JP2007025098A - Camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To appropriately keep the brightness of the image of a subject when imaging a subject located at a long distance from an imaging device or a subject located at a short distance from the imaging device by using an illuminator. <P>SOLUTION: An imaging part 28 images the subject through a diaphragm part 32 and a lens 30 provided on an optical path from the subject to a camera main body 102. A distance information acquiring part 48 acquires distance information showing a distance to the subject from a lens 104. A first information arithmetic part 48 obtains the diaphragm value of the diaphragm part 32 by using the distance information. A diaphragm decision part 48 decides a diaphragm value obtained by the first information arithmetic part 48 as the diaphragm value of the diaphragm part 32 when imaging the subject by using the illuminator 106 irradiating the subject with irradiating light. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a camera that automatically sets a combination of an aperture value of an aperture and an exposure time.

This type of camera includes, for example, an image sensor such as a CCD (Charge Coupled Device) that images a subject through a photographic lens attached to the camera body, a shutter provided at a position that blocks an optical path from the subject to the image sensor, and a subject. A diaphragm unit provided on the optical path to the image sensor, a photometric unit that measures incident light from the subject to the camera body, and the like. When imaging using an illuminating device that irradiates the subject with illumination light, the combination of aperture value and exposure time is automatically set according to the program diagram that uses the imaging sensitivity of the image sensor and the photometric result measured by the photometric unit. (For example, Patent Document 1). For example, when a subject is imaged using an illumination device, the upper limit value and the lower limit value of the aperture value are set by adjusting the imaging sensitivity and changing the program diagram.
JP 2003-241248 A

  However, in the above-described camera, when the subject is imaged using the illumination device, the upper limit value and the lower limit value of the aperture value are set using only the imaging sensitivity and the photometric result regardless of the distance to the subject. Therefore, when imaging a subject located at a distance from the image sensor using a wide-angle lens or the like, reflected light from the subject due to flash emission of the illumination device is set by setting the upper limit of the aperture value to a large value. The exposure amount of the image sensor is insufficient (underexposure). Also, when imaging a subject located at a short distance from the image sensor using a macro lens or the like, the lower limit of the aperture value is set to a small value, so that the exposure amount of the image sensor is over and the image of the subject is Sometimes it becomes too bright (out-of-white). For this reason, there has been a problem that the brightness of the image of the subject cannot be maintained appropriately.

  An object of the present invention is a camera that automatically sets a combination of an aperture value of an aperture and an exposure time, and uses an illuminating device to shoot a subject located at a long distance from an image sensor or located at a short distance from an image sensor An object of the present invention is to keep the brightness of an image of a subject appropriately when capturing a subject to be photographed.

  In the camera according to the first aspect, the imaging unit images the subject through a diaphragm unit and a lens provided on an optical path from the subject to the camera body. The distance information acquisition unit acquires distance information indicating the distance to the subject from the lens. The first information calculation unit obtains the aperture value of the aperture unit using the distance information. The aperture determination unit determines the aperture value of the aperture unit to be the aperture value obtained by the first information calculation unit when the subject is imaged using the illumination device that irradiates the subject with irradiation light.

According to another aspect of the camera of the present invention, the first information calculation unit obtains a ratio between imaging information and distance information, which is information related to imaging conditions of the imaging unit, as an aperture value of the aperture unit.
According to another aspect of the camera of the present invention, the rate-of-change calculating unit compares the pre-imaging distance information and the pre-imaging distance information acquired by the distance information acquisition unit before and during the imaging, respectively. Calculate the rate of change. When the change rate calculated by the change rate calculation unit exceeds a predetermined value, the distance information setting unit weights the pre-imaging distance information more than the imaging time distance information, and calculates the average value of the pre-imaging distance information and the imaging distance information. When a value close to the pre-imaging distance information is set as the distance information, and the rate of change is less than or equal to a predetermined value, the pre-imaging distance information is weighted smaller than the imaging distance information, and the average value of the pre-imaging distance information and the imaging distance information A value closer to the imaging distance information is set as the distance information. The first information calculation unit includes a second information calculation unit that obtains an aperture value using the distance information set by the distance information setting unit.

  According to another aspect of the camera of the present invention, the imaging unit images the subject through a diaphragm unit and a lens provided on the optical path from the subject to the camera body. The distance information acquisition unit acquires distance information indicating the distance to the subject from the lens. The light emission information acquisition unit acquires preliminary light emission information indicating the preliminary light emission amount of the illumination device from the illumination device that irradiates the subject with irradiation light. The first information calculation unit obtains the aperture value of the aperture unit using the preliminary light emission information and the distance information. The aperture determination unit determines the aperture value of the aperture unit to be the aperture value obtained by the first information calculation unit when the subject is imaged using the illumination device.

According to another aspect of the camera of the present invention, the first information calculation unit obtains a ratio between the product of the imaging information and the preliminary light emission information, which is information related to the imaging condition of the imaging unit, and the distance information as the aperture value of the aperture unit.
In the camera according to claim 6, the change rate calculation unit compares the pre-imaging distance information and the imaging time distance information acquired by the distance information acquisition unit before and at the time of imaging, respectively, and calculates the imaging distance information with respect to the pre-imaging distance information. Calculate the rate of change. When the change rate calculated by the change rate calculation unit exceeds a predetermined value, the distance information setting unit weights the pre-imaging distance information more than the imaging time distance information, and calculates the average value of the pre-imaging distance information and the imaging distance information. When a value close to the pre-imaging distance information is set as the distance information, and the rate of change is less than or equal to a predetermined value, the pre-imaging distance information is weighted smaller than the pre-imaging distance information, and the average value of the pre-imaging distance information and the distance information during imaging A value closer to the imaging distance information is set as the distance information. The first information calculation unit includes a second information calculation unit that obtains an aperture value using the preliminary light emission information and the distance information set by the distance information setting unit.

  According to another aspect of the camera, the imaging unit images the subject through a diaphragm unit and a lens provided on the optical path from the subject to the camera body. The distance information acquisition unit acquires distance information indicating the distance to the subject from the lens. The bounce information acquisition unit acquires bounce information indicating a bounce state in which the subject is indirectly irradiated with the irradiation light from the illumination device that irradiates the subject with the irradiation light. The first information calculation unit obtains the aperture value of the aperture unit using the bounce information and the distance information. The aperture determination unit determines the aperture value of the aperture unit to be the aperture value obtained by the first information calculation unit when the subject is imaged using the illumination device that irradiates the subject with irradiation light.

According to another aspect of the camera of the present invention, the first information calculation unit obtains the ratio of the product of the imaging information and bounce information, which is information related to the imaging conditions of the imaging unit, and the distance information as the aperture value of the aperture unit.
In the camera according to claim 9, the change rate calculation unit compares the pre-imaging distance information and the pre-imaging distance information acquired by the distance information acquisition unit before and during the imaging, respectively, and compares the pre-imaging distance information with the pre-imaging distance information. Calculate the rate of change. When the change rate calculated by the change rate calculation unit exceeds a predetermined value, the distance information setting unit weights the pre-imaging distance information more than the imaging time distance information, and calculates the average value of the pre-imaging distance information and the imaging distance information. When a value close to the pre-imaging distance information is set as the distance information, and the rate of change is less than or equal to a predetermined value, the pre-imaging distance information is weighted smaller than the imaging distance information, and the average value of the pre-imaging distance information and the imaging distance information A value closer to the imaging distance information is set as the distance information. The first information calculation unit includes a second information calculation unit that obtains an aperture value using the bounce information and the distance information set by the distance information setting unit.

