JP5521429B2 - Light emission amount control device and light emission amount control method - Google Patents

Description

  The present invention relates to a light emission amount control device and a light emission amount control method.

  Conventionally, in an imaging device such as a digital camera equipped with a flash device, preliminary light emission of the flash device is performed prior to shooting, and reflected light at the time of preliminary light emission is received by a photometric sensor provided in the imaging device, and at the time of preliminary light emission There is known a technique for determining the light emission amount of the flash device at the time of photographing based on the difference between the light amount of the reflected light and the light amount in a state where the flash device does not emit light. For example, in Patent Document 1, in order to reduce the time required for preliminary light emission, when the reflected light at the time of preliminary light emission is received by the photometric sensor, the pixel signal of each pixel constituting the photometric sensor is intermittent at predetermined pixel intervals. A method is disclosed in which the amount of light emitted by the flash device at the time of shooting is determined using image signals read out intermittently and intermittently read out.

JP 2006-50337 A

  However, in the prior art, when there is a point light source in the shooting screen, if even a slight blur occurs in the composition between the non-light emission and the preliminary light emission, the luminance from such a point light source is correctly acquired. As a result, there has been a problem that the amount of light emitted from the flash device at the time of photographing cannot be determined appropriately.

  The problem to be solved by the present invention is to provide a light emission amount control device and a light emission amount control method capable of appropriately determining the light emission amount of light emitting means such as a flash device even when the composition is blurred. It is.

  The present invention solves the above problems by the following means. In addition, although the code | symbol corresponding to drawing which shows embodiment of this invention is attached | subjected and demonstrated, this code | symbol is only for making an understanding of invention easy, and is not the meaning which limits invention.

[1] The light emission amount control device according to the present invention includes a light receiving means (136) having a plurality of light receiving elements for receiving a light beam and outputting a light reception signal, and a light emitting means (300 ) for emitting the light beam to an object. One of a first light receiving signal obtained by a first light receiving element of the plurality of light receiving elements in a state of not emitting light, and a second light receiving signal obtained by a second light receiving element different from the first light receiving element; Based on the third light receiving signal obtained by the first light receiving element in a state where the light emitting means emits the first light flux, the light emission amount of the second light flux different from the first light flux by the light emitting means is calculated. Control means (150) for determining, and when the difference between the first light receiving signal and the third light receiving signal is smaller than the difference between the second light receiving signal and the third light receiving signal, Before the first light reception signal A light emission amount of the second light flux is determined using a third light reception signal, and the control means determines that the difference between the first light reception signal and the third light reception signal is the second light reception signal and the third light reception signal. When the difference from the signal is larger, the light emission amount of the second light flux is determined using the second light reception signal and the third light reception signal .

  [2] In the invention related to the light emission amount control device, the control means (150) selects either the first light reception signal or the second light reception signal based on the third light reception signal. And

  [3] In the invention related to the light emission amount control device, the control means (150) is configured to output a difference between the output of the third light reception signal and the output of the first light reception signal and the output of the second light reception signal. And either one of the first light receiving signal and the second light receiving signal is selected based on the calculated difference.

[4] The light emission amount control device according to the present invention includes a light receiving unit having a plurality of light receiving elements that receive a light beam and output a light reception signal, and a light emitting unit that emits the light beam to a target in a state in which no light is emitted. Either the first light receiving signal obtained by the first light receiving element of the plurality of light receiving elements or the second light receiving signal obtained by the second light receiving element different from the first light receiving element, and the light emitting means is the first Control means for determining a light emission amount of the second light flux different from the first light flux by the light emitting means based on a third light receiving signal obtained by the first light receiving element in a state where the light flux is emitted; A blur detecting unit that detects a blur amount of the light receiving unit when the first light beam is emitted by the light emitting unit, and the control unit is configured to detect the blur amount detected by the blur detecting unit based on the blur amount detected by the blur detecting unit. First And selects one of the optical signal and the second light receiving signal.
[ 5 ] In the invention related to the light emission amount control device, the control means (150) includes the output of the light reception signal selected from the first light reception signal or the second light reception signal, and the third light reception signal. The light emission amount of the second light flux is determined based on the difference from the output.

