JP2008170875A - Camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an image that a photographer intends even in situation that it is difficult to emit strobe light with correct color temperature in strobe photography. <P>SOLUTION: In a camera which is equipped with a strobe light source whose strobe light is adjustable in color temperature and takes pictures successively at predetermined time intervals in response to single-time shutter release operation, a system controller 52 reads the ratio of light emission quantities of R, G, B out of a memory 25 according to previously input color temperature information each time a picture is taken successively, and controls operational amplifiers 46, 48, 50 to obtain the read ratio of light emission quantities of R, G, B, thereby emitting the strobe light with a different color temperature each time the picture is taken successively. Consequently, a picture is taken through strobe light emission with a color temperature that the photographer has intended. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a camera, and more particularly, to a camera including a strobe device that can change the emission color of strobe light.

  Auto bracketing that automatically captures multiple photos continuously by changing the exposure value in steps with a single release operation for the camera's determined exposure values, ie shutter speed and aperture value. Cameras with a shooting function are widely known.

  Japanese Patent Application Laid-Open No. 2004-228561 describes a technique that can perform auto bracketing photography quickly and accurately even when performing auto bracketing photography using a strobe device.

  Some cameras such as a digital still camera have a white balance bracketing shooting function in which a bracketing shooting change parameter is set to white balance instead of an exposure value.

  Patent Document 2 describes a technology of a white balance bracketing shooting function that can automatically take a plurality of photos continuously by changing the white balance stepwise by a single release operation. ing.

  A conventional camera strobe device uses a xenon tube as a light source. For example, when strobe photography is performed in order to correct the backlight of sunlight in the morning or evening, the xenon tube has a spectral characteristic close to that of daylight, which may result in a photograph with an unnatural color.

In Patent Document 3, by using R, G, and B light emitting elements, the color temperature of the emitted color can be changed manually or automatically. For example, in the case of performing backlight correction of sunlight in the morning or evening Describes a technique capable of performing backlight correction in accordance with the color temperature of sunlight and eliminating unnaturalness due to the color temperature of the strobe light during flash photography.
Japanese Patent Laid-Open No. 5-196985 JP 2001-333432 A JP 2002-116481 A

  However, although the invention described in Patent Document 1 can obtain a properly exposed image using a strobe device, the color temperature of the strobe light source is constant, so that, for example, in the morning or evening sunlight When the backlight correction is performed, an unnatural color photograph may be obtained.

  In addition, the invention described in Patent Document 2 uses a white balance because the color temperature of the strobe light source is different from the color temperature of sunlight when a strobe is used to correct the backlight of sunlight in the morning or evening, for example. In bracketing photography, it is difficult to photograph both the subject irradiated with the strobe light source and the background irradiated with sunlight so as to achieve a good white balance.

  In the invention described in Patent Document 3, if there is an error in the measurement of the color temperature of the object scene, the color temperature of the strobe light set based on the measurement result cannot match the color temperature of the object scene. There is a problem.

  The present invention has been made in view of such circumstances. Even if there is an error in the measurement or setting of the color temperature of the object scene, the flash photography is performed with the strobe light having the same color temperature as the color temperature of the object scene. It is an object to provide a camera that can guarantee the above.

  In order to achieve the above object, the invention according to claim 1 is capable of adjusting the color temperature of the emitted strobe light in a camera that continuously shoots at a predetermined time interval in conjunction with a single shutter release operation. A strobe light source, light emission control means for emitting strobe light from the strobe light source in synchronization with each continuous photographing, and strobe light emitted from the strobe light source for each continuous photographing Color temperature adjusting means for adjusting the color temperature of the strobe light so that the color temperature is different within a predetermined color temperature variable range set in advance. It is characterized by having prepared.

  That is, it is possible to perform shooting with strobe light emission at a color temperature intended by the photographer by continuously shooting with the strobe light emission at different color temperatures.

  The camera according to claim 1, further comprising color temperature detection means for detecting a color temperature of an object scene, wherein the color temperature adjustment means is a color temperature detected by the color temperature detection means. The color temperature of the strobe light is adjusted so as to be different from each other within the set predetermined color temperature variable range.

  As a result, the center of the color temperature of the strobe light that emits light continuously can be set as the color temperature of the object scene.

  The camera according to claim 1, further comprising color temperature setting means for manually setting a color temperature including a light source type, wherein the color temperature adjusting means is set by the color temperature setting means. The color temperature of the strobe light is adjusted so that the color temperatures are different from each other within the set predetermined color temperature variable range with the color temperature as a center.

  As a result, the center of the color temperature of the strobe light that emits light continuously can be set to the manually set color temperature.

  According to a fourth aspect of the present invention, the camera according to the first aspect further includes a scene selection unit that selects a photographic scene, and the color temperature adjusting unit is configured to perform the predetermined process according to the photographic scene selected by the scene selection unit. The color temperature of the strobe light is adjusted so as to have different color temperatures within a variable color temperature range.

  Thereby, the center of the color temperature of the strobe light that emits light continuously can be set to the color temperature according to the shooting scene.