  According to another aspect of the camera of the present invention, the upper limit value storage unit stores an externally input value as an aperture upper limit value that is an upper limit value of the aperture value. The aperture determining unit determines the aperture upper limit value as the aperture value of the aperture unit during imaging when the aperture value determined by the first information calculating unit is equal to or less than the aperture upper limit value, and the aperture determined by the first information calculating unit When the value exceeds the aperture upper limit value, the aperture value obtained by the first information calculation unit at the time of imaging is determined as the aperture value of the aperture unit.

  In the camera according to the eleventh aspect, the lower limit storage unit stores an externally input value as an aperture lower limit that is a lower limit of the aperture. The aperture determination unit determines the aperture lower limit value as the aperture value of the aperture unit during imaging when the aperture value obtained by the first information computation unit exceeds the aperture lower limit value, and the aperture value obtained by the first information computation unit Is equal to or smaller than the lower limit value of the aperture, the aperture value obtained by the first information calculation unit during imaging is determined as the aperture value of the aperture unit.

  In the camera of the twelfth aspect, the first information calculation unit obtains a smaller aperture value as the distance information increases.

In the camera according to the first aspect, by including the first information calculation unit, the aperture value of the aperture unit can be determined according to the change in the distance to the subject.
According to another aspect of the camera of the present invention, the aperture value obtained by the first information calculation unit becomes smaller as the distance to the subject becomes longer, and becomes larger as the distance to the subject becomes shorter. Therefore, the aperture determination unit determines the aperture value to be a small value when imaging a subject located at a long distance from the imaging unit based on the aperture value obtained by the first information calculation unit, and is positioned at a short distance from the imaging unit. A large aperture value is determined when an object to be imaged is captured. For this reason, when an object located at a long distance from the imaging unit is imaged, the exposure amount of the imaging unit is prevented from being insufficient, and an image with appropriate exposure can be obtained.

In the camera according to the fourth aspect, by including the first information calculation unit, the aperture value of the aperture unit can be determined according to the distance to the subject and the preliminary light emission amount.
In the camera according to claim 5, the aperture value obtained by the first information calculation unit becomes smaller as the preliminary light emission amount of the illumination device is smaller and the distance to the subject is longer. Generally, the smaller the preliminary light emission amount of the lighting device, the smaller the main light emission amount (light emission amount of the lighting device during imaging) of the lighting device. In other words, the smaller the preliminary light emission amount, the lower the amount of light (the exposure amount of the image pickup unit) that the reflected light from the subject by the main light emission of the illumination device enters the image pickup unit. The aperture determination unit determines the aperture value to be smaller as the light emission amount of the illumination device is smaller when imaging a subject located at a long distance from the imaging unit based on the aperture value obtained by the first information calculation unit. it can. For this reason, when an object located at a long distance from the imaging unit is imaged, the exposure amount of the imaging unit is prevented from being insufficient, and an image with appropriate exposure can be obtained.

In the camera according to the seventh aspect, by including the first information calculation unit, the aperture value of the aperture unit can be determined according to the distance to the subject and the state of the illumination device (whether or not the bounce state is set).
According to another aspect of the camera of the present invention, the aperture value obtained by the first information calculation unit becomes smaller as the lighting device is in the bounce state and the distance to the subject is longer. In general, in the bounce state, the subject is irradiated with indirect light (bounce emission) that reflects the flash emission on the ceiling, wall, etc., so the subject by the irradiated light is more than when the subject is irradiated directly. The amount of light (the exposure amount of the image pickup unit) that the reflected light from the light enters the image pickup unit decreases. The aperture determination unit can determine the aperture value to be a small value during imaging in which bounce emission is emitted to a subject located at a long distance from the imaging unit, based on the aperture value obtained by the first information calculation unit. For this reason, when an object located at a long distance from the imaging unit is imaged, the exposure amount of the imaging unit is prevented from being insufficient, and an image with appropriate exposure can be obtained.

  In the camera of claim 3, claim 6 and claim 9, the distance information setting unit is configured to change the rate of change before the imaging when the rate of change exceeds a predetermined value, that is, when the distance to the subject changes greatly between imaging and imaging. The distance information is weighted more than the distance information at the time of imaging, and a value closer to the distance information before the imaging than the average value of the distance information before the imaging and the distance information at the time of imaging is set as the distance information. The distance information setting unit weights the pre-imaging distance information smaller than the imaging distance information when the rate of change is equal to or less than a predetermined value, i.e., when the distance to the subject does not change significantly before and during imaging. A value closer to the imaging distance information than the average value of the information and the imaging distance information is set as the distance information. Therefore, the set distance information can be maintained at a substantially constant value. Therefore, it is possible to prevent the obtained aperture value from changing greatly compared to the case where the aperture value is obtained using the pre-imaging distance information or the imaging distance information as it is by the second information calculation unit. For this reason, the aperture value determined by the aperture determination unit is maintained at a substantially constant value. As a result, it is possible to prevent the display that informs the photographer of the determined aperture value from changing frequently, and the photographer can concentrate on the photographing.

  In the camera of the tenth aspect, by providing the upper limit value storage means, the aperture upper limit value can be kept within a range of values that can be set as the aperture value. Therefore, the aperture determination unit can prevent a value extremely larger than the aperture upper limit value stored in the upper limit value storage unit from being determined as the aperture value. As a result, the exposure amount of the imaging unit is prevented from being insufficient, and an image with appropriate exposure can be obtained.

  According to the camera of the eleventh aspect, by providing the lower limit value storage means, the aperture lower limit value can be kept within a range of values that can be set as the aperture value. For this reason, the aperture determination unit can prevent a value extremely smaller than the aperture lower limit value stored in the lower limit value storage unit from being determined as the aperture value. As a result, it is possible to prevent the exposure amount of the imaging unit from being over and the subject image from becoming too bright.

  In the camera according to the twelfth aspect, the aperture value is determined to be a small value when imaging a subject located at a long distance from the imaging unit, and the aperture value is determined to be a large value when imaging a subject located at a short distance from the imaging unit. For this reason, when an object located at a long distance from the imaging unit is imaged, the exposure amount of the imaging unit is prevented from being insufficient, and an image with appropriate exposure can be obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a left side view of the camera 100 according to the first embodiment. The camera 100 is, for example, a single-lens flex-type digital camera, and has a camera body 102.
The photographing lens 104 is detachably attached to a lens mount 10 formed on the front surface of the camera body 102 in order to guide incident light from a subject to the camera body 102. The flash light emitting device 106 is detachably attached to the hot shoe 12 formed on the upper surface of the camera body 102 in order to irradiate the subject with irradiation light. The lens mount 10 and the hot shoe 12 are communication contacts for exchanging various kinds of information between the camera body 102 and the photographing lens 104, and for exchanging various kinds of information between the camera body 102 and the flash light emitting device 106. Each communication contact is provided.