[6] A light emission amount control device according to the present invention includes a control unit that performs preliminary light emission control and main light emission control of a light emitting unit, a first light receiving element, and a second light receiving element that is different from the first light receiving element, Before the light emitting section performs the preliminary light emission, the first light receiving element outputs a first light receiving signal, and the second light receiving element outputs a second light receiving signal, and the light emitting section When performing preliminary light emission, a light receiving unit that outputs a third light receiving signal from the first light receiving element, and a difference between the first light receiving signal and the third light receiving signal is the second light receiving signal and the third light receiving signal. Is smaller than the difference between the first light reception signal and the third light reception signal, the light emission amount of the main light emission is determined, and the difference between the first light reception signal and the third light reception signal is the second light reception signal. When the difference between the received light signal and the third received light signal is greater, the second received light signal Characterized by comprising a determining unit for determining the light emission amount of the main emission by using the third light receiving signal.
[7] A light emission amount control device according to the present invention includes a control unit that performs preliminary light emission control and main light emission control of a light emitting unit, a first light receiving element, and a second light receiving element that is different from the first light receiving element, Before the light emitting section performs the preliminary light emission, the first light receiving element outputs a first light receiving signal, and the second light receiving element outputs a second light receiving signal, and the light emitting section When performing preliminary light emission, a light receiving unit that outputs a third light receiving signal from the first light receiving element, one of the first light receiving signal and the second light receiving signal, and the third light receiving signal are used to perform the main light emission. A determination unit that determines a light emission amount, wherein the determination unit selects one of the first light reception signal and the second light reception signal using a blur amount of the apparatus when performing the preliminary light emission, A signal selected from the first light receiving signal and the second light receiving signal; and 3 and determines the light emission amount of the main emission by using the light receiving signal.
[8] A light emission amount control device according to the present invention includes a controller that performs preliminary light emission control and main light emission control, a first light receiving element, and a second light receiving element that is different from the first light receiving element. Before the light emitting unit performs the preliminary light emission, the first image signal corresponding to the output of the first light receiving element and not corresponding to the output of the second light receiving element, and the output of the second light receiving element. When the second image signal not corresponding to the output of the first light receiving element is output and the light emitting unit performs the preliminary light emission, the second image signal corresponds to the output of the first light receiving element and does not correspond to the output of the second light receiving element. A light receiving unit that outputs three image signals, and when the difference between the first image signal and the third image signal is smaller than the difference between the second image signal and the third image signal, A light emission amount of the main light emission is determined using the third image signal, and the first image signal is determined. When the difference between the image signal and the third image signal is larger than the difference between the second image signal and the third image signal, the main light emission is performed using the second image signal and the third image signal. And a determining unit that determines the amount of light emission.

[ 9 ] An imaging apparatus according to the present invention includes the light emission amount control apparatus according to the above invention.

[ 10 ] In the light emission amount control method according to the present invention, the light beam in the state of emitting the first light beam to the object and the light beam in the state of not emitting light are received by the plurality of light receiving elements and are not emitted. A first light-receiving signal obtained by a first light-receiving element of the plurality of light-receiving elements, a second light-receiving signal obtained by a second light-receiving element different from the first light-receiving element, and the target A third light receiving signal obtained by the first light receiving element in a state where one light beam is emitted is acquired, and based on one of the first light receiving signal and the second light receiving signal and the third light receiving signal A light emission amount control method for determining a light emission amount of a second light beam different from the first light beam, wherein a difference between the first light reception signal and the third light reception signal is different from the second light reception signal and the second light reception signal. 3 Less than the difference from the received light signal The first light receiving signal and the third light receiving signal are used to determine the amount of light emitted from the second light flux, and the difference between the first light receiving signal and the third light receiving signal is the second light receiving signal. And the third light reception signal, the light emission amount of the second light flux is determined using the second light reception signal and the third light reception signal.

[ 11 ] In the invention related to the light emission amount control method, one of the first light reception signal and the second light reception signal is selected based on the third light reception signal.

[ 12 ] In the invention related to the light emission amount control method, the difference between the output of the third light reception signal and each of the output of the first light reception signal and the output of the second light reception signal is calculated, Based on this, either the first light reception signal or the second light reception signal is selected.

[ 13 ] In the invention according to the light emission amount control method, based on a difference between an output of the selected light reception signal and the output of the third light reception signal among the first light reception signal or the second light reception signal, The light emission amount of the second light beam is determined.

  According to the present invention, it is possible to provide a light emission amount control device and a light emission amount control method that can appropriately determine the light emission amount of light emission means such as a flash device even when the composition is blurred.