  According to a fifth aspect of the present invention, in the camera according to the first to fourth aspects, the strobe light source is composed of light emitting diodes of three colors of R, G, and B.

  According to a sixth aspect of the present invention, in the camera according to the fifth aspect, the color temperature adjusting unit adjusts the color temperature by controlling a ratio of light emission amounts of R, G, and B of the light emitting diodes of the three colors. It is characterized by that.

  As described in claim 7, in the camera according to claim 6, light emission of R, G, B of the three color light emitting diodes for emitting strobe light corresponding to each color temperature for each color temperature of a predetermined interval Storage means for storing the ratio of the amounts, and the color temperature adjustment means reads the ratio of the corresponding R, G, B emission amounts from the storage unit according to the color temperature to be emitted, and the read R, The light emission amounts of the light emitting diodes of the three colors are controlled so as to have a ratio of the light emission amounts of G and B.

  According to a eighth aspect of the present invention, in the camera according to the seventh aspect, the storage means stores the ratio of the light emission amounts of R, G, and B at different predetermined intervals according to the color temperature. It is characterized by.

  Thereby, the memory can be used efficiently.

  According to the present invention, even if it is difficult to stroboscope at the correct color temperature, the color intended by the photographer can be obtained by color bracketing shoot in which the stroboscope is continuously fired at different color temperatures. You can shoot with flashing light at temperature.

  Hereinafter, preferred embodiments of a camera according to the present invention will be described with reference to the accompanying drawings.

<First Embodiment>
FIG. 1 is a top view of an electronic camera capable of color bracketing photography according to the present invention.

  As shown in the figure, the mode dial 101 can be set to any one of the manual shooting mode, auto shooting mode, portrait mode, and the like by rotating. Further, a shutter release button 102 having a switch S1 that is turned on when half-pressed and a switch S2 that is turned on when fully pressed is provided at the front of the mode dial 101.

  FIG. 2 is a rear perspective view of an electronic camera capable of color bracketing photography according to the present invention.

  As shown in FIG. 2, a liquid crystal finder 103, a menu button 104, a cross button 105, and a liquid crystal monitor 152 are provided on the back of the electronic camera 100.

  FIG. 3 is a front perspective view of an electronic camera capable of color bracketing photography according to the present invention.

  A photographing lens 110 and a strobe device 146 are provided on the front surface of the electronic camera 100 as shown in FIG.

  FIG. 4 is a block diagram showing an internal configuration of the electronic camera 100 shown in FIG.

  In the figure, a subject image formed on a light receiving surface of a solid-state image sensor (CCD) 114 via a photographing lens 110 and a diaphragm 112 is converted into signal charges of an amount corresponding to the amount of incident light by each sensor. . The signal charges accumulated in this way are read out to the shift register by a read gate pulse applied from the CCD drive circuit 116, and sequentially read out as a voltage signal corresponding to the signal charge by a register transfer pulse. The CCD 114 has a so-called electronic shutter function that can sweep out the accumulated signal charge by a shutter gate pulse, thereby controlling the charge accumulation time (shutter speed).

  The voltage signal sequentially read from the CCD 114 is applied to a correlated double sampling circuit (CDS circuit) 118, where the R, G, and B signals for each pixel are sampled and held and applied to the A / D converter 120. It is done. The A / D converter 120 converts the R, G, and B signals sequentially added from the CDS circuit 118 into digital R, G, and B signals and outputs them. The CCD drive circuit 116, the CDS circuit 118, and the A / D converter 120 are driven in synchronism with a timing signal applied from the timing generation circuit 122.

  The R, G, B signals output from the A / D converter 120 are temporarily stored in the memory 124, and then the R, G, B signals stored in the memory 124 are added to the digital signal processing circuit 126. . The digital signal processing circuit 126 includes a synchronization circuit 128, a white balance adjustment circuit 130, a gamma correction circuit 132, a YC signal generation circuit 134, a memory 136, and the like.

  The synchronization circuit 128 converts the dot-sequential R, G, and B signals read from the memory 124 into a simultaneous expression, and outputs the R, G, and B signals to the white balance adjustment circuit 130 at the same time. The white balance adjustment circuit 130 includes multipliers 130R, 130G, and 130B for increasing and decreasing the digital values of the R, G, and B signals. The R, G, and B signals are respectively multiplied by the multipliers 130R, 130G, and 130B. Added to 130B. A white balance correction value (gain value) for white balance control is added from the central processing unit (CPU) 138 to other inputs of the multipliers 130R, 130G, and 130B. The multipliers 130R, 130G, and 130B Two inputs are respectively multiplied, and R ′, G ′, and B ′ signals that have been subjected to white balance adjustment by this multiplication are output to the gamma correction circuit 132. The details of the white balance correction value applied from the CPU 138 to the white balance adjustment circuit 130 will be described later.