The camera body 102 includes a quick turn mirror 14, a finder screen 16, a penta roof prism 18, an eyepiece lens 20, a photometric re-imaging lens 22, a photometric sensor 24, a shutter 26, a CCD 28, a gain circuit 42 and an A / D in FIG. A conversion circuit 44 is provided.
The quick turn mirror 14 is rotatably provided on the optical axis OA. The quick turn mirror 14 is disposed at an oblique position with respect to the optical axis OA when the subject is not photographed. At the time of non-photographing, the quick turn mirror 14 receives a light beam incident on the camera body 102 from the subject via the photographing lens 104, reflects the received light beam, and guides it to the finder screen 16.

On the other hand, at the time of imaging for imaging a subject, the quick turn mirror 14 is retracted to a position indicated by a broken line in the figure by rotation. At the time of retraction, the light beam incident on the camera body 102 from the subject is guided to the CCD 28 via the shutter 26.
The finder screen 16 diffuses the light beam guided by the quick turn mirror 14 during non-imaging, and guides the diffused light beam to the penta roof prism 18. The penta roof prism 18 reflects a part of the light beam diffused by the finder screen 16 and guides it to the eyepiece lens 20. The penta roof prism 18 reflects another part of the light beam diffused by the finder screen 16 and guides it to the re-imaging lens 22 for photometry.

The eyepiece 20 forms a light beam guided by the penta roof prism 18 as a subject image. The photographer can determine the composition or frame of the subject by looking at the subject image formed by the eyepiece 20.
The photometric re-imaging lens 22 images the light beam guided by the penta roof prism 18 on the photometric sensor 24. The photometric sensor 24 is composed of a light receiving element such as a CCD, for example. The photometric sensor 24 photoelectrically converts the light beam imaged by the photometric re-imaging lens 22 as exposure amount information E indicating the exposure amount per unit time of the photometric sensor 24, and the photoelectrically converted exposure amount information E The data is output to the A / D conversion circuit 44.

  The shutter 26 has a shutter film (not shown) disposed at a position that blocks the optical path from the lens system 30 of the photographing lens 104 to the CCD 28. The shutter 26 is driven by a shutter driver (not shown), and adjusts the time during which the CCD 28 is exposed by the light beam incident on the camera body 102 from the lens system 30. The shutter film is opened to secure an optical path from the lens system 30 to the CCD 28 during imaging.

The CCD 28 is disposed at a position facing the lens system 30 through the shutter 26. The CCD 28 is driven by a CCD driver (not shown), photoelectrically converts the subject image formed by the lens system 30, and outputs the photoelectrically converted subject image to the gain circuit 42.
The taking lens 104 has a lens system 30 and a diaphragm 32. The lens system 30 includes a plurality of lenses including a focus lens that focuses on a subject and a zoom lens that zooms the subject image. The position of the focus lens and zoom lens in the optical axis direction is adjusted by a lens driving circuit (not shown). The diaphragm 32 is driven by a diaphragm driver (not shown). The aperture value FNo of the aperture 32 is adjusted so as to reduce the amount of light that has passed through the lens system 30.

The flash light emitting device 106 includes a light emitting portion 34, a shaft portion 36, a mounting portion 38 and a main body portion 40. The light emitting unit 34 is disposed so as to be rotatable in the vertical direction in the figure with the shaft 36 as a center. The light emitting unit 34 includes a capacitor, a transformer, a discharge tube, and the like (not shown).
In order to irradiate the subject with the irradiation light, the light emitting unit 34 generates a voltage using a capacitor and a transformer, and applies the generated voltage to the discharge tube to flash the discharge tube. In the bounce state in which the subject is irradiated with indirect light (bounce light emission) in which flash light is reflected on the ceiling, floor, or the like, the light emitting unit 34 is directed to the bounce surface of the ceiling or floor by rotation. The attachment portion 38 is disposed below the main body portion 40 and is detachably attached to the hot shoe 12 of the camera main body 102.

  FIG. 2 shows the internal configuration of the camera body 102, the photographing lens 104, and the flash light emitting device 106 shown in FIG. The camera body 102 includes a photometric sensor 24, a CCD 28, a gain circuit 42, an A / D conversion circuit 44, an amplification factor adjustment circuit 46, a CPU 48, an operation unit 50, a RAM 52, and an LCD (Liquid Crystal Display). Note that elements such as a shutter mechanism and a mirror mechanism are not shown.

The gain circuit 42 is controlled by the CPU 48 via the amplification factor adjustment circuit 46. The gain circuit 42 amplifies the analog amount received from the CCD 28 with a variable amplification factor. The amplification factor adjustment circuit 46 adjusts the amplification factor of the gain circuit 42 according to a predetermined ISO sensitivity (for example, ISO 100).
The A / D conversion circuit 44 A / D converts the exposure amount information E received from the photometry sensor 24 and outputs the A / D converted exposure amount information E to the CPU 48. The A / D conversion circuit 44 A / D converts the subject image received from the CCD 28 and outputs the A / D converted image data to the CPU 48.

  The CPU 48 is connected to the CPU 56 and the CPU 62 via each communication contact described in FIG. The CPU 48 has a ROM 52 built therein. The ROM 52 is configured by, for example, an EEPROM or a flash memory that can electrically rewrite data, and retains data even when the camera 100 is turned off. The ROM 52 stores programs executed by the CPU 48 and imaging information of the CCD 28 (ISO sensitivity, exposure time of the electronic shutter, white balance correction value, etc.).

  The operation unit 50 can change a main power switch for turning on / off the power of the camera body 102, a shutter switch pressed by a photographer when photographing a subject, a “shooting mode” for photographing a subject, a language setting, and a date / time setting. Various switches (not shown) including a selection switch for selecting various modes such as a “setup mode” and an “auto focus mode” for focusing on a subject and an image, etc. are provided.

  The RAM 52 temporarily stores image data captured by the CCD 28, distance information Xmm (described later), and the like. The LCD is driven by an LCD driver (not shown) and displays an image captured by the CCD 28 and various mode setting screens before and after the shutter switch is pressed down. That is, the LCD is also used as a viewfinder that displays an image formed by the lens system 30 of the photographing lens 104. The photographer can determine the composition and the like of the subject by looking at the image displayed on the LCD.

The photographing lens 104 includes a lens system 30, an aperture 32, a CPU 56, an encoder (not shown) that detects a photographing distance Xmm (described later) of the lens system 30, and the like. The CPU 56 has a built-in ROM 58. The ROM 58 stores lens information unique to the photographing lens 104 such as an open aperture value of the lens, a focal length, and an exit pupil distance error.
The CPU 56 outputs the distance information Xmm detected by the encoder to the CPU 48 via the communication contact described in FIG. In this example, the distance information Xmm indicates information indicating the distance from the imaging surface of the CCD 28 of the camera body 102 to the subject in units of meters.

