JP2008306442A - Imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform appropriate photographing by computing a diaphragm value using the information of an image imaged in an imaging part and the information of a foreign matter present in the imaging part. <P>SOLUTION: The imaging apparatus is provided with the imaging part 22 for imaging the image by an optical system, and an operation part 33 for computing the diaphragm value using the information relating to the image imaged in the imaging part and the information of the foreign matter present in the imaging part. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an imaging apparatus such as a digital camera.

In a digital camera or the like, there may be a problem that foreign matters such as dust adhering to an image sensor or a low-pass filter are reflected in a captured image. In particular, in a camera in which a movable part such as an interchangeable lens camera, a focal plane shutter, or a quick return mirror is provided in front of the image sensor, dust or the like is likely to adhere to the image sensor or the like.
As a conventional technique, there is known a camera that detects the presence and size of dust on an image sensor and calculates a shutter speed and an aperture value based on the detection result and the output of a photometric means (see Patent Document 1). .
JP 2006-157407 A

  However, in the prior art camera, the aperture value that can be set is excessively restricted, and the range of shooting conditions is narrowed.

  An object of the present invention is to provide an imaging device capable of appropriate photographing.

The present invention solves the above problems by the following means.
In addition, in order to explain the present invention in an easy-to-understand manner, the description has been made in association with the reference numerals of the drawings showing the embodiments. However, the present invention is not limited to this, and the configuration of the embodiments described later is appropriately improved. Alternatively, at least a part of the structure may be replaced with another component. Further, the configuration requirements that are not particularly limited with respect to the arrangement are not limited to the arrangement disclosed in the embodiment, and can be arranged at a position where the function can be achieved.

The invention described in claim 1 uses an image pickup unit (22) for picking up an image by the optical system (11), information on an image picked up by the image pickup unit, and information on a foreign object existing in the image pickup unit. And an imaging unit (1, 1-2, 1-3, 1-4, 1-5, 1-6). Here, the information on the foreign matter existing in the imaging unit may include information on the foreign matter existing on the imaging element, the low-pass filter, and the optical member having transparency disposed on the optical system side from these. Good.
According to a second aspect of the present invention, in the imaging apparatus according to the first aspect, the foreign substance information includes position information of the foreign substance, (1, 1-2, 1-3) , 1-4, 1-5, 1-6).
According to a third aspect of the present invention, in the imaging device according to the first or second aspect, the information on the foreign matter includes size information on the foreign matter. 2,1-3,1-4,1-5,1-6).
According to a fourth aspect of the present invention, in the imaging apparatus according to any one of the first to third aspects, information relating to an image captured by the imaging unit (22) is captured by the imaging unit (22). The image pickup apparatus (1-6) is characterized by the fact that the image information is obtained.
According to a fifth aspect of the present invention, in the imaging apparatus according to any one of the first to third aspects, the observation unit (31) for observing an image corresponding to an image captured by the imaging unit (22). ), And the information on the image captured by the imaging unit is information obtained by the observation unit (1, 1-2, 1-3, 1-4) 1-5).
According to a sixth aspect of the present invention, in the imaging device according to any one of the first to fifth aspects, the calculation unit (33) is obtained from information relating to an image captured by the imaging unit (22). An imaging apparatus (1,1-2,1-3,1-4,1-5,1-6) characterized in that an aperture value is calculated based on at least one of brightness or fineness of an image. .
According to a seventh aspect of the present invention, in the imaging apparatus according to the sixth aspect, the calculation unit (33) is at least one of brightness or fineness within a predetermined range from a position on the image corresponding to the information of the foreign matter. Is an imaging device (1, 1-2, 1-3, 1-4, 1-5, 1-6).
According to an eighth aspect of the present invention, in the imaging apparatus according to any one of the first to seventh aspects, the aperture value calculated by the calculation unit (33) is an aperture value range that can be set by the imaging apparatus. The imaging device (1-2) is characterized by having a sensitivity changing unit (34-2) that changes the sensitivity of the imaging unit (22) when exceeding.
According to a ninth aspect of the present invention, in the imaging apparatus according to any one of the first to eighth aspects, the aperture value calculated by the calculation unit (33) is an aperture value range that can be set by the imaging apparatus. It is an imaging device (1,1-2,1-3,1-4,1-5,1-6) characterized by having a notification part (29) for notifying when exceeding.
According to a tenth aspect of the present invention, in the imaging apparatus according to the ninth aspect, the notifying unit (29) is configured to change the composition or change the attitude of the imaging apparatus so as to be within an aperture value range that can be set by the imaging apparatus. The imaging apparatus (1-3) is characterized in that when the calculation unit can calculate the aperture value, the notification is made.
An eleventh aspect of the present invention is the image pickup apparatus according to the tenth aspect, further comprising a posture detection unit (35) for detecting the posture of the image pickup device, and the notification unit (29) rotates the image pickup device around an optical axis. By doing so, the calculation unit can calculate an aperture value that falls within a range of aperture values that can be set by the imaging device, and the posture detection unit can easily rotate the imaging device around the optical axis. The image pickup apparatus (1-3) is characterized in that, when it is determined from the detection result, the notification is made to that effect.
According to a twelfth aspect of the present invention, in the image pickup apparatus according to any one of the first to eleventh aspects, the removal of foreign matter existing on an optical path through which subject light incident on the image pickup unit (22) passes is removed. An imaging device (1-), wherein the removal unit operates when the aperture value calculated by the calculation unit exceeds an aperture value range that can be set by the imaging device. 4).
According to a thirteenth aspect of the present invention, in the imaging apparatus according to any one of the first to twelfth aspects, the computing unit (33) has a large size among the foreign matters obtained from the size information of the foreign matter. The imaging device (1, 1-2, 1-3, 1-4, 1-5, 1-6) is characterized in that a predetermined number of foreign objects are used in order to calculate an aperture value.
The invention of claim 14 is the imaging apparatus according to any one of claims 1 to 13, further comprising a main subject detection unit (37) for detecting a main subject, wherein the calculation unit (33) An imaging apparatus (1-5), characterized in that a foreign object at a position corresponding to a main subject detected by the main subject detection unit is used for calculating an aperture value.
According to a fifteenth aspect of the present invention, there is provided an image pickup unit (22) for picking up an image by the optical system (11), and an aperture based on at least one of brightness or fineness of the image included in information related to the image picked up by the image pickup unit. And an imaging unit (1, 1-2, 1-3, 1-4, 1-5, 1-6).