  The gamma correction circuit 132 changes the input / output characteristics so that the white balance adjusted R ′, G ′, and B ′ signals have desired gamma characteristics, and outputs them to the YC signal generation circuit 134. The YC signal creation circuit 134 creates a luminance signal Y and chroma signals Cr and Cb from the gamma-corrected R, G, and B signals. These luminance signal Y and chroma signals Cr and Cb (YC signal) are stored in the memory 136 in the same memory space as the memory 124.

  Here, by reading the YC signal in the memory 136 and outputting it to the liquid crystal monitor 152, a through image, a captured still image, etc. can be displayed on the liquid crystal monitor 152.

  The YC signal after photographing is compressed into a predetermined format by the compression / decompression circuit 154 and then recorded on a recording medium such as a memory card by the recording unit 156. Further, in the reproduction mode, image data recorded on a memory card or the like is decompressed by the compression / decompression circuit 154 and then output to the liquid crystal monitor 152 so that the reproduced image is displayed on the liquid crystal monitor 152. .

  The CPU 138 performs overall control of each circuit based on input from the camera operation unit 140 including the mode dial 101, the shutter release button 102, the menu button 104, the cross button 105, and the like shown in FIG. Controls such as control and white balance. This autofocus control is, for example, contrast AF that moves the photographing lens 110 so that the high-frequency component of the G signal is maximized, and the drive unit so that the high-frequency component of the G signal is maximized when the shutter release button 102 is half-pressed. The photographing lens 110 is moved to the in-focus position via 142.

  In the automatic exposure control, R, G, and B signals are taken, subject luminance (shooting EV value) is obtained based on an integrated value obtained by integrating these R, G, and B signals, and shooting is performed based on the taken EV value. Determine the aperture value and shutter speed. Then, when the shutter release button 102 is fully pressed, the aperture 112 is driven via the aperture drive unit 144 so that the determined aperture value is obtained, and the electronic shutter is used to reduce the charge accumulation time so that the determined shutter speed is obtained. The image data for one frame is controlled, and after necessary signal processing, it is recorded on the recording medium.

  Next, a white balance correction method will be described.

  Although white balance correction is performed in the auto shooting mode, when manual white balance correction is performed, the manual shooting mode is set with the mode dial 101 and the menu button 104 is further operated, as shown in FIG. A menu for white balance setting is displayed on the liquid crystal monitor 152. Here, the cursor is moved up and down by the cross button 105, and an item for white balance correction (M, an icon indicating a light source type, AUTO) is selected.

  Here, a method for measuring the color temperature (light source type) of the object field measured when the auto shooting mode or the white balance is set to “AUTO” will be described.

  The R, G, and B signals are averaged for each divided area for dividing each screen into a plurality of areas (8 × 8) from the R, G, and B signals temporarily stored in the memory 124 shown in FIG. Find the integrated value. The average integrated value of the R, G, and B signals for each of these divided areas is calculated by the integrating circuit 148 and added to the CPU 138. Multipliers 150R, 150G, and 150B are provided between the integration circuit 148 and the CPU 138, and an adjustment gain value for adjusting variation of the devices is added to the multipliers 150R, 150G, and 150B. ing.

  The CPU 138 determines the type of light source such as daylight (clear), shade-cloudy, fluorescent lamp, tungsten bulb, etc., based on the average integrated value of the R, G, B signals for each of the divided areas. This light source type is determined by determining the ratio R / G, B / G of the average integrated values for each color of the R, G, B signals for each divided area, and then the horizontal axis is R / G and the vertical axis is B. A detection frame indicating a color distribution range corresponding to each light source type is set on the graph of / G. Then, the number of areas entering the detection frame is obtained based on the ratios R / G and B / G for each area thus obtained, and the light source type is determined based on the luminance level of the subject and the number of areas entering the detection frame. (See JP 2000-224608). The method for automatically obtaining the light source type (color temperature of the object scene) is not limited to this embodiment, and the color temperature is determined based on the ratio of the luminance information of the R, G, and B signals obtained from the CCD 114. It may be calculated.

  When the CPU 138 obtains the light source type (the color temperature of the object scene) as described above, the CPU 138 determines a white balance correction value suitable for the light source type, and a multiplier for the determined white balance correction value (gain value). Output to 130R, 130G, and 130B. Thereby, the white balance adjusted R ′, G ′, B ′ signals are output from the multipliers 130 R, 130 G, 130 B to the gamma correction circuit 132.

  Here, when the white balance is set to “M”, the stored color temperature is read based on the operation for storing the color temperature in advance, the white balance correction value corresponding to the color temperature is determined, and the white balance is similarly set. Make corrections.

  When the white balance is set to an icon indicating the light source type, a white balance correction value suitable for the selected light source type is determined and white balance correction is performed.

In this embodiment, the white balance processing is performed in the digital signal processing circuit 126. However, the white balance processing may be performed in an analog signal processing circuit including a CDS circuit 118 and a gain control amplifier (not shown). . The white balance processing is performed by changing the ratio of R / G and B / G by independent gain processing for each of R, G, and B. However, independent addition / subtraction processing is performed for each of the color difference signals C _r and C _b. Thus, there is also a method of performing by adding or subtracting a value in the color difference signals C _r and C _b .