FIG. 1 is a diagram illustrating a main configuration of a single-lens reflex digital camera 1 according to the present embodiment. FIG. 2 is a flowchart showing the operation of the camera 1 according to this embodiment. FIG. 3 is a view showing the photometric sensor 136 according to the present embodiment. FIG. 4A to FIG. 4C are diagrams showing output patterns of non-light emitting image signals according to the present embodiment. FIG. 5 is a diagram showing an example of a scene according to the present embodiment. FIG. 6 is a diagram illustrating the output of the image signal A during non-light emission in the scene example illustrated in FIG. FIG. 7 is a diagram illustrating the output of the non-light emitting image signal B in the scene example illustrated in FIG. FIG. 8 is a diagram showing the output of the non-light emitting image signal C in the example of the scene shown in FIG. FIG. 9 is a diagram illustrating the output of the image signal during preliminary light emission in the case where the composition blur does not occur in the scene example illustrated in FIG. FIG. 10 is a diagram illustrating the output of the image signal during preliminary light emission when composition blur occurs in the scene example illustrated in FIG. FIG. 11 is a diagram illustrating the difference between the output of the image signal during preliminary light emission and the output of the image signal A during non-light emission. FIG. 12 is a diagram for explaining the effect of the present embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing a main configuration of a single-lens reflex digital camera 1 according to the present embodiment, and a general configuration of a single-lens reflex digital camera system other than the configuration related to the light emission amount control device and the imaging device according to the invention described above. Some illustrations and explanations thereof are omitted.

  The single-lens reflex digital camera 1 (hereinafter simply referred to as the camera 1) of the present embodiment includes a camera body 100, a lens barrel 200, and a flash device 300. The lens barrel 200 and the flash device 300 are each mounted. The camera body 100 is detachably coupled via the unit.

  The lens barrel 200 includes a photographing optical system including lenses 210 and 220, a diaphragm device 230, and the like.

  The lens 220 is a focus lens, for example, and is provided so as to be movable along the optical axis L1, and its position is adjusted by a lens driving motor (not shown).

  The aperture device 230 is configured such that the aperture diameter around the optical axis L1 can be adjusted in order to limit the amount of light beam that passes through the imaging optical system and reaches the image sensor 110 and to adjust the amount of blur. .

  As shown in FIG. 1, the camera body 100 includes a quick return mirror 120 for guiding the light flux from the subject to the image sensor 110, the finder 134, and the photometric sensor 136.

  In FIG. 1, a state where the quick return mirror 120 is at the observation position of the subject is indicated by a solid line, and a state where the quick return mirror 120 is at the photographing position of the subject is indicated by a two-dot chain line. The quick return mirror 120 is inserted on the optical path of the optical axis L1 in a state where the subject is in the observation position of the subject, and rotates so as to be retracted from the optical path of the optical axis L1 in a state where the subject is in the photographing position.

  In a state where the quick return mirror 120 is at the observation position of the subject, the luminous flux (optical axis L1) from the subject is reflected by the quick return mirror 120 and guided to the finder 134 and the photometric sensor 136 (optical axes L2, L3). ). On the other hand, when the photographer presses the release button 140, the quick return mirror 120 is rotated to the photographing position, and the light flux (optical axis L1) from the subject is guided to the image sensor 110.

  The image sensor 110 is provided on the camera body 100 at a position on the optical axis L1 of the light beam from the subject and serving as a planned focal plane of the photographing optical system, and a shutter 111 is provided on the front surface thereof. The imaging element 110 is a two-dimensional array of a plurality of photoelectric conversion elements, and can be constituted by a two-dimensional CCD image sensor, a CMOS sensor, a CID, or the like. The electrical image signal photoelectrically converted by the image sensor 110 is transmitted to the camera control device 150, subjected to image processing by the camera control device 150, and stored in a memory (not shown). Note that the memory for storing the photographed image can be constituted by a built-in memory or a card-type memory.

  On the other hand, the subject light reflected by the quick return mirror 120 forms an image on a focusing screen 131 disposed on a surface optically equivalent to the image sensor 110 and is photographed by the photographer via the pentaprism 132 and the eyepiece 133. Observable. Accordingly, the subject and its background can be observed through the finder 134 in a state where the release is not performed.

  A photometric lens 135 and a photometric sensor 136 are provided in the vicinity of the eyepiece 133 to receive part of the subject light imaged on the focusing screen 131. The photometric sensor 136 is composed of a CMOS sensor or the like. The electrical image signal photoelectrically converted by the photometric sensor 136 is transmitted to the camera control device 150 and used to calculate the amount of flash light emitted by the flash device 300.