  ADVANTAGE OF THE INVENTION According to this invention, the imaging device which can perform suitable imaging | photography can be provided.

(First embodiment)
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram illustrating an overview of the camera of the first embodiment.
The camera 1 has an interchangeable lens 10 and a camera body 20.

The interchangeable lens 10 is an interchangeable unit that has a mount (not shown) that is detachable from the camera body 20 and can be replaced by a photographer as necessary. The interchangeable lens 10 includes a photographing lens 11, a diaphragm 12, a diaphragm driving unit 13, and the like.
The photographic lens 11 is an optical system that forms a subject image on a first imaging unit 22 described later. The photographic lens 11 has different optical specifications such as a focal length and an open aperture value depending on the type of the interchangeable lens.
The diaphragm 12 is an iris diaphragm that limits the amount of subject light that reaches the first imaging unit 22.
The aperture driving unit 13 is a part that drives the aperture 12 according to the aperture value calculated and determined by an aperture value calculating unit 33 described later. The diaphragm drive unit 13 may be configured by a diaphragm lever (not shown) that is engaged with a lever (not shown) provided on the camera body 20 and is spring-driven when the lever is retracted, or an electromagnetic actuator or the like. It may be constituted by.

The camera body 20 includes a main mirror unit 21, a first imaging unit 22, an amplification unit 23, an A / D conversion unit 24, a WB adjustment unit 25, a complement processing unit 26, an external storage device 27, a screen. 28, a notification unit 29, a pentaprism 30, a second imaging unit 31, a foreign object detection unit 32, an aperture value calculation unit 33, a sensitivity change unit 34, and the like.
In the present embodiment, the first imaging unit 22 and the second imaging unit 31 are provided. The imaging unit can substantially perform imaging, but “imaging” is described in the following description. In this case, unless otherwise specified, shooting using the first imaging unit 22 is referred to, and an image obtained from the second imaging unit 31 is referred to as a “preview image”.

  The main mirror unit 21 is a so-called quick return mirror that reflects light that has passed through the photographing lens 11. In the state before photographing, the main mirror unit 21 reflects the light that has passed through the photographing lens 11 as shown in FIG. On the other hand, at the time of shooting, light that has retreated from the shooting optical path and has passed through the shooting lens 11 by opening a shutter (not shown) reaches the first imaging unit 22.

  The first imaging unit 22 includes an imaging element (not shown) and an optical low-pass filter (hereinafter referred to as LPF) disposed on the incident side in the optical axis direction from the imaging element. The first image pickup unit 22 passes through the LPF, reaches the image pickup device, and picks up a subject image formed on the image pickup surface of the image pickup device. Specifically, an analog signal corresponding to the subject image formed on the imaging surface of the image sensor is output to the amplifying unit 23.

  The amplifying unit 23 amplifies the analog signal received from the first imaging unit 22. The amplifying unit 23 changes the degree of amplification of the analog signal according to the instruction from the sensitivity changing unit 34. The amplification unit 23 outputs the amplified analog signal to the A / D conversion unit 24.

The A / D converter 24 is a part that converts the analog signal amplified by the amplifier 23 into a digital signal. The A / D conversion unit 24 outputs the converted digital signal to the WB adjustment unit 25.
The WB adjustment unit 25 is a part that adjusts the white balance of the digital signal converted by the A / D conversion unit 24. The WB adjustment unit 25 outputs the digital signal whose white balance has been adjusted to the complement processing unit 26.

The complement processing unit 26 is a part that complements information between pixels of the digital signal output from the WB adjustment unit 25 by arithmetic processing. The complement processing unit 26 outputs the complemented digital signal to the external storage device 27.
The external storage device 27 is a writing device to which the external storage medium 40 can be attached. The external storage device 27 writes the digital signal obtained from the complement processing unit 26 to the attached external storage medium 40.

The screen 28 is a substantially transparent plate-like member on which subject light reflected by the main mirror unit 21 forms an image. The imaging plane of the screen 28 is provided at a position that is conjugate with the imaging plane of the first imaging unit 22.
The notification unit 29 is an information display device arranged along the outer edge of the screen 28, and is configured by a liquid crystal display element, for example. The notification unit 29 displays the notification content instructed from the aperture value calculation unit described later. Note that the notification unit 29 may have a configuration in which a liquid crystal display element or the like having the same size as the screen 28 is disposed so as to overlap the screen.
The pentaprism 30 is a prism that erects the subject image formed on the screen 28 and the display in the notification unit 29 vertically and horizontally and emits the image to the viewer side.

The second imaging unit 31 includes an imaging element (not shown) and a second optical system (not shown). The second optical system is an optical system that focuses light from the subject image formed on the screen 28 on the imaging surface of the imaging element of the second imaging unit 31. Therefore, the second imaging unit 31 can acquire an image (preview image) having a composition that substantially matches the image that is scheduled to be shot in a state before shooting. The preview image obtained by the second imaging unit 31 is sent to the aperture value calculation unit 33. The preview image obtained by the second imaging unit 31 is sent to the aperture value calculation unit 33 and displayed on a display unit (not shown) for image confirmation provided on the surface of the camera body 20 on the photographer side. You may make it do.
In the present embodiment, the preview image obtained by the second imaging unit 31 is used to determine the shutter speed, aperture value, and shooting sensitivity. In addition to the second imaging unit 31, a photometric unit dedicated to exposure control may be provided.