The flash light emitting device 106 includes a light emitting unit 34, a light emission control circuit 60, a CPU 62, a booster circuit and an operation unit (not shown) and the like. The light emission control circuit 60 receives light emission information indicating the light emission amount and the number of times of light emission of the light emitting unit 34 from the CPU 62, and causes the light emitting unit 34 to flash light based on the received light emission information.
The CPU 62 has a built-in ROM 64. The ROM 64 stores information unique to the flash light emitting device 106 such as a guide number indicating the magnitude of the main light emission amount (the light emission amount of the light emitting unit 34 at the time of imaging) and the synchronization time (tuning time). For example, the CPU 62 sends the minimum guide number GMINin indicating the minimum light emission amount of the light emitting unit 34 and the bounce information BI indicating that the state of the light emitting unit 34 is the bounce state to the CPU 48 via the communication contact described in FIG. Output.

  In this example, the CPU 48 is used to adjust the gain of the gain circuit 42 when the subject is imaged without using the flash light emitting device 106, that is, when the flash light emitting device 106 is not attached to the camera body 102. In accordance with a program diagram (FIG. 3) using sensitivity information ISO indicating ISO sensitivity and exposure amount information E received from the A / D conversion circuit 44, the shutter speed SS of the shutter 26 (FIG. 1) and the photographing lens 104 A combination with the aperture value FNo of the aperture 32 is determined.

  On the other hand, the CPU 48 receives and receives the distance information Xmm from the CPU 56 via the communication contact when the subject is imaged using the flash light emitting device 106, that is, when the flash light emitting device 106 is attached to the camera body 102. An aperture limit value AvL (Aperture Value Limit) that is an APEX (Additive System of Photographic Exposure) value corresponding to the aperture value FNo is calculated using the distance information Xmm and the sensitivity information ISO.

  FIG. 3 shows an example of a program diagram used when determining the combination of the shutter speed SS and the aperture value FNo. The horizontal and vertical axes in the figure indicate the shutter speed SS and the aperture value FNo, respectively, and the diagonal lines in the figure indicate the same exposure value EV (described later). The bold line in the figure shows the program diagram used in this embodiment. In the present invention, the exposure value EV indicates the exposure value of the CCD 28 that is predetermined in the program diagram.

  As described in FIG. 2, when the subject is imaged without using the flash light emitting device 106, the CPU 48 determines a combination of the shutter speed SS and the aperture value FNo using a program diagram. Specifically, the CPU 48 converts the sensitivity information ISO and the exposure amount information E into APEX units of the same dimension. Next, the CPU 48 calculates the luminance value BV of the subject using the imaging sensitivity SV, which is the APEX value of the sensitivity information ISO, and the photometric value LV, which is the APEX value of the exposure amount information E, and uses the calculated luminance value BV. Store in the RAM 52. In this example, the CPU 48 calculates the luminance value BV using the following arithmetic expression (1).

BV = LV-SV (1)
When the stored brightness value BV is, for example, 9.7, the CPU 48 determines the intersection of the oblique line indicating the exposure value EV = 9.7 and the bold line (program diagram) of the shutter speed SS and the aperture value FNo. Determine as a combination. In this example, the combinations corresponding to the intersections in the figure are the shutter speed SS = 1/30 (seconds) and the aperture value FNo = f2.8. This combination is determined as the shutter speed SS and the aperture value FNo for keeping the brightness of the subject optimal during imaging without using the flash light emitting device 106.

4 and 5 show the determination operation of the aperture value FNo and the shutter speed SS in the first embodiment of the camera. The operations shown in FIGS. 4 and 5 are realized by the CPU 48 executing a program stored in the ROM 52.
First, in step S100, when the photographer receives a setup mode screen display request from the photographer, the CPU 48 displays a menu screen for setting the upper limit value SMax and the lower limit value SMin on the LCD. In the present invention, the upper limit value SMax and the lower limit value SMin indicate the upper limit value and the lower limit value of the aperture limit value AvL, respectively. Thereafter, the process proceeds to step S102.

In step S <b> 102, the CPU 48 stores the upper limit value SMax and the lower limit value SMin set by the photographer in the RAM 52. As described above, the upper limit value SMax and the lower limit value SMin can be set within the range of values that can be set as the aperture limit value AvL (for example, 1.0 to 6.0). Thereafter, the process proceeds to step S104.
In step S <b> 104, when the CPU 48 receives a shooting mode selection request from the photographer, the CPU 48 calculates the brightness value BV using the arithmetic expression (1) described in FIG. 3 and stores the calculated brightness value BV in the RAM 52. Thereafter, the process proceeds to step S106.

In step S <b> 106, the CPU 48 detects whether or not the flash light emitting device 106 is attached to the hot shoe 12. If it is detected that the flash light emitting device 106 is attached, the process proceeds to step S108. If it is detected that the flash light emitting device 106 is not attached, the process proceeds to step S110.
In step S108, the CPU 48 calculates the aperture limit value AvL using the distance information Xmm and the sensitivity information ISO as described in FIG. 2, and stores the calculated aperture limit value AvL in the RAM 52. In this example, the CPU 48 calculates the aperture limit value AvL using the following arithmetic expression (2). In the calculation formula (2), NSBC indicates a constant for adjusting the aperture limit value AvL. Xv represents log ₂ (distance information Xmm).

AvL = NSBC + (SV-5) / 2−Xv (2)
The aperture limit value AvL calculated at this time becomes smaller as the distance from the CCD 28 to the subject becomes longer, and becomes larger as the distance from the CCD 28 to the subject becomes shorter. Therefore, based on the calculated aperture limit value AvL, the CPU 48 sets the aperture value FNo of the aperture 32 when imaging a subject located at a long distance from the camera body 102 (for example, when imaging using a wide-angle lens or a telephoto lens). A small value is determined, and the aperture value FNo of the aperture 32 is determined to be a large value when an object located at a short distance from the CCD 28 is captured (for example, when an image is captured using a macro lens). That is, the CPU 48 can set the aperture value FNo to be smaller when imaging a subject located at a long distance from the CCD 28 than when imaging a subject located at a short distance from the CCD 28. Thereafter, the process proceeds to step S112 in FIG.

On the other hand, in step S110, as described in FIG. 3, the CPU 48 determines the intersection of the oblique line indicating the exposure value EV corresponding to the luminance value BV and the program diagram, the shutter speed SS of the shutter 26 and the aperture value of the aperture 32. The combination of FNo is determined, and the determined combination is stored in the RAM 52. Thereafter, the process proceeds to step S126 in FIG.
In step S112, the CPU 48 detects whether or not the aperture limit value AvL exceeds the upper limit value SMax. If it is detected that the upper limit value SMax is exceeded, the process proceeds to step S114. If it is detected that the value is less than or equal to the upper limit value SMax, the process proceeds to step S116.

  In step S114, the CPU 48 replaces the aperture limit value AvL with the upper limit value SMax and stores it in the RAM 52. As described above, the CPU 48 can prevent a value (for example, 11.0) extremely larger than the upper limit value SMax (for example, 6.0) from being stored in the RAM 52 as the aperture limit value AvL. That is, it is possible to prevent the aperture value FNo corresponding to a value (for example, 11.0) extremely larger than the upper limit value SMax (for example, 6.0) from being determined as the aperture value FNo of the aperture 32. For this reason, it is prevented that the exposure amount of the CCD 28 is insufficient, and an image with appropriate exposure can be obtained. Thereafter, the process proceeds to step S116.