  Next, a method for controlling the strobe device 146 according to the present invention will be described.

  FIG. 5 is a block diagram showing details of the strobe device 146 built in or externally attached to the electronic camera 100.

  As shown in FIG. 5, the strobe device 146 includes a light receiving sensor 34 for strobe dimming, an LED group 38, a battery 40, a voltage up-converter 42, a large-capacitance capacitor 44, operational amplifiers 46, 48, 50, a system controller 52, A dimming circuit 54 and a temperature sensor 56 are provided.

  The system controller 52 performs overall control of the strobe device 146, and a light emission signal synchronized with the shutter release, strobe light emission amount information and strobe color temperature information are input from the CPU 138 through serial communication. The system controller 52 controls the voltage up-converter 42 to boost the voltage (for example, 6V) of the battery 40 to about 10V and charge the capacitor 44 with the boosted voltage. The capacitor 44 is charged for a long time of about 2 to 5 seconds, for example, and can continuously supply current to the LED group 38 for 1/60 seconds (about 16 milliseconds) or longer.

  The electrical energy stored in the capacitor 44 is supplied to the R, G, and B LEDs 38R, 38G, and 38B via the operational amplifiers 46, 48, and 50. The system controller 52 uses the strobe emission information from the CPU 138 and the strobe light. Based on the color temperature information, the operational amplifiers 46, 48, and 50 are controlled to control the light emission time and light emission amount of the R, G, and B LEDs 38R, 38G, and 38B.

  Since the light amount of the LED varies depending on the ambient temperature, a temperature sensor 56 for detecting the ambient temperature of the LED group 38 is provided. The system controller 52 detects the ambient temperature of the LED group 38 detected by the temperature sensor 56. Based on the above, current control to the LED group 38 is performed so that a required light emission amount can be obtained regardless of the ambient temperature.

  Next, the operation of the system controller 52 will be described with reference to the timing chart shown in FIG.

  The system controller 52 operates the voltage up-converter 42 in advance at the power-on timing of a camera (not shown) to charge the capacitor 44 in advance.

  Thereafter, when the shutter release button 102 is half-pressed, the camera enters a standby state (FIG. 6A), and information for determining the flash emission amount such as a guide number is captured.

  Here, the CPU 138 reads the color temperature stored in advance when the white balance shooting item is “M”, and the R obtained from the CCD 114 when the auto shooting mode or the white balance shooting item is “AUTO”. The light source type (the color temperature of the object scene) is automatically obtained based on the G, B signals, and the color temperature for white balance correction is set.

  The color temperature for white balance correction is outputted from the CPU 138, and the system controller 52 takes in the color temperature outputted from the CPU 138 (FIG. 6B).

  The system controller 52 determines the flash emission amount based on the acquired information, outputs a reference value for adjusting the flash emission amount to obtain the flash emission amount to the dimming circuit 54, and displays the color of the object scene. Based on the temperature, the light emission amount ratio of the R, G, B LEDs 38R, 38G, 38B is determined so that light of the same color temperature is emitted, and the R, G, B light emission levels corresponding to this ratio are set. (FIG. 6C).

  Next, when the shutter release button 102 is fully pressed and the shutter is opened, the system controller 52 inputs a light emission signal synchronized with the shutter opening, and outputs control signals indicating the set R, G, and B light emission levels, respectively. Output to 46, 48, 50 positive inputs. On the other hand, signals corresponding to the current values flowing through the LEDs 38R, 38G, and 38B are added to the negative inputs of the operational amplifiers 46, 48, and 50. The operational amplifiers 46, 48, and 50 have the R, G, and B set as described above. Control is performed so that a constant current corresponding to the light emission level flows to each of the LEDs 38R, 38G, and 38B.

  As a result, strobe light having the same color temperature as the color temperature of the object scene is emitted from the LED group 38 as a whole (FIG. 6D).

  When strobe light is emitted from the LED group 38, the light control circuit 54 detects the light emission amount via the light receiving sensor 34 for strobe light control. When the detected light emission amount matches the reference value for adjusting the light emission amount, a light emission stop signal is output to the system controller 52 in order to stop the light emission. When the system controller 52 receives a light emission stop signal from the dimming circuit 54, the system controller 52 outputs a control signal for stopping the light emission of the LED group 38 to the operational amplifiers 46, 48 and 50. Thereby, the electric current which flows into LED group 38 is interrupted | blocked, and light emission of LED group 38 stops.

  Next, a method for controlling color bracketing photography according to the present invention will be described with reference to FIGS.

  8 is a flowchart showing the operation of the camera at the time of color bracketing shooting, FIG. 9 is a diagram showing the display inside the viewfinder 103 at the time of color bracketing shooting, and FIG. 10 is the system controller at the time of color bracketing shooting. 52 is a timing chart showing the operation of 52.

  First, a case where the color bracketing color temperature selection is set to automatic selection “AUTO” will be described.

  When the photographer turns on the power of the camera, the system controller 52 operates the voltage up-converter 42 in advance to charge the capacitor 44 (FIG. 8 (S1)).