The foreign object detection unit 32 is a part that detects a foreign object from the image captured by the first imaging unit 22. Specifically, for example, a subject that does not include a subject that becomes a fine image (a subject that becomes an image with a high spatial frequency) such as a white wall or a blue sky is narrowed down as much as possible (with a larger aperture value). Foreign matter is detected using the photographed image. The foreign object detection unit 32 detects a part where the luminance is equal to or less than a predetermined threshold in the image used for foreign object detection as a part having the foreign object. At that time, the foreign object detection unit 32 stores the position and size including the foreign object according to the correspondence with the pixel of the photographed image, and also includes the focal length, the photographing distance, and the aperture value of the interchangeable lens used for the foreign object detection. Remember. In addition, as images used for foreign object detection, a plurality of images with different shooting times and subjects are used, and portions where the luminance is equal to or less than a predetermined threshold exist at the same position in the plurality of images. Sometimes it is possible to improve the accuracy of foreign object detection as being a foreign object.
In the present embodiment, the foreign matter detection unit 32 can perform foreign matter detection using image data that has already been photographed and stored in an external storage medium, or performs photographing for foreign matter detection as necessary. It is also possible to obtain image data directly from the complement processing unit 26 and perform foreign object detection.

The aperture value calculation unit 33 is a part that calculates the aperture value of the aperture 12 when shooting. The aperture value calculation unit 33 calculates the aperture value at the time of shooting using the preview image obtained by the second imaging unit 31 and the information on the position and size of the foreign matter obtained from the foreign matter detection unit 32.
The sensitivity changing unit 34 is a part that gives an instruction to the amplification unit 23 to change the degree of amplification of the analog signal (photographing sensitivity). The sensitivity changing unit 34 changes the photographing sensitivity when instructed by the photographer's input.

Next, the operation of the camera 1 of the first embodiment, particularly the aperture value calculation will be described.
FIG. 2 is a flowchart showing the operation of the camera of the first embodiment.
In step (hereinafter referred to as S) 1, when the photographer presses a release switch (not shown) halfway, the CPU of the camera (not shown) starts a shooting preparation operation (S2). Here, the release switch is a two-stage push-in type switch, and the switch is turned on at the first stage and the second stage, respectively. This is called pushing. In addition, the shooting preparation operation is to turn on the power of the camera that has been in a standby state in order to reduce power consumption, and to make each part of the camera operable, and when the shooting preparation operation is started. The half-press timer for counting the time starts counting. When S2 ends, the process proceeds to S3.
In S <b> 3, a preview image is acquired by the second imaging unit 31. The acquired preview image data is sent to the aperture value calculator 33, and the process proceeds to S4.

In S4, the aperture value is calculated based on the preview image.
FIG. 3 is a flowchart showing in detail the calculation operation of the aperture value calculation unit. The flow of FIG. 3 shows S4 of FIG. 2 in detail.
When the aperture value calculation unit 33 starts the aperture value calculation process (S401), in S402, the luminance information of the subject is obtained from the preview image data, and the aperture value and the aperture value are determined according to a preset standard program diagram. The shutter speed is provisionally determined, and the process proceeds to S403.
In S403, n = 0 is set, and the process proceeds to S404. Here, n determines how many foreign objects detected by the foreign object detection unit 32 are considered in descending order, and determines whether or not the calculation is performed until the determined number is reached. This is a counter variable.
In S404, 1 is added to n, and the process proceeds to S405.

  In S405, the spatial frequency f1 when the nth largest foreign object is photographed with the temporarily determined aperture value is acquired. What spatial frequency image is formed when a foreign object is photographed varies depending not only on the size of the foreign object but also on the focal length of the interchangeable lens, the photographing distance, and the aperture value. Therefore, in this embodiment, an experiment is performed in advance to determine what kind of captured image can be obtained by a combination of the size of the foreign matter, the focal length of the interchangeable lens, the photographing distance, and the aperture value. I remember it. In this step, the aperture value calculation unit 33 detects the spatial frequency f1 when photographing is performed with the tentatively determined aperture value, and the size of the foreign material detected and stored by the foreign material detection unit 32, and the temporarily determined aperture value. Using the focal length of the interchangeable lens 10 and the aperture value, it is obtained from the above-described table.

  In S406, the spatial frequency distribution and brightness around the position corresponding to the nth largest foreign object in the preview image are calculated. The periphery of the position corresponding to the foreign object is, for example, a square region that is a predetermined number of pixels (for example, 10 pixels) away from the center of the foreign object. The reason for limiting to that range is that the processing load can be reduced as compared with the case where the calculation is performed on the entire preview image. The spatial frequency distribution is obtained by performing a two-dimensional Fourier transform.

  In S407, it is determined whether the brightness around the position corresponding to the nth largest foreign object in the preview image is equal to or greater than a predetermined value. Even if the position of the imaging element (photoelectric conversion element) of the first imaging unit 22 and the distance to the imaging unit surface where the foreign matter adheres and the size of the foreign matter are the same, the foreign matter depends on the brightness of the image to be photographed. The effect on the recorded image is different. For example, in landscape photography, it is almost unknown if a foreign object is reflected in the night sky, but if it is reflected in a blue sky, the foreign object becomes conspicuous. Therefore, the subsequent processing is changed depending on the brightness in S407. That is, when the brightness around the position corresponding to the nth largest foreign object in the preview image is equal to or greater than a predetermined value (that is, bright), the foreign object may stand out, and the process proceeds to S408. On the other hand, when the brightness around the position corresponding to the nth largest foreign object in the preview image does not reach the predetermined value (that is, dark), it is determined that the foreign object is not noticeable, and the process proceeds to S410.