  The camera control device 150 is electrically connected to a lens control device (not shown) provided in the lens barrel 200, receives lens information, and supplies the lens control device such as the aperture diameter of the aperture and the driving amount of the lens 220. Send information. The camera control device 150 is electrically connected to a flash control device (not shown) provided in the flash device 300, and controls the entire camera 1 such as transmitting a light emission command.

  As the light emission command transmitted from the camera control device 150 to the flash control device, the flash light emission amount of the flash device 300 at the time of photographing the subject is calculated in addition to the light emission command at the time of photographing the subject by the image sensor 110. For example, a preliminary light emission command for performing preliminary light emission for the purpose. Further, the camera control device 150 calculates the flash light emission amount by the flash device 300 obtained by acquiring the electric image signal from the photometric sensor 136 as described above, and the calculated flash light emission amount together with the flash light emission command at the time of shooting. By transmitting to the flash device 300, the flash light emission amount of the flash device 300 during photographing of the subject is controlled.

  In the flash device 300, a flash control device (not shown) provided in the flash device 300 receives a light emission command transmitted from the camera control device 150, and performs flash light emission on the subject based on the light emission command. .

  Next, an operation example of the camera 1 according to this embodiment will be described. FIG. 2 is a flowchart showing the operation of the camera 1 according to this embodiment. The operation described below is started when the camera 1 is turned on.

  First, in step S1, when the power of the camera 1 is turned on, an image signal for photometry is acquired by the photometric sensor 136 in a state where the flash device 300 does not emit flash light. The acquired image signal is output to the camera control device 150. Here, a method of outputting an image signal acquired by the photometric sensor 136 in the present embodiment will be described. FIG. 3 is a diagram showing the photometric sensor 136. As shown in FIG. 3, the photometric sensor 136 is formed by arranging horizontal 20 × vertical 30 pixels. In the present embodiment, the horizontal coordinates of these pixels are i = 0-19, and the vertical coordinates are j = 0-29.

  In the present embodiment, the image signals have different output patterns as shown in FIGS. 4A to 4C, and the image signals corresponding to these patterns are transmitted to the camera control device 150. Output to. That is, in this embodiment, three types of image signals are output. In FIGS. 4A to 4C, the shaded pixels correspond to pixels for outputting an image signal. That is, in the pattern shown in FIG. 4A, pixels with j = 0, 3, 6, 9, 12, 15, 18, 18, 21, 24, 27 are pixels for outputting an image signal, and others No output is performed for the pixels in this row. An image signal having the pattern shown in FIG. 4A is referred to as “non-light emitting image signal A”. Similarly, in the pattern shown in FIG. 4B, pixels with j = 1, 4, 7, 10, 13, 16, 19, 22, 25, 28 are pixels for outputting an image signal. An image signal having this pattern is referred to as “non-light emitting image signal B”. Further, in the pattern shown in FIG. 4C, pixels with j = 2, 5, 8, 11, 14, 17, 20, 23, 26, 29 are pixels for outputting an image signal. An image signal composed of a pattern is referred to as “non-light emitting image signal C”.

  In this embodiment, the image signal acquired by the photometric sensor 136 is output to the camera control device 150 as three different non-light emitting image signals A to C.

  For example, in a scene as shown in FIG. 5 (a scene in which sunlight as a point light source exists behind the subject in the shooting screen), as shown in FIG. 6B does not include the image signal of the pixel in the part where sunlight as a point light source exists, so that as shown in FIG. The output due to the presence of sunlight is not included. FIG. 6B is a diagram showing the output of the non-light-emitting image signal A in the scene shown in FIG. 6A, where the relatively low luminance portions are indicated by dark dots, The relatively high luminance portions are indicated by thin dots (the same applies to FIGS. 7B, 8B, 9B, and 10B described later).

  On the other hand, in the scene as shown in FIG. 5, as shown in FIGS. 7A and 8A, the non-light-emitting image signal B and the non-light-emitting image signal C have sunlight as a point light source. 7 (B) and FIG. 8 (B), the output of the non-light emitting image signal B and the non-light emitting image signal C includes dots as shown in FIGS. The output resulting from the presence of sunlight as the light source is included.

  Next, in step S2, the camera control device 150 determines whether or not the release switch 140 has been depressed. If the release switch 140 has been depressed, the process proceeds to step S2. . On the other hand, when the release switch 140 is not depressed, it is determined whether or not the power of the camera 1 is turned off until the release switch 140 is depressed (step S3), and the above-described operation. Acquisition of image signals for photometry by the photometric sensor 136 and output of the acquired image signals (non-light emitting image signals A to C) to the camera control device 150 (step S1) are repeated. Note that if it is determined in step S3 that the power of the camera 1 has been turned off, this processing ends.