In step S116, the CPU 48 detects whether or not the aperture limit value AvL is less than or equal to the lower limit value SMin. If it is detected that the value is less than or equal to the lower limit value SMin, the process proceeds to step S118. If it is detected that the lower limit value SMin is exceeded, the process proceeds to step S120.
In step S118, the CPU 48 replaces the aperture limit value AvL with the lower limit value SMin and stores it in the RAM 52. As described above, the CPU 48 can prevent a value (for example, 0) extremely smaller than the lower limit value SMin (for example, 1.0) from being stored in the RAM 52 as the aperture limit value AvL. That is, it is possible to prevent the aperture value FNo corresponding to a value (for example, 0) extremely smaller than the lower limit value SMin (for example, 1.0) from being set as the aperture value FNo of the aperture 32. For this reason, it is possible to prevent the exposure amount of the CCD 28 from becoming excessively large and obtain an image with appropriate exposure. Thereafter, the process proceeds to step S120.

In step S120, as described with reference to FIG. 3, the CPU 48 determines the intersection of the oblique line indicating the exposure value EV corresponding to the luminance value BV and the program diagram with the shutter speed SS of the shutter 26 and the aperture value FNo of the aperture 32. The combination is determined, and the determined combination is stored in the RAM 52. Thereafter, the process proceeds to step S122.
In step S122, the CPU 48 detects whether or not the APEX value corresponding to the aperture value FNo determined using the program diagram is equal to or smaller than the aperture limit value AvL. If it is detected that the value is equal to or smaller than the aperture limit value AvL, the process proceeds to step S124. If it is detected that the aperture limit value AvL is exceeded, the process proceeds to step S126.

In step S124, the CPU 48 replaces the aperture value FNo corresponding to the aperture limit value AvL with the aperture value FNo already determined using the program diagram and stores it in the RAM 52. Thereafter, the process proceeds to step S126.
After the combination of the shutter speed SS and the aperture value FNo is stored in the RAM 52 in step S110 in FIG. 4 or the aperture value FNo corresponding to the aperture limit value AvL is stored in the RAM 52 in step S124, in step S126, The CPU 48 waits for the photographer to press down the shutter switch. If the pressing of the shutter switch is detected, the process proceeds to step S128. If pressing of the shutter switch is not detected, the process proceeds to step S106 in FIG.

  In step S128, the CPU 48 controls the CCD driver, shutter driver and aperture driver, light emission control circuit 60, and the like, respectively, and based on the combination of the shutter speed SS and aperture value FNo stored in the RAM 52, the CCD 28, shutter 26, The diaphragm 32 and the light emitting unit 34 are driven to image the subject. Then, the determination operation of the aperture value FNo and the shutter speed SS in the first embodiment of the camera ends.

  FIG. 6 shows the relationship between the distance information Xmm and the aperture limit value AvL. The horizontal and vertical axes in the figure indicate distance information Xmm (m) and the aperture limit value AvL, respectively. Each hatched line in the drawing indicates the aperture limit value AvL stored in the RAM 52 in FIGS. 4 and 5. In the figure, rhombuses, squares, triangles, and diagonal lines with crosses indicate aperture limit values AvL corresponding to ISO 200, ISO 400, ISO 800, and ISO 1600, respectively. In this example, the upper limit SMax and the lower limit SMin are set to 6.0 and 1.0 (for example, the open F value), respectively.

  As described with reference to FIGS. 4 and 5, when imaging a subject located at a short distance from the CCD 28 (distance information Xmm = 0.50 m to 1.00 m in the figure), the aperture value FNo determined using the program diagram is set. When the corresponding APEX value (for example, 5.5) is equal to or less than the upper limit value SMax (= 6.0), the aperture value FNo of the aperture 32 is set as the aperture value FNo corresponding to the upper limit value SMax (= 6.0). It is determined. For this reason, it is possible to prevent the aperture value FNo of the aperture 32 from becoming smaller than the aperture value FNo corresponding to the upper limit value SMax (= 6.0). Therefore, the area of the entrance pupil where the reflected light from the subject due to the flash emission of the light emitting unit 34 enters the CCD 28 can be kept below a certain size. For this reason, overexposure of the CCD 28 is prevented, and an image with proper exposure can be obtained.

  On the other hand, when an image of a subject located at a long distance from the CCD 28 (distance information Xmm = 11.31 to 2.00 in the figure) is captured, the APEX value (for example, 0.00.) Corresponding to the aperture value FNo determined using the program diagram. When 5) is less than or equal to the lower limit value SMin (= 1.0), the aperture value FNo of the aperture 32 is determined as the aperture value FNo corresponding to the lower limit value SMin (= 1.0). Generally, the minimum value of the APEX value corresponding to the aperture value FNo determined using the program diagram is very small compared to the lower limit value SMin (= 1.0). For this reason, it is possible to prevent the aperture value FNo of the aperture 32 from becoming larger than the aperture value FNo corresponding to the lower limit value SMin (= 1.0). Therefore, the area of the entrance pupil where the reflected light from the subject due to the flash emission of the light emitting unit 34 enters the CCD 28 can be maintained at a certain size or more. For this reason, insufficient exposure of the CCD 28 is prevented, and an image with proper exposure can be obtained. The shutter speed SS is set to a value smaller than the sync time described in FIG.

  As described above, in the first embodiment, the CPU 48 can set the aperture value FNo smaller when imaging a subject located at a long distance from the CCD 28 than when imaging a subject located at a short distance from the CCD 28. In general, the area of the entrance pupil that is the entrance to the CCD 28 of the reflected light from the subject by the flash emission of the light emitting unit 34 of the flash light emitting device 106 is inversely proportional to the square of the aperture value FNo. For this reason, when the subject located at a long distance from the CCD 28 is imaged using the flash light emitting device 106, the area of the entrance pupil where the reflected light from the subject due to the flash emission of the light emitting unit 34 enters the CCD 28 can be increased. As a result, when the subject located at a long distance from the CCD 28 is imaged, the exposure amount of the CCD 28 is prevented from being insufficient, and an image with appropriate exposure can be obtained.

  7 and 8 show an operation for determining the aperture value FNo and the shutter speed SS in the second embodiment of the camera. Detailed descriptions of the same elements as those described in the first embodiment of the camera are omitted. In this embodiment, the program stored in the ROM 52 for execution by the CPU 48 shown in FIG. 2 is different from that of the first embodiment of the camera. Other configurations are the same as those in the first embodiment of the camera shown in FIGS. 7 and 8 are the same as FIGS. 4 and 5 except that step S108 of the first embodiment (FIGS. 4 and 5) is replaced with steps S200 to S212.

Detailed description of the same processing as in FIGS. 4 and 5 described above is omitted. 7 and 8 is realized by the CPU 48 executing a program stored in the ROM 52. After steps S100 to S106 are executed, the process proceeds to step S110 or step S200.
In step S200, the CPU 48 acquires the distance information Xmm1 from the CPU 56 via the communication contact, and stores the acquired distance information Xmm1 in the RAM 52. In the present invention, the distance information Xmm1 indicates the distance information Xmm acquired from the CPU 56 by the CPU 48 before half-pressing of the shutter switch. Thereafter, the process proceeds to step S202.

In step S202, the CPU 48 waits for the photographer to half-press the shutter switch. If half-pressing of the shutter switch is detected, the process proceeds to step S204. Step S202 is repeated until half-pressing of the shutter switch is detected.
In step S204, the CPU 48 acquires the distance information Xmm2 from the CPU 56 via the communication contact, and stores the acquired distance information Xmm2 in the RAM 52. In the present invention, the distance information Xmm2 indicates the distance information Xmm acquired from the CPU 56 by the CPU 48 after half-pressing of the shutter switch. Thereafter, the process proceeds to step S206.

In step S206, the CPU 48 calculates an increase rate P (%) of the distance information Xmm2 with respect to the distance information Xmm1, and detects whether the calculated increase rate P (%) exceeds a predetermined value V. In this example, the CPU 48 calculates the increase rate P (%) using the following arithmetic expression (3).
P (%) = {(Xmm2-Xmm1) / Xmm1} × 100 (3)
If it is detected that the predetermined value V is exceeded, the process proceeds to step S208. When it is detected that the predetermined value V is not exceeded, the process proceeds to step S210.

In step S <b> 208, the CPU 48 calculates distance information XvC using the following arithmetic expression (4), and stores the calculated distance information XvC in the RAM 52. In the arithmetic expression (4), Xv and XvCOLd indicate log ₂ (Xmm1) and log ₂ (Xmm2), respectively. K (0 ≦ K ≦ 1) is a weighting constant for determining the weighting of Xv and XvCOLd.

XvC = K × Xv + (1−K) × XvCOLd (4)
In this example, the distance information XvC is calculated as K = 0.8. Thereafter, the process proceeds to step S212.
On the other hand, when the increase rate P (%) does not exceed the predetermined value V in step S206, in step S210, the CPU 48 calculates the distance information XvC using the arithmetic expression (4), and the calculated distance information XvC is stored in the RAM 52. To store. In this example, the distance information XvC is calculated as K = 0.2.

  As described above, the CPU 48 determines that the distance information Xmm1 is larger than the distance information Xmm2 when the increase rate P (%) exceeds the predetermined value V, that is, when the distance information Xmm changes greatly before and after the shutter switch is pressed down. By multiplying by the weight constant K, a value closer to the distance information Xmm1 than the average value of the distance information Xmm1 and the distance information Xmm2 is calculated as the distance information XvC. When the increase rate P (%) is equal to or less than the predetermined value V, that is, when the distance information Xmm does not change significantly before and after the shutter switch is pressed down, the CPU 48 adds a weight constant K smaller than the distance information Xmm2 to the distance information Xmm1. , And a value closer to the distance information Xmm2 than the average value of the distance information Xmm1 and the distance information Xmm2 is calculated as the distance information XvC. Therefore, the distance information XvC can be maintained at a substantially constant value. In particular, when the setting of the autofocus mode described in FIG. 2 is a continuous mode in which the subject is always in focus while the shutter switch is half-pressed, that is, when the distance information Xmm2 always changes, the distance information XvC By calculating the aperture limit value AvL using, it is possible to prevent the aperture limit value AvL from changing greatly. Thereafter, the process proceeds to step S212.

In step S212, the CPU 48 calculates the aperture limit value AvL using the distance information XvC and the sensitivity information ISO, and stores the calculated aperture limit value AvL in the RAM 52. In this example, the CPU 48 calculates the aperture limit value AvL using the following arithmetic expression (5). In the calculation formula (5), NSBC indicates a constant for adjusting the aperture limit value AvL.
AvL = NSBC + (SV-5) / 2−XvC (5)
Thereafter, after the processing of steps S112 to S128 in FIG. 8 is executed, the determination operation of the aperture value FNo and the shutter speed SS in the second embodiment of the camera is completed.

  As described above, in the second embodiment, the same effect as that of the first embodiment can be obtained. Furthermore, it is possible to prevent the calculated aperture limit value AvL from changing greatly compared to the case where the aperture limit value AvL is calculated using the distance information Xmm1 or the distance information Xmm2 as it is. For this reason, it is possible to prevent the aperture limit value AvL from being frequently lower than the upper limit value SMax or exceeding the lower limit value SMin. As a result, the LCD display screen that informs the photographer of the aperture value FNo corresponding to the aperture limit value AvL is prevented from frequently changing, and the photographer can concentrate on photographing.

  9 and 10 show the determination operation of the aperture value FNo and the shutter speed SS in the third embodiment of the camera. Detailed descriptions of the same elements as those described in the first embodiment of the camera are omitted. In this embodiment, the program stored in the ROM 52 for execution by the CPU 48 shown in FIG. 2 is different from that of the first embodiment of the camera. Other configurations are the same as those in the first embodiment of the camera shown in FIGS. 9 and 10 are the same as FIGS. 7 and 8 except that step S212 in the second embodiment (FIGS. 7 and 8) is replaced with step S300.

Detailed description of the same processing as in FIGS. 7 and 8 described above is omitted. The operations shown in FIGS. 9 and 10 are realized by the CPU 48 executing the program stored in the ROM 52. After steps S100 to S106 and steps S200 to S210 are executed, the process proceeds to step S300.
In step S300, the CPU 48 calculates the aperture limit value AvL using the distance information XvC, the sensitivity information ISO, and the minimum guide number GNMin described in FIG. 2, and stores the calculated aperture limit value AvL in the RAM 52. In this example, the CPU 48 calculates the aperture limit value AvL using the following arithmetic expression (6). In the calculation formula (6), GvMon is a logarithmic value of the minimum guide number GNMin. SSBC indicates a constant for adjusting the aperture limit value AvL.

AvL = GvMon + SSBC + (SV-5) / 2−XvC (6)
Thus, the aperture limit value AvL becomes smaller as the minimum guide number GNMin is smaller and the distance information XvC is larger (the subject is located far from the CCD 28). Generally, the smaller the minimum guide number GNMin, the smaller the main light emission amount of the light emitting unit 34 described in FIG. In other words, the smaller the minimum guide number GNMin, the lower the amount of light (the exposure amount of the CCD 28) that the reflected light from the subject by the main emission of the light emitting unit 34 enters the CCD 28. The CPU 48 can determine the aperture limit value AvL (the aperture value FNo of the aperture 32) to be a smaller value as the minimum guide number GMINin is smaller when imaging a subject located at a long distance from the CCD 28.

Thereafter, after the processing of steps S112 to S128 in FIG. 10 is executed, the determination operation of the aperture value FNo and the shutter speed SS in the third embodiment of the camera is completed.
As described above, in the third embodiment, the same effect as in the first embodiment can be obtained. Further, the CPU 48 can determine the aperture limit value AvL (the aperture value FNo of the aperture 32) as a smaller value as the minimum guide number GNmin is smaller when imaging a subject located at a long distance from the CCD 28. For this reason, when an object located at a long distance from the CCD 28 is imaged, the exposure amount of the CCD 28 is prevented from being insufficient, and an image with appropriate exposure can be obtained.

  FIGS. 11 and 12 show the determination operation of the aperture value FNo and the shutter speed SS in the fourth embodiment of the camera. Detailed description of the same elements as those described in the first embodiment of the camera is omitted. In this embodiment, the program stored in the ROM 52 for execution by the CPU 48 shown in FIG. 2 is different from that of the first embodiment of the camera. Other configurations are the same as those of the first embodiment of the camera shown in FIGS. 11 and 12 are the same as FIGS. 7 and 8 except that step S212 of the second embodiment (FIGS. 7 and 8) is replaced by steps S400 to S404.

Detailed description of the same processing as in FIGS. 7 and 8 described above is omitted. Also, the operations shown in FIGS. 11 and 12 are realized by the CPU 48 executing a program stored in the ROM 52. After steps S100 to S106 and steps S200 to S210 are executed, the process proceeds to step S400.
In step S400, when the CPU 48 acquires the bounce information BI from the CPU 56 via the communication contact (the state of the light emitting unit 34 is the bounce state), the process proceeds to step 402. If the bounce information BI is not acquired (the state of the light emitting unit 34 is not the bounce state), the process proceeds to step S404.

  In step S402, the CPU 48 calculates the aperture limit value AvL using the distance information XvC, the sensitivity information ISO, and the constant BSBC, and stores the calculated aperture limit value AvL in the RAM 52. In this example, the CPU 48 calculates the aperture limit value AvL using the following arithmetic expression (7). In the calculation formula (7), BSBC indicates a constant for adjusting the aperture limit value AvL when the state of the light emitting unit 34 of the flash light emitting device 106 is a bounce state. SSBC indicates a constant for adjusting the aperture limit value AvL.

AvL = SSBC + (SV-5) / 2-XvC + BSBC (7)
As described above, the aperture limit value AvL is smaller as the state of the light emitting unit 34 is in the bounce state and the distance information XvC is larger (the subject is located at a longer distance from the CCD 28). In general, in the bounce state, the subject is irradiated with indirect light (bounce emission) that reflects the flash emission on the ceiling, wall, etc., so the subject by the irradiated light is more than when the subject is irradiated directly. The amount of light (the exposure amount of the image pickup unit) that the reflected light from the light enters the image pickup unit decreases. The CPU 48 can determine the aperture limit value AvL (the aperture value FNo of the aperture 32) to a small value at the time of imaging in which bounce light emission is irradiated to a subject located at a long distance from the CCD 28.

Thereafter, after the processing of steps S112 to S128 in FIG. 12 is executed, the determination operation of the aperture value FNo and the shutter speed SS in the fourth embodiment of the camera is completed.
As described above, in the fourth embodiment, the same effect as in the first embodiment can be obtained. Further, the CPU 48 can determine the aperture limit value AvL (the aperture value FNo of the aperture 32) to a small value during imaging in which bounce light emission is irradiated to a subject located at a long distance from the CCD 28. For this reason, when an object located at a long distance from the CCD 28 is imaged, the exposure amount of the CCD 28 is prevented from being insufficient, and an image with appropriate exposure can be obtained.

In the first embodiment described above, the CPU 48 has described an example in which the aperture limit value AvL is calculated by the arithmetic expression (2) using Xv (= log ₂ (distance information Xmm)). The present invention is not limited to such an embodiment. The CPU 48 may calculate the aperture limit value AvL by the arithmetic expression (2) using Xv calculated by using the following conditional expression (8). In the conditional expression (8), fv represents log ₂ (fmm / 50). Note that fmm is lens information indicating the focal length (mm) stored in the ROM 58 of the photographing lens 104, and fv is 0 when the focal length (mm) is 50 mm.

If Xv> log ₂ (50) + fv−2 Xv = log ₂ (50) + fv−2 (8)
For example, when imaging a subject using a wide-angle lens as the photographing lens 104, the depth of field becomes deep, and thus the CPU 48 may not be able to accurately acquire the distance information Xmm (m) from the CPU 56. Specifically, for example, when the distance to the subject is 3 m and the next is infinite, the acquired distance information Xmm is acquired as infinite if it exceeds 3 m. In the present invention, when Xv exceeds log ₂ (50) + fv−2, Xv can be set to log ₂ (50) + fv−2. For example, by setting log ₂ (50) + fv−2 to log ₂ (3 m), it is possible to prevent Xv from being set to a value larger than log ₂ (3 m) (inaccurate value).

In the first to fourth embodiments described above, the example in which the subject is imaged using the CCD 28 has been described. The present invention is not limited to such an embodiment. The subject may be imaged using an image sensor other than the CCD, for example, a CMOS image sensor or other amplification type solid-state image sensor.
In the first to fourth embodiments described above, an example in which a single-lens flex type camera capable of attaching the photographing lens 104 to the camera body 102 is used as the camera 100 has been described. The present invention is not limited to such an embodiment. A compact type camera in which a photographing lens is integrated may be used.

In the first to fourth embodiments described above, an example in which a digital camera is used as the camera 100 has been described. The present invention is not limited to such an embodiment. A silver film type camera may be used as the camera 100.
In the first to fourth embodiments described above, the CPU 48 described an example in which the aperture limit value AvL is calculated using the imaging sensitivity SV in the arithmetic expressions (2), (5), (6), and (7). . The present invention is not limited to such an embodiment. The CPU 48 may calculate the aperture limit value AvL using a predetermined constant instead of the imaging sensitivity SV in the arithmetic expressions (2), (5), (6), and (7).

  As mentioned above, although this invention was demonstrated in detail, said embodiment and its modification are only examples of this invention, and this invention is not limited to this. Obviously, modifications can be made without departing from the scope of the present invention.

  The present invention is applied to a camera that automatically sets a combination of a diaphragm aperture value and an exposure time.

It is a block diagram which shows 1st Embodiment of the camera of this invention. It is a block diagram which shows the internal structure of the camera main body, imaging lens, and flash light-emitting device which were shown in FIG. It is a figure which shows an example of the program diagram used at the time of determination of the combination of a shutter speed and an aperture value. It is a flowchart which shows the determination operation | movement of the aperture value and shutter speed in 1st Embodiment of the camera of this invention. It is a flowchart which shows the determination operation | movement of the aperture value and shutter speed in 1st Embodiment of the camera of this invention. It is a figure which shows the relationship between distance information and an aperture limit value. It is a flowchart which shows the determination operation | movement of the aperture value and shutter speed in 2nd Embodiment of the camera of this invention. It is a flowchart which shows the determination operation | movement of the aperture value and shutter speed in 2nd Embodiment of the camera of this invention. It is a flowchart which shows the determination operation | movement of the aperture value and shutter speed in 3rd Embodiment of the camera of this invention. It is a flowchart which shows the determination operation | movement of the aperture value and shutter speed in 3rd Embodiment of the camera of this invention. It is a flowchart which shows the determination operation | movement of the aperture value and shutter speed in 4th Embodiment of the camera of this invention. It is a flowchart which shows the determination operation | movement of the aperture value and shutter speed in 4th Embodiment of the camera of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Lens mount, 12 ... Hot shoe, 14 ... Quick turn mirror, 16 ... Finder screen, 18 ... Penta-dach prism, 20 ... Eyepiece lens, 22 ... Re-imaging lens for photometry, 24 ... Sensor for photometry, 26 ... Shutter, 28 ... CCD, 30 ... Lens system, 32 ... Aperture, 34 ... Light emitting part, 36 ... Shaft part, 38 ... Mounting part, 40 ... Body part, 42 ... Gain circuit, 44 ... A / D conversion circuit, 46 ... Amplification factor Adjustment circuit 48, 56, 62 ... CPU, 50 ... operation unit, 52 ... RAM, 54, 58, 64 ... ROM, 60 ... light emission control circuit, 100 ... camera, 102 ... camera body, 104 ... taking lens, 106 ... Flash light emitting device