In S408, it is determined whether or not an image having a frequency equal to the spatial frequency f1 of the foreign object is included in the preview image includes a frequency equal to or greater than the spatial frequency f1 in the spatial frequency distribution of the image around the position corresponding to the nth largest foreign object. Do.
As in the case of the brightness described above, even if the position of the imaging element (photoelectric conversion element) of the first imaging unit 22 and the distance to the imaging unit surface on which the foreign matter adheres and the size of the foreign matter are the same, take a picture. The influence of foreign matter on the recorded image varies depending on the fineness (spatial frequency) condition of the image. For example, a foreign object is less conspicuous in an image in which the spatial frequency of a subject image at a position where the foreign object overlaps contains a lot of frequency components that are comparable or relatively higher than the size of the foreign object.

FIG. 4 is a diagram for explaining how to determine whether or not a foreign object is inconspicuous from the relationship between the foreign object and the preview image. FIG. 4A schematically shows the distribution of foreign matter detected by the foreign matter detection unit 32. Here, it is assumed that the foreign objects P1 and P2 are detected by the foreign object detection unit 32 above and below the left and right center of the screen, respectively. FIG. 4B shows an example of a preview image. Here, it is assumed that the position corresponding to the foreign matter P1 is a blue sky, and the position corresponding to the foreign matter P2 is a mountain.
FIG. 4C shows a spatial frequency distribution obtained by performing two-dimensional Fourier transform on an image around the position corresponding to the foreign substance P1 (here, the blue sky) in the preview image. Since FIG. 4C is for the blue sky, there are many low-frequency image components and few high-frequency image components. FIG. 4C also shows the spatial frequency f1 of the foreign matter P1. In the example of FIG. 4C, the image component of the frequency f1 is small in the preview image and does not reach the threshold value g. When photographing is performed in such a case, it can be said that foreign matter is conspicuous.

On the other hand, FIG. 4D shows a spatial frequency distribution obtained by performing a two-dimensional Fourier transform on an image around a position corresponding to the foreign substance P2 (here, a mountain) in the preview image. Since FIG. 4D is intended for a mountain, there are many image components of various frequencies including high frequencies. FIG. 4D also shows the spatial frequency f1 of the foreign matter P2. In the example of FIG. 4D, many image components of the frequency f1 are present in the preview image and exceed the threshold value g. When photographing is performed in such a case, it can be said that the foreign matter is not noticeable.
In the above description, whether or not a foreign object is noticeable is determined based on the amount of a frequency component equal to the frequency f1 existing in the preview image. The determination method is not limited to this, and as shown in FIGS. 4C and 4D, a frequency f2 larger than the frequency f1 by a predetermined frequency, that is, a frequency f2 corresponding to a finer image is set. Whether or not a foreign object is noticeable may be determined based on the total amount (integrated value) of components having frequency components up to f2, or may be determined based on the total amount of components greater than or equal to f1 without setting f2. .
Note that the threshold value g is used to determine whether or not a foreign object is conspicuous, but the determination of whether or not a foreign object is conspicuous depends largely on human perception. Therefore, the setting of the threshold value g may be determined in advance from data obtained by a preliminary experiment or the like, for example. The threshold value g may be different depending on the spatial frequency band. In such a case, the threshold value g may be stored in a table format.

  Returning to FIG. 3, as described above, the subsequent processing is changed in S408 according to the fineness (spatial frequency) of the image of the preview image. That is, when a preview image includes an image having a frequency equal to or greater than the spatial frequency f1 of the foreign object around the position corresponding to the nth largest foreign object (that is, a size similar to that of the foreign object). When a large number of images are overlapped), it is determined that the foreign matter is not noticeable, and the process proceeds to S410. On the other hand, when an image having a frequency equal to the spatial frequency f1 of the foreign object is not included in the periphery of the position corresponding to the nth largest foreign object in the preview image, the image has a size similar to that of the foreign object. Since the foreign matter may be conspicuous, the process proceeds to S409.

  In S409, the aperture value is determined with reference to the table so that the image of the frequency f1 is equal to or greater than the threshold value g, and the process proceeds to S411. The fact that the process has proceeded to this step can be determined that foreign objects are conspicuous with the aperture value provisionally determined in S402. When the aperture value is small, that is, the aperture diameter is large and a large amount of light can be guided to the first imaging unit 22, the depth of field becomes shallow, and the influence of foreign matter on the recorded image is reduced. Therefore, the spatial frequency f1 of the foreign matter can be changed to the low frequency side by decreasing the aperture value. For example, in the case of FIG. 4C described above, if the spatial frequency f1 of the foreign substance changes to the low frequency side, the image component of the changed frequency f1 included in the preview image exists beyond the threshold value g. , Foreign objects become inconspicuous.

  In S410, the aperture value provisionally determined in S402 remains unchanged, and the process proceeds to S411. Unlike the case where the process proceeds to S409, the fact that the process has proceeded to this step can be determined that the foreign matter does not stand out even if the aperture value temporarily determined in S402 remains.

  In S411, it is determined whether or not the counter n has reached a predetermined value (for example, 10). When the counter n has reached the predetermined value, the processing for the set number of foreign matters has been completed, so the process proceeds to S412 and the aperture value calculation processing is ended. On the other hand, when the counter n has not reached the predetermined value, the process proceeds to S404, the counter is advanced, and the above processing is repeated. In the case where the steps after S404 are performed after n = 2 and the aperture value has already been changed, the aperture value after the change is replaced with the aperture value temporarily determined in S402, and Perform processing.