  In step S3, the camera control device 150 sends to the flash control device provided in the flash device 300 a preliminary light emission command for performing preliminary light emission for measuring the flash light emission amount of the flash device 300 when photographing the subject. Based on this, preliminary light emission is performed by the flash device 300. At this time, the photometric sensor 136 acquires an image signal for photometry during preliminary light emission, and the image signal acquired by the photometric sensor 136 is output to the camera control device 150. In the present embodiment, the image signal having the output pattern shown in FIG. 4A described above (that is, the image signal having the same output pattern as that of the above-described non-light emitting image signal A) is used as the image signal at the time of preliminary light emission. Image signal) is selected. That is, pixels with j = 0, 3, 6, 9, 12, 15, 18, 21, 24, 27 are pixels for outputting an image signal at the time of preliminary light emission, and pixels in other rows are Do not output.

  For example, in step S3, when the composition has not been changed and there is no composition blur as compared with the case in step S1, preliminary light emission is performed as shown in FIG. Since the time image signal does not include the image signal of the pixel in the part where the sunlight as the point light source exists, as shown in FIG. The output resulting from the presence of sunlight as a light source is not included. In FIG. 9B, since the preliminary flash is performed by the flash device 300, the subject portion is brighter than the background portion.

  On the other hand, in step S3, compared to the case in step S1, the composition is not changed, but when composition blurring occurs, as shown in FIG. Since the image signal includes an image signal of a pixel in a portion where sunlight as a point light source exists, as shown in FIG. Output due to the presence of sunlight.

  In step S5, of the non-light emitting image signals A to C acquired in step S1 by the camera control device 150, selection of the non-light emitting image signal used for determining the flash emission amount by the flash device 300 at the time of shooting. Is done. Hereinafter, a method for selecting an image signal will be described.

  In the following, the output of each pixel in the non-light emitting image signals A to C (output after A / D conversion) is Voy [i] [j] [k], and each pixel in the preliminary light emitting image signal is output. The output (output after A / D conversion) will be described as VoySB [i] [j]. Here, i = 0 to 19, j = 0 to 9, k = 0 to 2, and k = 0 represents the non-light emitting image signal A, and k = 1 represents the non-light emitting image. The signal B is represented. When k = 2, the non-light emitting image signal C is represented. The outputs Voy [i] [j] [k] and VoySB [i] [j] of each pixel take integer values from 0 to 1023.

First, the camera control device 150 calculates a difference (Sabun [k]) between the non-light emission image signals A to C and the preliminary light emission image signal according to the following equation (1).
Sabun [k] = ΣΣ ABS (VoySB [i] [j] −Voy [i] [j] [k] × Intpx / IntpxBack) (1)
In the above formula (1), ABS () is a function that returns the absolute value of the argument, Intpx is the accumulation time of the photometric sensor 306 when the image signal at the time of preliminary light emission is acquired, and IntpxBack is a non-light emission This is the accumulation time of the photometric sensor 306 when the hour image signals A to C are acquired. In the above formula (1), “ΣΣ” means that addition is repeatedly performed on i, j (i = 0 to 19, j = 0 to 9).

  In this embodiment, the difference (Sabun [k]) according to the above equation (1) is calculated for each of k = 0 to 2 (that is, the non-light emitting image signals A to C), Among these, the one with the smallest difference (Sabun [k]) is selected as a non-light emitting image signal used to determine the flash emission amount. That is, for example, when the difference (Sabun [0]) when k = 0 is the smallest, the non-light emitting image signal A is selected as the non-light emitting image signal used to determine the flash emission amount. . Similarly, when the difference (Sabun [1]) when k = 1 is the smallest, the image signal B when not emitting light is the smallest when the difference (Sabun [2]) when k = 2 is smallest. The non-light-emission image signal C is selected as a non-light-emission image signal used for determining the flash emission amount.

  For example, as shown in FIG. 9A, in the case where there is no composition blur at step S3, as shown in FIG. The output due to the presence of is not included. Therefore, similarly, the non-light-emitting image signal A that does not include the output due to the presence of sunlight as a point light source is selected as the one having the smallest output difference (Sabun [k]). It becomes. That is, k = 0 is selected. FIG. 11 is a diagram showing a difference between the output of the image signal during preliminary light emission and the output of the image signal A during non-light emission. In FIG. 11, a portion having a small difference is indicated by a dark dot, while a portion having a large difference is indicated by a thin dot (the same applies to FIG. 12 described later).

