predetermined value, and the correction means performs the correction. do,
In the second mode in which the synthesis is not performed, the control means controls the image pickup means to pick up the plurality of images with the predetermined value. 21. The imaging apparatus according to claim 20, wherein said correction means does not perform said correction in said second mode. 22. The imaging apparatus according to claim 20, wherein the plurality of images have different focus positions. 21. The synthesizing unit generates a synthetic image having a deeper depth of field than the depth of field of at least a part of the plurality of images by performing the synthesizing. 22. The imaging device according to 21. a determining step of predetermining a predetermined value of exposure;
an imaging step of capturing a plurality of different images;
a control step of controlling exposure when capturing the plurality of images in the imaging step;
a correction step of correcting the brightness of at least some of the plurality of images based on the predetermined value determined in the determination step;
a synthesizing step of synthesizing at least part of the plurality of images;
In the first mode of combining, in the control step, when the plurality of images are captured in the imaging step, they are controlled to be captured with an exposure lower than the predetermined value, and in the correction step, the correction is performed. and
In the second mode in which no synthesis is performed, the imaging method is characterized in that, in the control step, when the plurality of images are captured in the imaging step, they are controlled to be captured with the predetermined value. A program that causes a computer to operate an imaging device,
a determining step of predetermining a predetermined value of exposure;
an imaging step of capturing a plurality of different images;
a control step of controlling exposure when capturing the plurality of images in the imaging step;
a correction step of correcting the brightness of at least some of the plurality of images based on the predetermined value determined in the determination step;
performing a synthesizing step of synthesizing at least part of the plurality of images;
In the first mode of combining, in the control step, when the plurality of images are captured in the imaging step, they are controlled to be captured with an exposure lower than the predetermined value, and in the correction step, the correction is performed. and
A computer program characterized in that, in the second mode in which the synthesis is not performed, the controlling step performs control such that when the plurality of images are captured in the imaging step, they are captured with the predetermined value. A computer-readable recording medium recording the program according to claim 19 or 25.

Images