Returning to FIG. 2, in S5, the shutter speed is determined based on the aperture value calculated by the aperture value calculation process in S4, and the process proceeds to S6. Obtaining the aperture value in S4 is equivalent to changing the program diagram so as to change the upper limit value of the aperture value on the program diagram if expressed in another way.
FIG. 5 is a program diagram that changes in the first embodiment.
When there is no influence of foreign matter, the upper limit value of the aperture value is the maximum aperture value that can be set by the interchangeable lens. If there is an influence of foreign matter but the influence is relatively small, the upper limit value of the aperture value is lowered. When the influence of foreign matter is large, the upper limit value of the aperture value is further lowered to suppress the influence of foreign matter.

  Returning to FIG. 2, in S6, it is determined whether or not the aperture value determined in S5 can be set. Whether or not setting is possible is a value that exceeds the minimum aperture value (open aperture value) of the interchangeable lens 10 being used, or a high-speed shutter that is necessary for obtaining a proper exposure because the subject brightness is too high. May not be set by the camera 1. If it can be set, the process proceeds to S8, and if it cannot be set, the process proceeds to S7.

In S7, the aperture value that makes the foreign object inconspicuous cannot be set, and the notification unit 29 notifies that the foreign object may be noticeable in the captured image, and then the process proceeds to S8. In this case, the aperture value and the shutter speed are newly determined as a program diagram in which the aperture value is as small as possible.
Further, when the exposure mode setting of the camera 1 is not the above-described program mode but the aperture priority AE mode, the shutter speed is uniquely determined by the photographer determining the aperture value. In this case, when the aperture value determined by the photographer is larger than the aperture value that is assumed to be less affected by foreign matter, the notification unit 29 notifies the photographer accordingly.
Similarly, in the shutter speed priority AE mode, the aperture value is uniquely determined by the photographer determining the shutter speed. At this time, when the aperture value is larger than the aperture value that is assumed to be less affected by the foreign matter, the notification unit 29 notifies the photographer accordingly.

  In S8, it is determined whether or not the release switch is fully pressed. If the release switch is fully pressed, the process proceeds to S10. If the release switch is not fully pressed, the process proceeds to S9.

  In S9, it is determined from the count of the half-press timer whether or not a predetermined time has elapsed since the release switch was half-pressed. If a predetermined time or more has elapsed since the release switch was pressed halfway, the process proceeds to S13 and the operation is terminated. If the predetermined time has not elapsed since the release switch was pressed halfway, the process returns to S3.

In S10, the diaphragm 12 is narrowed down, the main mirror unit 21 is retracted from the optical path, and the process proceeds to S11.
In S11, a shutter (not shown) is opened, subject light is exposed to the first imaging unit 22, and after a predetermined time has elapsed, the shutter is closed and shooting is performed.
In S12, the main mirror unit 21 is returned to the optical path, the aperture 12 is opened, and then the process proceeds to S13 and the operation is finished.

According to the present embodiment, the aperture value is changed only when a foreign object is conspicuous with respect to the preview image obtained by the second imaging unit 31. Therefore, the foreign object can be removed without excessively restricting the aperture value that can be set. Can be inconspicuous. Therefore, photographing with a high degree of freedom can be performed.
Further, when it is impossible to set the aperture value to make the foreign object inconspicuous and there is a possibility that the foreign object may be noticeable in the image after shooting, the notification is performed by the notification unit 29, so that the image is taken without knowing that the foreign object is noticeable. Can be prevented.

(Second Embodiment)
FIG. 6 is a diagram for explaining the outline of the camera of the second embodiment.
Note that, in the following description of each embodiment, parts having the same functions as those of the above-described first embodiment are denoted by the same reference numerals, and redundant description will be appropriately omitted.
The camera 1-2 of the second embodiment differs from the camera 1 of the first embodiment in the operation of the sensitivity changing unit 34-2.
The sensitivity changing unit 34-2 is a part that gives an instruction to the amplification unit 23 to change the degree of amplification of the analog signal (imaging sensitivity: ISO sensitivity). The sensitivity changing unit 34 changes the shooting sensitivity when instructed by the photographer's input or when received from the aperture value calculating unit 33.

The case where the sensitivity changing unit 34-2 receives an instruction from the aperture value calculating unit 33 and changes the photographing sensitivity is a case where notification is required in S7 in FIG. 2 of the first embodiment. Specifically, when the subject brightness is high and an aperture value that is assumed to have little influence of foreign matter to obtain a proper exposure cannot be selected, the photographing sensitivity is automatically reduced.
Similarly, in the shutter speed priority AE mode, when the aperture value determined by the photographer determining the shutter speed is larger than the aperture value that is assumed to be less affected by foreign matter, the imaging sensitivity is automatically reduced.

  According to the present embodiment, the sensitivity changing unit 34-2 receives an instruction from the aperture value calculating unit 33 and changes the shooting sensitivity. Therefore, it is possible to further increase the possibility of performing shooting that makes the foreign matter inconspicuous.

(Third embodiment)
FIG. 7 is a diagram for explaining the outline of the camera of the third embodiment.
The camera 1-3 according to the third embodiment is different from the camera 1 according to the first embodiment in that the posture detection unit 35 is provided.
The posture detection unit 35 is a part that detects in what direction the camera is held with respect to the direction of gravity. The posture detection unit 35 includes, for example, a device that has small spheres that move according to gravity when the posture of the camera is changed, and that detects the posture based on the position of the small spheres. The detection result of the posture detection unit 35 is transmitted to the aperture value calculation unit 33.