  Next, using the mode dial 101, the menu button 104, and the cross button 105 of the camera 100, mode settings for color bracketing shooting such as shooting mode selection and strobe shooting selection are performed (S2 in FIG. 8).

  When the color bracketing shooting is selected, the bracketing width is selected (step S3 in FIG. 8) for the next plus or minus number of steps of bracketing.

  Although steps will be described later, it is assumed here that plus or minus one step is selected.

  Next, the number of bracketing sheets to be selected is selected (FIG. 8 (S4)). Here, it is assumed that three are selected.

  When the selection of the bracketing width and the selection of the number of bracketing are completed, the color temperature selection setting is performed (S5 in FIG. 8).

  There are two types of color temperature selection: automatic selection “AUTO” and manual selection “M”. Here, the color temperature selection is set to automatic selection “AUTO”.

  When “AUTO” is set, the operation waits for the shutter release button 102 (S6 in FIG. 8).

  When the shutter release button 102 is half-pressed here (FIG. 8 (S7)), the CPU 138 obtains the light source type (color temperature of the object field) in the same manner as the white balance correction (FIG. 8 (S8)). ) Determining a white balance correction value (first correction value) suitable for the determined color temperature of the object scene (first color temperature), and a color that is lower by one step than the determined object color temperature White balance correction value (second correction value) suitable for temperature (second color temperature) and white balance correction suitable for color temperature (third color temperature) higher by one step than the obtained color temperature of the object scene A value (third correction value) is determined.

  When the measurement of the color temperature of the object scene is completed, the color temperature measurement completion display lamp 201 displayed in the viewfinder 103 shown in FIG. 9 is turned on (FIG. 8 (S9)).

  Next, the flash emission information is read (FIG. 8 (S10)), and then, when the shutter release button 102 is fully pressed, three flash shootings are performed at a predetermined interval (FIG. 8 (S11)). Details will be described with reference to the timing chart of FIG.

  When the color temperature measurement is completed (FIG. 10A), the CPU 138, together with the light emission amount information, the first color temperature (FIG. 10B), the second color temperature (FIG. 10C), and the third color temperature ( FIG. 10 (d)) is output.

  The system controller 52 receives these pieces of information, determines a strobe light emission amount based on the captured light emission amount information, and outputs a reference value for adjusting the light emission amount to obtain the strobe light emission amount to the dimming circuit 54. To do.

  Further, the RGB ratio data with respect to the color temperature is stored in the memory 25, and the system controller 52 first reads out the RGB ratio corresponding to the first color temperature information from the memory 25 (FIG. 10 (e)). The R, G, and B light emission levels of the LEDs 38R, 38G, and 38B are set so that the strobe light is emitted at the RGB ratio (FIG. 10 (f)).

  Thereafter, when the shutter release button 102 is fully pressed, the flash emission shooting with the light emission amount and the emission color based on the setting information, that is, the flash emission shooting with the first color temperature is performed (FIG. 10G).

  The first image data obtained by photographing in this way is output from the A / D converter 120 via the correlated double sampling circuit (CDS circuit) 118 and temporarily stored in the memory 124 as described above. Stored. In normal shooting, the digital signal processing circuit 126 thereafter performs digital signal processing. However, in the color bracketing shooting mode, in order to give priority to shooting, all the shootings of the number of bracketing frames (here, three images) are stored in the memory 124. Minute) image data is input, and the digital signal processing circuit 126 performs digital signal processing.

  When the photographing of the first image is completed, the system controller 52 immediately reads out the RGB ratio corresponding to the second color temperature information from the memory 25 (FIG. 10 (h)), so that the strobe light is emitted at the read RGB ratio. The R, G, and B light emission levels of the LEDs 38R, 38G, and 38B are set (FIG. 10 (i)).

  When the light emission level setting is completed, the flash light emission photographing with the second color temperature is performed (FIG. 10 (j)).

  When the second image is shot, the system controller 52 immediately reads out the RGB ratio corresponding to the third color temperature information from the memory 25 (FIG. 10 (k)), and the strobe light is emitted with the read RGB ratio. The R, G, and B emission levels of the LEDs 38R, 38G, and 38B are set (FIG. 10 (l)).

  When the light emission level setting is completed, the flash light emission photographing at the third color temperature is performed (FIG. 10 (m)).

  When the shooting of the third image is completed, the three shooting data stored in the memory 124 are subjected to desired digital processing by the digital signal processing circuit 126. Here, the first shooting data is subjected to the first correction. The white balance is corrected by the second correction value for the second image data and the third correction value for the third image data. Thereafter, the data is recorded on the recording medium by the recording unit 156 (FIG. 10 (n)).

  As described above, when the color temperature selection of the color bracketing shooting is set to the automatic selection “AUTO”, the first shooting at the first color temperature is used for the first shooting and the second shooting is performed at the second color temperature. Color bracketing shooting is possible for continuous shooting with strobe lighting and third-color temperature strobe lighting.