  On the other hand, as shown in FIG. 10A, when composition blur occurs in step S3, as shown in FIG. 10B, a point light source is used to output the preliminary light emission image signal. As a result, the output resulting from the presence of sunlight is included. Therefore, similarly, the non-light-emitting image signal B including the output due to the presence of sunlight as a point light source is selected as the one having the smallest output difference (Sabun [k]). Become. That is, k = 1 is selected.

  In step S6, the camera control device 150 calculates the flash emission amount of the flash device 300 during shooting using the non-light emission image signal and the preliminary light emission image signal selected in step S5. Hereinafter, a method of calculating the flash emission amount of the flash device 300 at the time of shooting will be described.

First, the camera control device 150 calculates the average reflection amount RM of the entire screen in the photometric image measured by the photometric sensor 306 according to the following formula (2). In the following equation (2), as Voy [i] [j] [k], the output of the non-light emitting image signal selected in step S5 described above is used. That is, when the non-light emitting image signal A is selected, Voy [i] [j] [0] is used, and when the non-light emitting image signals B and C are selected, Voy [i]. [J] [1] and Voy [i] [j] [2] are used, respectively.
RM = (ΣΣ (VoySB [i] [j] −Voy [i] [j] [k] × Intpx / IntpxBack) / (i × j)) (2)
In the above formula (2), Intpx is the accumulation time of the photometric sensor 306 when the pre-light emission image signal is acquired, and IntpxBack is the photometric sensor 306 when the non-light emission image signals A to C are acquired. Is the accumulation time. In the above formula (1), “ΣΣ” means that addition is repeatedly performed on i, j (i = 0 to 19, j = 0 to 9).

  In the above equation (2), the output of the non-light emission image signal selected in step S5 is subtracted from the output of the preliminary light emission image signal to extract the reflected light component based on the preliminary light emission. Is obtained to obtain an average reflection amount RM of the entire screen.

Next, the camera control device 150 calculates a light emission amount guide number GN according to the following equation (3). The light emission amount guide number GN corresponds to the flash light emission amount of the flash device 300.
GN = Power√2 (−Log ₂ (RM) + GvMon + GNConst) (3)
However, in the above formula (3), Power√2 () is a function that returns the power of the argument of √2, and Log ₂ () is a function that returns the logarithmic value of the argument with 2 as the base. GNConst is a constant term for using the light emission amount as a reference value, and GvMon is calculated by the following equation (4).
GvMon = Log _√2 (GnMon) (4)
In the above equation (4), Log _√2 is a function that takes a logarithmic value of an argument with √2 as the base, and GnMon is a light emission amount guide number at the time of preliminary light emission in step S3.

  Then, the calculated light emission amount guide number GN (flash emission amount) is transmitted by the camera control device 150 to the flash control device provided in the flash device 300 according to the above equation (3).

  Next, in step S7, a subject image is taken. Specifically, first, the camera control device 150 performs a jumping upward operation (moving to the two-dot chain line portion in FIG. 1) of the quick return mirror 120 and an opening operation of the shutter 111. The camera control device 150 transmits a shooting light emission command to the flash control device provided in the flash device 300, and the flash device 300 sets the light emission amount guide number GN (flash light emission amount) calculated in step S6. Based on this, flash emission is performed, and in synchronism with this, the image pickup device 110 captures a subject image. Thereafter, the camera control device 150 performs an operation for returning the quick return mirror 120 to its original position and an operation for closing the shutter 111.

  In step S8, it is determined whether or not the camera 1 is turned off. If it is determined that the power of the camera 1 has been turned off, this process is terminated. On the other hand, if it is determined that the power of the camera 1 is not turned off, the process returns to step S1 and the above-described processing is repeatedly executed.

  The camera 1 according to the present embodiment operates as described above.

  In the present embodiment, as a preliminary light emission image signal output from the photometry sensor 136 at the time of preliminary light emission, as shown in FIG. 4A, a specific part of pixels are pixels for outputting an image signal, and 4A to 4C, the difference in output from the non-light emitting image signals A to C shown in FIG. 4C is calculated, the one having the smallest output difference is selected, and the selected non-light emitting image signal and The flash emission amount of the flash device 300 is calculated based on the preliminary emission image signal. Therefore, according to the present embodiment, the flash device 300 is configured such that a specific partial pixel is a pixel for outputting an image signal, thereby increasing the output speed of the image signal during the preliminary light emission during the preliminary light emission. It is possible to appropriately determine the amount of flash emission.