In most cases, the recording area of the image pickup device has an axial target shape (for example, a rectangle or a square) with respect to the optical axis. In particular, in a camera having a general rectangular recording area, in photographing at a so-called vertical position (a state where the camera is held as a photographing area long in the vertical direction), by rotating 180 degrees around the optical axis, 2 In many cases, it is configured to be able to shoot even if any of the two short sides is held on the upper side, and as a result of shooting, shooting can be performed with a similar composition in any way.
FIG. 8 is a diagram illustrating an example of a composition when the third embodiment works effectively. FIG. 8A shows a preview image before the composition change and the detection result of the foreign object detection unit 32. FIG. 8B shows a state when the composition is changed to a composition rotated 180 degrees around the optical axis.

In the state of FIG. 8A, a large foreign matter P3 is attached to one side of the recording area of the first imaging unit 22, and the position thereof overlaps the blue sky portion of the preview image. In this state, when the aperture value is calculated by the aperture value calculator 33 as in the first embodiment, it is determined that the aperture value cannot be set in S6 of the flow of FIG. In this case, in the present embodiment, as shown in FIG. 8B, if the position of the foreign object is moved with respect to the preview image by reversing the holding method, whether the foreign object becomes inconspicuous, and Whether or not an aperture value that can be inconspicuous can be set is determined by calculating, for example, in the same manner as the method shown in FIG. Then, as shown in FIG. 8 (b), if the aperture is reversed or the aperture value can be set so that the foreign object is not noticeable, the fact that the notice value is displayed on the notification unit 29 is displayed. That is, a display that recommends changing to a composition rotated 180 degrees around the optical axis is performed.
In general, it is often difficult to hold the camera in the opposite direction when the camera is held in a horizontal position (a camera position where the shooting screen is elongated in the horizontal direction).
Therefore, in the present embodiment, when the posture detection unit 35 is provided and the manner of holding the camera detected by the posture detection unit 35 is in the horizontal position, the display using the notification unit 29 is not performed, and the case of the vertical position is used. Only the display is recommended to change to a composition rotated 180 degrees around the optical axis.

  In the present embodiment, when the foreign object can be made inconspicuous by the way of holding the camera 1 with respect to the size and position of the foreign object, the brightness of the image to be photographed, the spatial frequency, etc., this is notified to the photographer. Because it communicates, the possibility of making foreign objects inconspicuous can be further increased.

(Fourth embodiment)
FIG. 9 is a diagram for explaining the outline of the camera of the fourth embodiment.
The camera 1-4 according to the fourth embodiment is different from the camera 1 according to the first embodiment in that a foreign matter removing unit 36 is provided.
The foreign matter removing unit 36 is disposed between the main mirror unit 21 and the first imaging unit 22, and the first imaging unit 22 is placed on the main body so as to prevent foreign matter from adhering to the first imaging unit 22. It is isolated and sealed from the mirror unit 21 side. Further, the foreign matter removing unit 36 includes a light transmitting unit (not shown) formed of a member having translucency and a vibration unit (not shown) that applies vibration to the light transmitting unit. The excitation unit is made of, for example, a motor having a piezoelectric element or an eccentric piece, and can generate vibrations when energized, and can perform an operation of removing foreign substances attached to the surface of the light transmitting unit.

  In this embodiment, when the notification of S7 shown in the flow of FIG. 2 is necessary, that is, when it is impossible to set the aperture value calculated by the aperture value calculation unit 33, the foreign substance removal unit 36 operates. . Therefore, the foreign substance removing operation by the foreign substance removing unit 36 can be performed at a timing at which the effect can be exhibited. Further, the foreign substance removing unit 36 may be operated only when the aperture value calculated by the aperture value calculating unit 33 cannot be set. By doing so, it is possible to prevent the foreign matter removing unit 36 from operating when it is not necessary to operate the foreign matter removing unit 36, and it is possible to prevent waste of power.

(Fifth embodiment)
FIG. 10 is a diagram for explaining the outline of the camera of the fifth embodiment.
The camera 1-5 of the fifth embodiment is different from the camera 1 of the first embodiment in that it includes a face detection unit 37 and an image processing unit 38.
The face detection unit 37 obtains information of the preview image obtained by the second imaging unit 31, and includes various information such as the contour shape of the face, the distance between each part such as eyes, nose, mouth, ears, and skin color information. Information is obtained, and these are calculated and analyzed to recognize a human face and detect the position of the face. The face detection unit 37 transmits information regarding the position of the face to the aperture value calculation unit 33.
The image processing unit 38 is a part that removes foreign matter by performing image processing on image data after photographing.

In the present embodiment, the aperture value calculation unit 33 performs a calculation for changing the aperture value only when a foreign object is present at a position corresponding to the face position detected by the face detection unit 37.
In addition, when the aperture value is changed for the foreign object at the position corresponding to the face position, the aperture value calculation unit 33 notifies the image processing unit 38 of information regarding the foreign object.
Based on the information obtained from the aperture value calculation unit 33, the image processing unit 38 performs image processing on the foreign matter that is still noticeable even if the aperture value is changed, and removes the foreign matter.
In this embodiment, since the calculation for changing the aperture value is performed only when a foreign object exists at a position corresponding to the position of the face detected by the face detection unit 37, the usable aperture value is limited. Can be less frequent. Therefore, shooting with a higher degree of freedom can be performed. In addition, arithmetic processing can be reduced, processing speed can be improved, and power consumption can be reduced.

Furthermore, by combining the image processing by the image processing unit 38, the following effects can be obtained in addition to the above effects. If foreign matter is removed by image processing, details in detail will be lost. Therefore, it is not desirable to perform image processing on the face that is the main subject.
Therefore, in the present embodiment, for the face that is the main subject, by changing the aperture value, the foreign object is optically made inconspicuous, and the other foreign object remaining in the less important part is imaged. Processing is to be performed. This effect is not an effect obtained by combining the effect of simply changing the aperture value and the effect of removing foreign matter by image processing, but is an effect obtained only by using these in combination in the above-described form.