  In this embodiment, the color temperature information for three times is input in advance to the system controller 52, but the color temperature information may be input for each photographing. In this embodiment, the strobe light is emitted in the order of the color temperature of the object scene, the color temperature lower than the object object color temperature, and the color temperature higher than the object object color temperature. It may be.

  In the present embodiment, the white balance correction value is different for each shooting, but the white balance value may be fixed and only the color temperature of the strobe may be different. The captured image data is collectively recorded on the recording medium after all the capturing is completed, but may be recorded one by one each time capturing is performed. Further, the number of times of bracketing photographing is not limited to three, and it may be any number.

  Next, the case where the color temperature selection for color bracketing is set to manual selection “M” will be described.

  As shown in FIG. 7, in the setting of “M”, the user can set the center of the color temperature for color bracketing.

  In FIG. 8, since the operations from S1 to S4 are the same as in the case of “AUTO”, the description thereof will be omitted. However, it is assumed that the bracketing correction width is selected in one plus or minus step and three bracketing sheets are selected. .

  In the color temperature selection setting, this time, “M” is set (FIG. 8 (S5)).

  When the color temperature selection is set to “M”, the process proceeds to the color temperature manual setting step (S6 in FIG. 8).

  When the manual setting of the color temperature (FIG. 8 (S12)) is completed and the shutter release button 102 is pressed halfway (FIG. 8 (S13)), the strobe emission information is read based on the manually set color temperature information. After that, when the shutter release button 102 is fully pressed, three flash photography is performed at a predetermined interval (S11).

  Here, manual color temperature setting will be described with reference to FIG.

  FIG. 11 is a detailed flowchart of the manual color temperature setting shown in FIG. 8 (S12).

  When the color temperature selection is set to “M”, the CPU 138 measures the color temperature of the object scene (FIG. 11 (S21)), and when the color temperature measurement is completed, the color temperature measurement completion display lamp is displayed in the liquid crystal finder 103. 201 is turned on and a color temperature set value mark 202 shown in FIG. 9 is displayed (FIG. 11 (S22)).

  Here, the color temperature setting value mark 202 will be described with reference to FIG.

  FIG. 12 is an enlarged view of the color temperature set value mark 202 of FIG. 9, in which seven squares are aligned horizontally, and one of them is displayed in black.

  The central square, that is, the square under the circle indicates the current color temperature of the object scene, the square indicates a settable color temperature, and the square displayed in black indicates the currently set color temperature.

  If the square displayed in black is set at the center (below the circle), the circle will change from white to black to indicate that the object field matches the set color temperature.

  That is, FIG. 12A shows that the center of the color temperature of color bracketing is set to the color temperature of the object scene, and FIG. 12B shows that the center of the color temperature of color bracketing is covered. FIG. 12C shows that the color temperature is set one step lower than the color temperature of the field, and FIG. 12C shows the color temperature center of the color bracketing being two steps higher than the color temperature of the field. Indicates that it is set.

  When the color temperature setting is changed using the camera operation unit 140 (FIG. 11 (S23)), the position of the square displayed in black is changed (FIG. 11 (S24)). Can be set.

  Further, the CPU 138 compares the set color temperature with the color temperature of the object scene (FIG. 11 (S25)), and the set color temperature matches the color temperature of the object scene, that is, a square displayed black. When set to the center, the circle that was white until then is displayed in black, and a notification that the set color temperature matches the color temperature of the object scene is displayed (FIG. 11 (S26, S27)). ).

  In this way, the user can freely set the center of the color temperature for color bracketing using the camera operation unit 140 within a range of plus or minus 3 steps with respect to the color temperature of the object scene while looking at the color temperature set value mark 202. Can be set to

  Here, assuming that the shutter release button 102 is half-pressed in the state set in FIG. 12C (FIG. 8 (S12)), the CPU 138 displays a color that is two steps higher than the already measured color temperature of the object scene. A white balance correction value (first correction value) suitable for the temperature (first color temperature) is determined, and a white balance correction value suitable for a color temperature (second color temperature) that is one step lower than the first color temperature. A white balance correction value (third correction value) suitable for (second correction value) and a color temperature (third color temperature) higher by one step than the first color temperature is determined.

  Thereafter, the color temperature information is input from the CPU 138 to the system controller 52, and bracketing shooting is realized as described above.

  As described above, when the color temperature selection for color bracketing shooting is set to “AUTO”, when the “M” is set, the first shooting is performed with the first color temperature of the strobe. Color bracketing photography is realized in which continuous shooting is performed with the second color temperature strobe emission and the third shot with the third color temperature strobe emission.

  Here, the bracketing correction step and the memory 25 will be described with reference to FIG.

  FIG. 13 is a graph showing the relationship between the color temperature and the ratio of the RBG3 primary colors, the horizontal axis indicates the absolute temperature (K), and the vertical axis indicates the relative intensity of each RGB component.

  As apparent from FIG. 13, the change in RGB ratio is steep in the region where the color temperature is low, but the change in RGB ratio is slow in the region where the color temperature is high.

  Therefore, if the color bracketing amount (correction step) of color bracketing is uniform between the low color temperature and the high color temperature at the center of the bracketing shooting, the color bracketing is performed with the same step amount. Despite shooting, the degree of effect (visual change) is different.

  In the present embodiment, the color temperature dividing step is changed depending on the range of the color temperature. Specifically, it is 100K / 1 step at 4500K or less, 250K / 1 step at a range of 4500K to 6500K, and 500K / at 6500K or more. One step.

  In this way, the amount of color change in one step is visually the same regardless of the color temperature range in which bracketing shooting is performed.

  Further, as described above, the RGB ratio data with respect to the color temperature is stored in the memory 25. However, if the color temperature is divided equally between the low color temperature and the high color temperature, the data is stored. On the temperature side, the change in the RGB ratio with respect to the color temperature is gradual, so that useless memory is increased.

  In the present embodiment, the division step of the color temperature of the stored data is changed depending on the range of the color temperature, so that the memory can be used efficiently.

  As described above, the system controller 52 reads the RGB ratio corresponding to the set color temperature information from the memory 25. More specifically, the system controller 52 sets the closest color temperature among the color temperature steps stored in the memory. The corresponding RGB ratio is read out.

Second Embodiment
As a second embodiment according to the present invention, a camera that does not have a dedicated display relating to the color temperature, such as the color temperature measurement completion display lamp 201 and the color temperature set value mark 202, will be described.

  FIG. 14 is a display in the liquid crystal finder 103 of the camera that does not have a dedicated display regarding the color temperature according to the second embodiment of the present invention.

  What is displayed in the liquid crystal finder 103 is a focus frame. FIG. 14A shows a normal display and FIG. 14B shows a display at the time of focusing.

  Here, the case where the color temperature selection for color bracketing shooting is set to “M” (FIG. 8 (S12)) will be described.

  In the camera of the second embodiment related to the present invention, the coincidence display of the color temperature of the object scene and the set color temperature (FIG. 11 (S27)) is also used as the focus frame in the liquid crystal finder 103. That is, the display shown in FIG. 14A is displayed when the color temperature of the object scene does not match the set color temperature, and the display shown in FIG. 14B is displayed when they match.

  In order to avoid confusion with the focus display, FIGS. 14A and 14B at the time of color temperature display may be blinked.

  When the color temperature of the object scene does not match the set color temperature, the blinking speed in FIG. 14A is changed by the difference between the color temperature of the object scene and the set color temperature, and the color temperature is set. The color temperature position display (FIG. 11 (S24)) may be used instead.

  Further, the display shown in FIG. 14A is always displayed during the color temperature setting, and the display may be blinked only when the color temperature of the object scene matches the set color temperature.

  Further, instead of displaying the focus frame, another display may be used as the coincidence display.

  Further, instead of the display on the liquid crystal finder 103, another display on the liquid crystal monitor 152 may be used.

  In addition, notification by sound may be used instead of visual display.

<Third Embodiment>
A camera according to a third embodiment relating to the present invention will be described with reference to FIGS. 15 and 16.

  FIG. 15 is a flowchart showing the operation of the camera of the third embodiment according to the present invention, and FIG. 16 is a display screen of the liquid crystal monitor 152 of the camera of the third embodiment according to the present invention.

  The camera 100 according to the third embodiment of the present invention shown in FIG. 1 can be set to any one of manual shooting mode, auto shooting mode, and shooting scene selection mode by rotating the mode dial 101. It has become.

  When the mode dial 101 is set to the shooting scene selection mode (FIG. 15 (S31)), the shooting scene selection screen shown in FIG.

  The shooting scene can be selected from a portrait mode, a landscape mode, a sports mode, a night view mode, an evening view mode, and a beach mode, and a desired item is selected by moving the cursor up and down with the cross button 105.

  Here, the sunset mode is a mode for photographing the morning glow or sunset brightly in red, and the beach mode is a mode for photographing on a beach with strong sunlight.

  When the evening scene mode is selected by the cross button 105 (FIG. 15 (S32)) and the menu button 104 is used, the color bracketing shooting mode in the evening scene mode can be set (FIG. 15 (S33)).

  As described above, the evening scene mode is a mode for photographing in red, and it is considered preferable that the strobe light is emitted with a color close to red, that is, with a low color temperature.

  Therefore, when the color bracketing shooting mode is set in the evening scene mode, the strobe emission color temperature is set to, for example, the first color temperature is 3000K, the second color temperature is 2900K, and the third color temperature is 3100K. A low color temperature is set in advance (FIG. 15 (S34)).

  Further, when the beach mode is selected by the cross button 105 (FIG. 15 (S35)) and the menu button 104 is used, the color bracketing photographing mode in the beach mode can be set (FIG. 15 (S36)).

  As described above, the beach mode is a mode for shooting on a beach with strong sunlight, but the beach contains a lot of ultraviolet rays, and the blue sky often appears, so the strobe light is a color close to blue, that is, a high color. It is considered preferable to emit light at a temperature.