Claims (12)

An imaging unit for imaging the subject through a diaphragm and a lens provided on an optical path from the subject to the camera body;
A distance information acquisition unit that acquires distance information indicating the distance to the subject from the lens;
A first information calculation unit for obtaining an aperture value of the aperture unit using the distance information;
An aperture determination unit that determines the aperture value of the aperture unit to the aperture value obtained by the first information calculation unit when the subject is imaged using an illumination device that irradiates the subject with illumination light. A camera characterized by that. The camera of claim 1,
The camera according to claim 1, wherein the first information calculation unit obtains a ratio between imaging information that is information relating to imaging conditions of the imaging unit and the distance information as an aperture value of the aperture unit. The camera of claim 1,
A change rate calculating unit that compares pre-imaging distance information and imaging distance information acquired by the distance information acquisition unit before and during imaging, and calculates a change rate of the imaging distance information with respect to the pre-imaging distance information; and ,
When the rate of change calculated by the rate-of-change calculating unit exceeds a predetermined value, the pre-imaging distance information is weighted more than the imaging distance information, and the average value of the pre-imaging distance information and the imaging distance information is A value close to the pre-imaging distance information is set as the distance information, and when the change rate is equal to or less than a predetermined value, the pre-imaging distance information is weighted smaller than the pre-imaging distance information, and the pre-imaging distance information and the imaging A distance information setting unit that sets a value closer to the imaging distance information than the average value of the time distance information as the distance information;
The first information calculation unit includes a second information calculation unit that obtains the aperture value using distance information set by the distance information setting unit. An imaging unit for imaging the subject through a diaphragm and a lens provided on an optical path from the subject to the camera body;
A distance information acquisition unit that acquires distance information indicating the distance to the subject from the lens;
A light emission information acquisition unit that acquires preliminary light emission information indicating a preliminary light emission amount of the illumination device from an illumination device that irradiates the subject with irradiation light;
A first information calculation unit for obtaining an aperture value of the aperture unit using the preliminary light emission information and the distance information;
A camera comprising: an aperture determination unit that determines an aperture value of the aperture unit to an aperture value obtained by the first information calculation unit when imaging the subject using the illumination device. The camera according to claim 4, wherein
The first information calculation unit obtains a ratio of a product of imaging information, which is information related to imaging conditions of the imaging unit, and the preliminary light emission information, and the distance information as an aperture value of the aperture unit. camera. The camera according to claim 4.
A change rate calculating unit that compares pre-imaging distance information and imaging distance information acquired by the distance information acquisition unit before and during imaging, and calculates a change rate of the imaging distance information with respect to the pre-imaging distance information; and ,
When the rate of change calculated by the rate-of-change calculating unit exceeds a predetermined value, the pre-imaging distance information is weighted more than the imaging distance information, and the average value of the pre-imaging distance information and the imaging distance information is A value close to the pre-imaging distance information is set as the distance information, and when the change rate is a predetermined value or less, the pre-imaging distance information is weighted smaller than the pre-imaging distance information, and the pre-imaging distance information and the imaging A distance information setting unit that sets a value closer to the imaging distance information than the average value of the time distance information as the distance information;
The first information calculation unit includes a second information calculation unit that calculates the aperture value using the preliminary light emission information and the distance information set by the distance information setting unit. An imaging unit for imaging the subject through a diaphragm and a lens provided on an optical path from the subject to the camera body;
A distance information acquisition unit that acquires distance information indicating the distance to the subject from the lens;
A bounce information acquisition unit that acquires bounce information indicating that the subject is in a bounce state in which the subject is indirectly irradiated with the irradiation light from an illumination device that irradiates the subject with irradiation light;
A first information calculation unit for obtaining an aperture value of the aperture unit using the bounce information and the distance information;
An aperture determination unit that determines the aperture value of the aperture unit to the aperture value obtained by the first information calculation unit when the subject is imaged using an illumination device that irradiates the subject with illumination light. A camera characterized by that. The camera according to claim 7, wherein
The first information calculation unit obtains a ratio of a product of imaging information and bounce information, which is information related to imaging conditions of the imaging unit, and the distance information as an aperture value of the aperture unit. . The camera according to claim 7, wherein
A change rate calculating unit that compares pre-imaging distance information and imaging distance information acquired by the distance information acquisition unit before and during imaging, and calculates a change rate of the imaging distance information with respect to the pre-imaging distance information; and ,
When the rate of change calculated by the rate-of-change calculating unit exceeds a predetermined value, the pre-imaging distance information is weighted more than the imaging distance information, and the average value of the pre-imaging distance information and the imaging distance information is A value close to the pre-imaging distance information is set as the distance information, and when the change rate is equal to or less than a predetermined value, the pre-imaging distance information is weighted smaller than the pre-imaging distance information, and the pre-imaging distance information and the imaging A distance information setting unit that sets a value closer to the imaging distance information than the average value of the time distance information as the distance information;
The first information calculation unit includes a second information calculation unit that calculates the aperture value using the bounce information and the distance information set by the distance information setting unit. The camera according to any one of claims 1, 4, and 7,
An upper limit storage unit that stores an externally input value as an aperture upper limit that is an upper limit of the aperture value;
The aperture determination unit determines the aperture upper limit value as the aperture value of the aperture unit during the imaging when the aperture value obtained by the first information calculation unit exceeds the aperture upper limit value, and the first information calculation The aperture value obtained by the first information calculation unit during the imaging is determined as the aperture value of the aperture unit when the aperture value obtained by the unit is equal to or less than the upper limit value of the aperture. The camera according to any one of claims 1, 4, and 7,
A lower limit storage unit for storing an externally input value as an aperture lower limit that is a lower limit of the aperture value;
The aperture determination unit determines the aperture lower limit value as the aperture value of the aperture unit during the imaging when the aperture value obtained by the first information calculation unit is less than or equal to the aperture lower limit value, and the first information When the aperture value obtained by the computing unit exceeds the aperture lower limit value, the aperture value obtained by the first information computing unit at the time of imaging is determined as the aperture value of the aperture unit. The camera according to any one of claims 1, 4, and 7,
The first information calculation unit obtains a smaller aperture value as the distance information becomes larger.

Images