(Sixth embodiment)
FIG. 11 is a diagram for explaining the outline of the camera of the sixth embodiment.
A camera 1-6 according to the sixth embodiment is different from the camera 1 according to the first embodiment in that the second imaging unit 31 is not provided. Then, the aperture value calculation unit 33 changes the aperture value using the preview image obtained from the first imaging unit 22.
FIG. 12 is a flowchart showing the operation of the camera of the sixth embodiment.
In the sixth embodiment, the aperture value calculation unit 33 performs a calculation for changing the aperture value after the release switch is fully pressed. Therefore, the operation shown in FIG. 12 will be described as an operation after the release switch is fully pressed.

When the photographer fully presses the release switch in S201, the camera CPU retracts the main mirror unit 21 from the optical path (S202). When S202 ends, the process proceeds to S203.
In S <b> 203, a preview image is acquired by the first imaging unit 22 by operating a shutter (not shown). The acquired preview image data is sent to the aperture value calculator 33, and the process proceeds to S204.
In S204, the aperture value is calculated based on the preview image. Specifically, the same calculation as in the first embodiment is performed, except that the preview image is acquired by the first imaging unit 22.
In S205, the shutter speed is determined based on the aperture value calculated by the aperture value calculation process in S204, and the process proceeds to S206.

  In S206, it is determined whether or not the aperture value determined in S205 can be set. Whether or not setting is possible is a value that exceeds the minimum aperture value (open aperture value) of the interchangeable lens 10 being used, or a high-speed shutter that is necessary for obtaining a proper exposure because the subject brightness is too high. May not be set by the camera 1. If it can be set, the process proceeds to S208. If it cannot be set, the process proceeds to S207.

In S207, the notification unit 29 notifies that the aperture value that makes the foreign object inconspicuous cannot be set, and there is a possibility that the foreign object may be conspicuous in the captured image, and then proceeds to S210. In this case, the aperture value and the shutter speed are newly determined as a program diagram in which the aperture value is as small as possible.
In S210, the diaphragm 12 is narrowed down and the process proceeds to S211.
In S211, the shutter is opened, the first imaging unit 22 is exposed to subject light, and after a predetermined time has elapsed, the shutter is closed and shooting is performed.
In S212, the main mirror unit 21 is returned to the optical path, the aperture 12 is opened, and then the process proceeds to S213 and the operation is terminated.
According to the present embodiment, the aperture value can be changed using the preview image even with only the first imaging unit 22. Therefore, a simpler configuration can be obtained.

As described above, this embodiment has the following effects.
(1) Since the aperture value calculation unit 33 calculates the aperture value using the information about the image to be captured and the detection result of the foreign object detection unit 32, the aperture value is not easily affected by the foreign object and can be set. Shooting without excessive restrictions.
(2) Since the aperture value calculation unit 33 calculates the aperture value using the position information of the foreign matter and the size information of the foreign matter, more accurate aperture value calculation can be performed.
(3) Since the aperture value calculation unit 33 performs calculation using the preview image acquired by imaging with the first imaging unit 22, it is not necessary to provide the second imaging unit, and the configuration can be simplified.
(4) Since the aperture value calculation unit 33 performs the calculation using the preview image obtained by imaging by the second imaging unit 31, the aperture value can be calculated in advance before shooting and the convenience can be improved. .
(5) Since the aperture value calculation unit 33 performs calculation using the brightness and fineness of the image obtained from the preview image, the aperture value can be changed only when a foreign object is noticeable.
(6) Since the aperture value calculation unit 33 performs calculation using the brightness and fineness within a predetermined range from the position on the image corresponding to the foreign object, the calculation load can be reduced.
(7) Since the aperture value calculated by the aperture value calculator 33 includes the sensitivity changing unit 34-2 that changes the sensitivity of the imaging unit when the aperture value range exceeds a settable aperture value range, imaging conditions that can reduce the influence of foreign matter Can be further expanded.
(8) Since the aperture value calculated by the aperture value calculation unit 33 includes the notification unit 29 that notifies when the aperture value exceeds a settable aperture value range, appropriate information can be given to the photographer.
(9) When the aperture value calculation unit 33 can calculate the aperture value within the settable aperture value range by changing the composition or changing the posture of the camera 1, the notification unit 29 notifies the fact to that effect. As a result, the influence of foreign matter can be reduced without changing the aperture value.
(10) When it is determined from the detection result of the posture detection unit 35 that the posture detection unit 35 is provided and the operation of rotating the camera 1 around the optical axis is easy, the notification unit 29 makes a notification to that effect. Therefore, it is possible to provide appropriate guidance without recommending the photographer to an operation that is impossible in practice.
(11) The foreign matter removing unit 36 is operated, and the foreign matter removing unit 36 operates when the aperture value calculated by the aperture value calculating unit 33 exceeds the aperture value range that can be set by the camera 1. Can be prevented.
(12) The aperture value calculation unit 33 is used for the calculation of the aperture value for a predetermined number of foreign objects in order from the largest to the smallest, so that the calculation is not performed even for minute foreign objects that are hardly noticeable. , The processing load can be reduced.
(13) It has a face detection unit 37 for detecting a face, and the aperture value calculation unit 33 is used for calculation of the aperture value for the foreign substance at the face position detected by the face detection unit 37. Foreign matter at the corresponding position can be made inconspicuous.

(Deformation)
As described above, various modifications and changes are possible without being limited to the embodiments described above, and these are also within the scope of the present invention.
(1) In each embodiment, an example in which an aperture is calculated using information in a preview image at a position corresponding to a foreign object has been described. However, information about an image to be captured (such as the fineness and roughness of a subject included in the image) ) And foreign object information, the aperture is not limited to that shown in the above-described embodiment. For example, the aperture may be calculated using the roughness of the entire image to be captured and the size of the foreign object. . The calculation of the aperture value includes information that associates information about an image captured by the imaging unit with information on a foreign object existing in the imaging unit based on a preset correspondence table.