  Therefore, when the color bracketing shooting mode is set in the beach mode, the strobe light emission color temperature is set to 10000K, the second color temperature is 9500K, the third color temperature is 10500K, for example. A high color temperature is set in advance (FIG. 15 (S37)).

  When a shooting scene other than that is selected by the cross button 105 and the menu button 104 is used, the color bracketing shooting mode in that mode can be set.

  In other shooting scenes, it is considered that the color temperature of the object scene is standard, so it is preferable that the strobe light is also emitted at the standard color temperature.

  Therefore, when the color bracketing shooting mode is set in other modes (FIG. 15 (S38)), for example, the first color temperature is 5000K, the second color temperature is 4750K, and the third color temperature is 5250K. As described above, the strobe emission color temperature is set to the standard color temperature (FIG. 15 (S39)).

  Based on this information, the operational amplifiers 46, 48, and 50 and the light control circuit 54 are set, and the first image temperature is emitted with the strobe light at the first color, and the second image is emitted with the strobe light at the second color temperature. The third shot is a color bracketing shot that is taken continuously with the strobe emission of the third color temperature.

FIG. 1 is a top view of a camera according to the present invention. FIG. 2 is a rear perspective view of the camera according to the present invention. FIG. 3 is a front perspective view of the camera according to the present invention. FIG. 4 is a block diagram showing an internal configuration of the camera shown in FIG. FIG. 5 is a block diagram showing details of a strobe device built in or externally attached to the camera shown in FIG. FIG. 6 is a timing chart showing the operation of the camera shown in FIG. FIG. 7 is a view showing a liquid crystal display screen of the camera shown in FIG. FIG. 8 is a timing chart showing the operation of the camera shown in FIG. FIG. 9 is a view showing a display in the viewfinder of the camera shown in FIG. FIG. 10 is a timing chart showing the operation of the camera shown in FIG. FIG. 11 is a timing chart showing the operation of the camera shown in FIG. FIG. 12 is an enlarged view of the display in the viewfinder of the camera shown in FIG. FIG. 13 is a graph showing the relationship between the color temperature and the ratio of the RBG3 primary colors. FIG. 14 is a view showing a display in the viewfinder of the camera shown in FIG. FIG. 15 is a timing chart showing the operation of the camera shown in FIG. FIG. 16 is a view showing a liquid crystal display screen of the camera shown in FIG.

Explanation of symbols

  25 ... Memory, 34 ... Light receiving sensor, 38R, 38G, 38B ... LED, 46, 48, 50 ... Operational amplifier, 52 ... System controller, 100 ... Camera, 103 ... Viewfinder, 138 ... CPU, 146 ... Strobe device, 130 ... White Balance adjustment circuit, 152 ... Liquid crystal monitor, 201 ... Color temperature measurement completion display lamp, 202 ... Color temperature set value mark,

Claims (8)

In a camera that shoots continuously at predetermined time intervals in conjunction with a single shutter release operation,
A strobe light source capable of adjusting the color temperature of the emitted strobe light;
Light emission control means for emitting strobe light from the strobe light source in synchronization with each of the continuous photographing,
Color temperature adjusting means for adjusting the color temperature of the strobe light emitted from the strobe light source for each continuous shooting, and different color temperatures within a predetermined color temperature variable range set in advance. Color temperature adjusting means for adjusting the color temperature of the strobe light so that
A camera characterized by comprising   Color temperature detecting means for detecting the color temperature of the object scene, wherein the color temperature adjusting means is within the predetermined color temperature variable range set with the color temperature detected by the color temperature detecting means as the center. The camera according to claim 1, wherein the color temperature of the strobe light is adjusted so as to have different color temperatures.   Color temperature setting means for manually setting a color temperature including a light source type, and the color temperature adjusting means is configured to change the predetermined color temperature set around the color temperature set by the color temperature setting means. 2. The camera according to claim 1, wherein the color temperature of the strobe light is adjusted so as to have different color temperatures within the range.   Scene selection means for selecting a photographic scene, wherein the color temperature adjusting means is configured to have different color temperatures within the predetermined color temperature variable range according to the photographic scene selected by the scene selection means. 2. The camera according to claim 1, wherein the color temperature of light is adjusted.   The camera according to any one of claims 1 to 4, wherein the strobe light source includes light emitting diodes of three colors of R, G, and B.   6. The camera according to claim 5, wherein the color temperature adjusting unit adjusts the color temperature by controlling a ratio of R, G, and B light emission amounts of the three color light emitting diodes.   A storage means for storing a ratio of light emission amounts of R, G, and B of the three color light emitting diodes for emitting strobe light corresponding to each color temperature for each color temperature at a predetermined interval; Reads the ratio of the corresponding R, G, and B emission amounts from the storage means in accordance with the color temperature to be emitted, and the three colors so that the ratio of the read R, G, and B emission amounts is obtained. The camera according to claim 6, wherein each light emission amount of the light emitting diode is controlled. The camera according to claim 7, wherein the storage unit stores a ratio of light emission amounts of R, G, and B at different predetermined intervals according to a color temperature.

Images