  In addition, according to the present embodiment, the difference between the output of the preliminary light emission image signal and the non-light emission image signals A to C is calculated, and based on this, the flash light emission amount of the flash device 300 is calculated. Therefore, even when a composition blur occurs as shown in FIG. 10A, the flash emission amount can be appropriately determined. In particular, in the case shown in FIG. 10A, if the difference between the output of the non-light emitting image signal A having the same pattern and the output of the preliminary light emitting image signal shown in FIG. As shown in FIG. 12, there is a problem that a large difference occurs in the pixel of the portion where the sunlight that is the point light source exists, and as a result, there is a problem that the flash emission amount cannot be appropriately determined. On the other hand, in this embodiment, such a problem is effectively solved by having the said structure.

  The embodiment described above is described for facilitating the understanding of the invention, and is not described for limiting the invention. Therefore, each element disclosed in the above embodiment includes all design changes and equivalents belonging to the technical scope of the above invention.

  For example, in the above-described embodiment, the pixel pattern for image signal output of the photometric sensor 136 is three types of patterns, but the number is not limited and can be set as appropriate. In the above-described embodiment, the pixel pattern for outputting the image signal of the photometric sensor 136 is an intermittent pattern along the vertical direction, but may be a pattern that is intermittent along the horizontal direction. .

  In the above-described embodiment, the configuration for performing the measurement for determining the flash emission amount of the flash device 300 by the photometric sensor 136 is illustrated, but the image sensor 110 is used instead of the photometric sensor 136. It is good also as a structure.

  Furthermore, in the above-described embodiment, the camera 1 has an angular velocity sensor, and when the non-light emitting image signal used for determining the flash emission amount by the flash device 300 at the time of shooting is selected by the angular velocity sensor, A configuration may be adopted in which camera shake is detected and the non-light emitting image signal used to determine the flash emission amount is determined based on the blur amount.

DESCRIPTION OF SYMBOLS 1 ... Single-lens reflex digital camera 100 ... Camera body 110 ... Image pick-up element 136 ... Photometric sensor 140 ... Release switch 150 ... Camera control apparatus 200 ... Lens barrel 300 ... Flash apparatus

Claims (13)

A light receiving means having a plurality of light receiving elements for receiving a light beam and outputting a light reception signal;
A first light receiving signal obtained by the first light receiving element among the plurality of light receiving elements in a state where the light emitting means for emitting a light beam to the target is not emitting light, and a second light receiving element different from the first light receiving element And the third light receiving signal obtained by the first light receiving element in a state in which the light emitting means emits the first light flux, and the first light flux by the light emitting means. And a control means for determining the light emission amount of the second light flux different from
When the difference between the first light receiving signal and the third light receiving signal is smaller than the difference between the second light receiving signal and the third light receiving signal, the control means is configured to output the first light receiving signal and the third light receiving signal. And determining the light emission amount of the second light flux using
When the difference between the first light receiving signal and the third light receiving signal is larger than the difference between the second light receiving signal and the third light receiving signal, the second light receiving signal and the third light receiving signal are used to A light emission amount control device that determines the light emission amount of the second light flux. The light emission amount control device according to claim 1,
The light emission amount control device, wherein the control means selects either the first light reception signal or the second light reception signal based on the third light reception signal. The light emission amount control device according to claim 1,
The control means calculates a difference between the output of the third received light signal and each of the output of the first received light signal and the output of the second received light signal, and based on the calculated difference, the first received light signal And the second light receiving signal are selected. A light receiving means having a plurality of light receiving elements for receiving a light beam and outputting a light reception signal;
A first light receiving signal obtained by the first light receiving element among the plurality of light receiving elements in a state where the light emitting means for emitting a light beam to the target is not emitting light, and a second light receiving element different from the first light receiving element And the third light receiving signal obtained by the first light receiving element in a state in which the light emitting means emits the first light flux, and the first light flux by the light emitting means. Control means for determining the light emission amount of the second light flux different from
A blur detection unit that detects a blur amount of the light receiving unit when the first light flux is emitted by the light emitting unit;
The light emission amount control device, wherein the control means selects one of the first light reception signal and the second light reception signal based on a shake amount detected by the shake detection means. In the luminescence amount control device according to any one of claims 1 to 4,
The control means is configured to emit light of the second light flux based on a difference between the output of the selected light reception signal and the output of the third light reception signal among the first light reception signal or the second light reception signal. A light emission amount control device, characterized in that: A control unit for controlling preliminary light emission and main light emission of the light emitting unit;
A first light receiving element and a second light receiving element that is different from the first light receiving element, and before the light emitting unit performs the preliminary light emission, outputs a first light receiving signal from the first light receiving element; A second light receiving signal is output from the second light receiving element;
A light receiving unit that outputs a third light receiving signal from the first light receiving element when the light emitting unit performs the preliminary light emission;
When the difference between the first light receiving signal and the third light receiving signal is smaller than the difference between the second light receiving signal and the third light receiving signal, the first light receiving signal and the third light receiving signal are used to Determine the amount of main flash
When the difference between the first light receiving signal and the third light receiving signal is larger than the difference between the second light receiving signal and the third light receiving signal, the second light receiving signal and the third light receiving signal are used to A light emission amount control device comprising: a determination unit that determines a light emission amount of main light emission. A control unit for controlling preliminary light emission and main light emission of the light emitting unit;
A first light receiving element and a second light receiving element that is different from the first light receiving element, and before the light emitting unit performs the preliminary light emission, outputs a first light receiving signal from the first light receiving element; A second light receiving signal is output from the second light receiving element;
A light receiving unit that outputs a third light receiving signal from the first light receiving element when the light emitting unit performs the preliminary light emission;
A determination unit that determines a light emission amount of the main light emission using any one of the first light reception signal and the second light reception signal and the third light reception signal;
The determination unit selects one of the first light reception signal and the second light reception signal using a blur amount of the apparatus when performing the preliminary light emission, and determines the first light reception signal and the second light reception signal. A light emission amount control device that determines the light emission amount of the main light emission using a selected signal and the third light reception signal. A control unit for controlling preliminary light emission and main light emission;
A first light receiving element and a second light receiving element different from the first light receiving element, wherein the second light receiving element corresponds to an output of the first light receiving element before the light emitting unit performs the preliminary light emission. A first image signal that does not correspond to the output of the second light receiving element, and a second image signal that corresponds to the output of the second light receiving element and does not correspond to the output of the first light receiving element,
A light-receiving unit that outputs a third image signal that corresponds to the output of the first light-receiving element and does not correspond to the output of the second light-receiving element when the light-emitting unit performs the preliminary light emission;
When the difference between the first image signal and the third image signal is smaller than the difference between the second image signal and the third image signal, the first image signal and the third image signal are used to Determine the amount of main flash
When the difference between the first image signal and the third image signal is larger than the difference between the second image signal and the third image signal, the second image signal and the third image signal are used to A light emission amount control device comprising: a determination unit that determines a light emission amount of main light emission. Imaging apparatus characterized by comprising a light emission amount control device according to any one of claims 1 to 8. The light beam in a state where the first light beam is emitted to the object and a state where the light beam is not emitted is received by a plurality of light receiving elements,
A first light receiving signal obtained by a first light receiving element of the plurality of light receiving elements in a state where no light is emitted, a second light receiving signal obtained by a second light receiving element different from the first light receiving element, and the target On the other hand, a third light receiving signal obtained by the first light receiving element in a state where the first light flux is emitted,
A light emission amount control method for determining a light emission amount of a second light beam different from the first light beam based on either the first light reception signal or the second light reception signal and the third light reception signal. ,
When the difference between the first light receiving signal and the third light receiving signal is smaller than the difference between the second light receiving signal and the third light receiving signal, the first light receiving signal and the third light receiving signal are used to Determine the amount of light emitted by the second luminous flux;
When the difference between the first light receiving signal and the third light receiving signal is larger than the difference between the second light receiving signal and the third light receiving signal, the second light receiving signal and the third light receiving signal are used to A light emission amount control method, wherein the light emission amount of the second light beam is determined. The light emission amount control method according to claim 10 ,
A light emission amount control method, wherein either the first light reception signal or the second light reception signal is selected based on the third light reception signal. The light emission amount control method according to claim 10 ,
A difference between the output of the third light reception signal and the output of the first light reception signal and the output of the second light reception signal is calculated, and the first light reception signal and the second light reception are calculated based on the calculated difference. A light emission amount control method, wherein one of the signals is selected. The light emission amount control method according to any one of claims 10 to 12 ,
Determining the light emission amount of the second light flux based on the difference between the output of the selected light reception signal and the output of the third light reception signal of the first light reception signal or the second light reception signal; A feature of the light emission amount control method.

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