(2) In each embodiment, the example used when calculating the aperture value in the descending order of the size of the foreign matter in the entire imaging range is shown. However, the present invention is not limited to this. It may be divided into regions, and a predetermined number of processes may be performed in order from the larger foreign matter within each divided region. In this way, processing can be performed more efficiently.

(3) In each embodiment, although the notification part 29 showed the example which displays in a finder, not only this but a display apparatus etc. which were provided in the back surface of the camera main body 20 were displayed. Alternatively, a voice notification may be performed.

(4) In the fifth embodiment, an example is shown in which a face is detected as a main subject. However, the present invention is not limited to this. For example, another subject that can specify the color, shape, etc. of the subject, for example, an animal It may be a face, a building, a car, a train, an airplane, a ship, a flower or the like.

It is a figure explaining the outline | summary of the camera of 1st Embodiment. It is a flowchart which shows operation | movement of the camera of 1st Embodiment. It is a flowchart which shows the calculation operation | movement of an aperture value calculating part in detail. It is a figure explaining how to determine whether a foreign material is not conspicuous from the relationship between a foreign material and a preview image. It is a program diagram which changes in 1st Embodiment. It is a figure explaining the outline | summary of the camera of 2nd Embodiment. It is a figure explaining the outline | summary of the camera of 3rd Embodiment. It is a figure which shows an example of a composition in case 3rd Embodiment acts effectively. It is a figure explaining the outline | summary of the camera of 4th Embodiment. It is a figure explaining the outline | summary of the camera of 5th Embodiment. It is a figure explaining the outline | summary of the camera of 6th Embodiment. It is a flowchart which shows operation | movement of the camera of 6th Embodiment.

Explanation of symbols

1: Camera, 10: Interchangeable lens, 20: Camera body

DESCRIPTION OF SYMBOLS 11: Shooting lens, 12: Aperture, 13: Aperture drive part 21: Main mirror part, 22: 1st imaging part, 23: Amplification part, 24: A / D conversion part, 25: WB adjustment part, 26: Complementary process 27: External storage device, 28: Screen, 29: Notification unit, 30: Penta prism, 31: Second imaging unit, 32: Foreign object detection unit, 33: Aperture value calculation unit, 34: Sensitivity change unit

Claims (15)

An imaging unit for imaging an image by an optical system;
A calculation unit that calculates an aperture value using information related to an image picked up by the image pickup unit and information on a foreign object existing in the image pickup unit;
An imaging apparatus comprising: The imaging apparatus according to claim 1,
The foreign object information includes positional information of the foreign object,
An imaging apparatus characterized by the above. In the imaging device according to claim 1 or 2,
The foreign matter information includes size information of the foreign matter,
An imaging apparatus characterized by the above. In the imaging device according to any one of claims 1 to 3,
The information regarding the image captured by the imaging unit is information of the image captured by the imaging unit;
An imaging apparatus characterized by the above. In the imaging device according to any one of claims 1 to 3,
An observation unit for observing an image corresponding to an image captured by the imaging unit;
The information about the image captured by the imaging unit is information obtained by the observation unit;
An imaging apparatus characterized by the above. In the imaging device according to any one of claims 1 to 5,
The arithmetic unit calculates an aperture value based on at least one of brightness or fineness of an image obtained from information about an image captured by the imaging unit;
An imaging apparatus characterized by the above. The imaging device according to claim 6,
The calculation unit calculates an aperture value based on at least one of brightness or fineness within a predetermined range from a position on the image corresponding to the information of the foreign matter;
An imaging apparatus characterized by the above. In the imaging device according to any one of claims 1 to 7,
Having a sensitivity changing unit that changes the sensitivity of the imaging unit when the aperture value calculated by the calculating unit exceeds an aperture value range that can be set by the imaging device;
An imaging apparatus characterized by the above. In the imaging device according to any one of claims 1 to 8,
Having a notification unit for making a notification when the aperture value calculated by the calculation unit exceeds an aperture value range that can be set by the imaging device;
An imaging apparatus characterized by the above. The imaging device according to claim 9,
The notification unit notifies when the calculation unit can calculate the aperture value within the aperture value range that can be set by the imaging device by changing the composition or changing the attitude of the imaging device. thing,
An imaging apparatus characterized by the above. The imaging device according to claim 10.
Having an attitude detection unit for detecting the attitude of the imaging device;
The notification unit can rotate the imaging device around the optical axis so that the calculation unit can calculate an aperture value within a range of aperture values that can be set by the imaging device, and the imaging device can be operated around the optical axis. When it is determined from the detection result of the posture detection unit that the operation of rotating at is easy, a notification to that effect is made,
An imaging apparatus characterized by the above. The imaging apparatus according to any one of claims 1 to 11,
A removal unit that removes foreign matter existing on an optical path through which subject light incident on the imaging unit passes;
The removal unit operates when the aperture value calculated by the calculation unit exceeds an aperture value range that can be set by the imaging device;
An imaging apparatus characterized by the above. The imaging apparatus according to any one of claims 1 to 12,
The calculation unit is used to calculate an aperture value for a predetermined number of foreign objects in order of size from among the foreign objects obtained from the foreign object size information;
An imaging apparatus characterized by the above. The imaging apparatus according to any one of claims 1 to 13,
A main subject detection unit for detecting the main subject;
The calculation unit is used to calculate an aperture value for a foreign object at a position corresponding to the main subject detected by the main subject detection unit;
An imaging apparatus characterized by the above. An imaging unit for imaging an image by an optical system;
A calculation unit that calculates an aperture value based on at least one of brightness or fineness of an image included in information about an image captured by the imaging unit;
An imaging apparatus comprising: