JP2005173386A - Camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera with a specific photographic mode, capable of making a skin of a subject look clear, for example, by increasing the light exposure at flash firing and making a subject moderately white in any shooting scene. <P>SOLUTION: The camera has a "beautiful skin" photographic mode, capable of shooting a subject of a human figure made moderately brighter as a specific shooting mode in a forced flashing mode. In a regular forced flashing mode, flashing is regulated so that it is executed at a timing tA, when aperture reaches an aperture value Fno obtained from a distance to the subject and Gno of the flash. In the "beautiful skin" photographic mode, a flash is fired at a timing tb, when the diaphragm value is small; that is, the aperture area is set wider, so that more light reflected by the subject is made incident on a film, and appropriate bright photographing is performed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a camera incorporating a flash device (flash).

  When shooting with a flashlight using a camera incorporating a conventional flashlight device, the flashlight device is based on an appropriate guide number Gno calculated based on subject brightness, shutter aperture value, subject distance, film sensitivity, etc. Shooting is performed under control.

  FIG. 11 is a diagram showing a state of flash emission photographing by a camera incorporating the conventional flash device. In the camera 40 shown in FIG. 11, from the BV value calculated from the output of the photometric device 42 built in the camera, the AV value calculated from Fno of the shutter 43, and the distance L between the subject 44 and the camera 40. Based on the calculated DV value and the SV value calculated from the ISO sensitivity of the film, the GV value and Gno are obtained by the following equations. The flash device 41 is controlled by the Gno, and an appropriate amount of light is emitted toward the subject 44 to perform photographing.

The GV value is
GV = AV + DV-SV + SV100
The above Gno is calculated by
Gno ² = 2 ^GV
Is calculated more. However, SV100 represents the SV value of the film ISO100.

  A recent survey of women's preference for portraits of women shows that it is not always a photo with good exposure, but it is better to have a photo with a slightly larger flash and a whiter face. It has been found that there are more. Therefore, a mode for increasing the amount of light emitted from the flash device in the camera (hereinafter referred to as a skin-beautifying mode) was examined as a shooting mode.

  However, in the above examination, it has been found that if the light emission amount of the flash device is simply increased by a certain amount in the skin beautifying mode, the face may become too white depending on the shooting scene. Furthermore, it is only necessary to provide a flash device that can control the flash emission amount by the camera. However, in the case of a low-cost camera, it is difficult to install such a flash device.

  The present invention has been made to solve such problems, and in any shooting scene, by increasing the amount of exposure during flash emission and appropriately whitening the subject, for example, specific shooting that makes the skin look beautiful An object is to provide a camera having a mode.

  According to a first aspect of the present invention, there is provided a light projecting means for projecting a light beam toward a subject, an aperture control means for controlling a shutter aperture value, and a correction value calculating means for calculating a correction amount of the aperture value. When a specific shooting mode is selected in which the face of the subject person is the main shooting target and light is always projected, the aperture control means sets the calculated correction value to Based on this, the aperture value is changed.

  According to a second aspect of the present invention, in the camera according to the first aspect, the aperture control means reduces the aperture value in accordance with the correction value when the specific shooting mode is selected than when in the normal shooting mode. To control.

  The camera according to claim 3 of the present invention is the camera according to claim 2, further comprising photometric means for photometrically measuring the brightness of the subject, wherein the correction value calculating means uses the photometric means to measure the correction value. Calculate according to the results.

  According to a fourth aspect of the present invention, in the camera according to the third aspect, the correction value calculation means uses the difference between the peripheral photometry result and the central photometry result obtained by the photometry means as the photometry result to determine the correction value. calculate.

  According to a fifth aspect of the present invention, in the camera according to the third aspect, the correction value calculating means calculates a small value as the correction value when the subject is bright.

  The camera according to a sixth aspect of the present invention is the camera according to the first aspect, further comprising a distance measuring means for measuring a distance to the subject, and a photographing magnification from the distance to the subject and the focal length of the photographing lens. Magnification correction means, and the correction value calculation means calculates the correction value according to the photographing magnification.

  The camera according to claim 7 of the present invention is the camera according to claim 1, further comprising a photometric means for measuring the brightness of the subject, a distance measuring means for measuring the distance to the subject, and a distance to the subject. Magnification calculating means for calculating a photographic magnification from the focal length of the photographic lens, and the correction value calculating means calculates the correction value according to the photometric result of the photometric means and the photographic magnification.

  The camera according to claim 8 of the present invention is the camera according to claim 6 or 7, wherein the correction value calculation means calculates a small value as the correction value when the photographing magnification is large.

  The camera according to claim 9 of the present invention is the camera according to claim 1, further comprising photometric means for measuring the brightness of the subject and distance measuring means for measuring the distance to the subject. The value calculation means calculates the correction value according to the photometry result by the photometry means and the distance measurement result by the distance measurement means.

  According to a tenth aspect of the present invention, in the camera according to the first aspect, the camera further comprises a photometric means for measuring the brightness of the subject, and the correction value calculating means determines the correction value as a photometric result of the photometric means. And is calculated according to the focal length of the taking lens.

  According to the present invention, the aperture value at the time of flash emission is controlled to increase the amount of flash light that is reflected by the subject and incident on the film, and the face is appropriately whitened so that the skin can be beautifully taken in any shooting scene. A camera having a specific shooting mode can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Prior to detailed description of the embodiments, an outline of a camera according to the technique of the present invention will be described with reference to FIG.

  A camera according to the technique of the present invention includes a light projecting unit that projects a light beam toward a subject, an aperture control unit that controls an aperture value of the shutter, and a correction value calculation unit that calculates a correction amount of the aperture value. When a specific shooting mode in which a person's face is the main shooting target and a constant light emission is performed, that is, a specific forced light emission mode is selected, the aperture control means performs the calculated correction. Control is performed to change (decrease) the aperture value based on the value, and photographing is performed.

FIG. 1 is a diagram showing the opening area of a shutter of a camera and the light emission timing of a flash (light projection means) according to the technique of the present invention. When shooting in the normal forced flash mode, if the ISO sensitivity of the film is constant, the flash emission timing is the aperture value Fno determined by the distance to the subject of the following equation and the flash Gno. It is controlled by the aperture control means so as to emit light at the timing tA of 1.
Aperture value Fno = Gno / distance to subject The aperture area SA is proportional to the reciprocal of the square of the aperture value Fno.

  On the other hand, when a specific forced light emission mode is selected in the camera, the aperture control means controls so that more light reflected from the subject is incident on the film than in the normal mode. The flash is emitted at a timing tb at which the aperture value becomes smaller (a larger shutter opening area Sb). As described above, in the specific forced light emission mode, exposure is performed with a light amount larger than a normal flash light amount, and brighter photographing is performed. As the specific forced light emission mode, specifically, there is a beautiful skin photographing mode. This photographing mode is a flash photographing mode for photographing a woman's skin more beautifully.

Next, the camera of the first embodiment of the present invention will be described.
FIG. 2 is a block configuration diagram of the electric control circuit of the camera of the first embodiment.

  The camera 50 according to the present embodiment is a camera equipped with a lens shutter type shutter that is often used in a compact camera and in which the shutter also functions as an aperture.

  The electric control circuit of the camera 50 according to the present embodiment includes a CPU 1 which is a microcomputer that controls the whole, and the CPU 1 includes an EEPROM 2, an EXT terminal 3, a PWSW 4, a BKSW 5, an RWSW 6, a 1RSW 7, a 2RSW 8, a ZUSW 9, a ZDSW 10, a MODSW 11, LCD 12, flash circuit 13, distance measuring circuit 16, photometric circuit 20, zooming drive circuit 23, zooming drive signal detection circuit 25, focusing drive circuit 26, focusing drive signal detection circuit 28, shutter drive circuit 29, shutter drive signal detection circuit 31 A film feed drive circuit 32, a film movement amount detection circuit 34, and a film information detection circuit 35 are connected.

  The EEPROM 2 is a non-volatile memory for storing parameters and camera state necessary for controlling the camera.

  The EXT terminal 3 is an external communication terminal for externally controlling the camera at the time of executing various adjustments performed at the time of manufacturing or photographing at the time of camera operation and performance guarantee.

  The PWSW 4 is a switch for turning on / off the camera. The camera is turned on when the PWSW 4 is turned on, and the power is turned off.

  The BKSW 5 is a switch for detecting an open / closed state of a rear cover (not shown) for loading and unloading a film. The ON state indicates a rear cover open state, and the OFF state indicates a rear cover closed state. Show.

  The RWSW 6 is a switch for executing forced rewind when it is normally turned off and is turned on.

  The 1RSW7 and 2RSW8 constitute a two-stage release switch, and after the 1RSW7 is turned on, the 2RSW8 is turned on. The 1RSW 7 is a switch for starting distance measurement and photometry as exposure preparation operations when it is normally turned off and is turned on. 2RSW8 is a switch for starting an exposure operation when it is normally turned off and is turned on.

  The ZUSW 9 is a switch for starting zooming drive so as to change the focal length to the telephoto side when the ZUSW 9 is normally turned off and is turned on.

  The ZDSW 10 is a switch for starting zooming drive so as to change the focal length to the wide angle side when it is normally turned on and turned on.

  The MODSW 11 is a switch that switches the shooting mode when the MODSW 11 is normally off and is turned on. For example, the MODSW 11 can switch the shooting mode to normal auto shooting, normal forced light emission mode, and skin softening mode. .

  The LCD 12 is an external display means for performing camera mode display, frame number display, and the like.

  The flash circuit 13 is a light projecting means, and the flash circuit 13 stores an Xe tube 14 that is a light source for illuminating a subject and electrical energy for illumination in order to keep exposure appropriate. A main capacitor 15 is connected. Note that the camera 50 is a low-price camera, and the flash circuit 13 does not perform flash emission control.

  The AF sensor 16 is a distance measuring unit and outputs a signal related to the subject distance L from the camera 50 to the subject 19. An image of the subject 19 obtained through a pair of the light receiving lenses 17a and 17b arranged with a base line length (parallax) B apart is used as the pair of sensor arrays 18a and 18b arranged at the position of the focal length f. The CPU 1 detects the subject distance L from the image position difference X based on this parallax, according to the known triangulation principle. Note that the relative position of the image position changes with respect to the optical axes of the pair of sensor arrays 18a and 18b depending on the size of the subject distance L.

  The photometric circuit 20 is a photometric means, to which the light receiving elements 21a and 21b are connected. The photometric circuit 20 measures the amount of light near the subject incident through the photometric lens 22, and measures the subject brightness for determining the exposure condition. To do. The light receiving element 21a measures the periphery of the shooting screen, and the light receiving element 21b measures the center of the shooting screen.

  The zooming driving circuit 23 drives the zoom motor 24 under the control of the CPU 1, and the motor driving force is applied to a zooming optical system (focusing lens) of a photographing lens (not shown) through a gear train (not shown). It is transmitted and zooming is performed.

  The zooming drive signal detection circuit 25 generates a pulse signal corresponding to the rotation amount of the zoom motor 24 and transmits the pulse signal to the CPU 1. The CPU 1 generates data corresponding to the focal length by counting the pulse signals.

  The focusing drive circuit 26 drives a focusing motor 27 under the control of the CPU 1, and the motor driving force is transmitted to a focusing optical system of a photographing lens (not shown) via a gear train (not shown). Is done.

  The focusing drive signal detection circuit 28 generates a pulse signal corresponding to the rotation amount of the focusing motor 27 and transmits the pulse signal to the CPU 1. The CPU 1 performs control for accurately stopping the focusing lens at the in-focus position by detecting the number and period of the pulse signals.

  The shutter drive circuit 29 performs energization control to the plunger 30 for driving a shutter (not shown) under the control of the CPU 1. The CPU 1 controls the energization time to the plunger 30, whereby the exposure amount is controlled.

  The shutter drive signal detection circuit 31 generates a reference timing for controlling the energization time to the plunger 30 in conjunction with the shutter operation.

  The film feeding drive circuit 32 drives the film feeding motor 33 under the control of the CPU 1, and winds and rewinds the film.

  The film movement amount detection circuit 34 detects the perforation formed on the film (not shown) to detect the film feeding state and outputs it to the CPU 1.

  The film information detection circuit 35 reads ISO sensitivity information provided in the film cartridge 36 and outputs it to the CPU 1.

  The CPU 1 is a control unit that controls the entire camera, and further includes an aperture control unit that controls the aperture value of the shutter, and a correction value calculation unit and a magnification calculation unit that calculate a correction amount of the aperture value. When a specific shooting mode (a skin-beautifying mode to be described later) is selected in which a person's face of the subject is a main shooting target and light is always projected as described later, The aperture value correction value is calculated by the correction value calculation unit according to the focal length information by the focal length detection unit and / or the subject distance information by the photometry unit and / or the photometry information by the photometry unit and the film sensitivity information. Control is performed to change (decrease) the aperture value based on the correction value.

Next, shooting sequence processing in the camera 50 of the present embodiment will be described with reference to FIGS.
3 and 4 are flowcharts of the PWRST process that is the main routine of the shooting sequence in the camera 50 of the present embodiment. FIG. 5 is a flowchart of a release process of a subroutine called by the main routine of FIG. FIG. 6 is a flowchart of an exposure amount calculation process of a subroutine called in the release process of FIG. FIG. 7 is a flowchart of the AVF correction process of the subroutine called in the exposure amount calculation process of FIG. FIG. 8 is a diagram showing a relationship between a predetermined peripheral luminance at the time of shooting and an AVF correction amount.

  When the power is turned on when the PWSW 4 is turned on, processing of each step of PWRST, which is the main routine of the imaging sequence shown in FIGS. 3 and 4, is started under the control of the CPU 1.

  First, initial setting is performed in step S1 shown in FIG. Here, the above-described initialization of the CPU 1, initialization of each input / output port, RAM, and the like are performed. In step S2, external communication is performed by the EXT terminal 3. Next, in step 3, the data stored in the EEPROM 2 is read and stored in the RAM in the CPU 1 described above.

  Next, in step S4, it is determined whether or not the state of the BKSW 5 has changed, and if it has changed, the process proceeds to step S5. If not, the process proceeds to step S9.

  In step S5, it is determined whether or not the current state of BKSW5 is an off state. If not in the off state, the process proceeds to step S6. In this case, since the state of BKSW5 has changed and the current state is on, BKSW5 has changed from off to on. That is, it indicates that the rear lid is changed from the closed state to the open state. Therefore, in step S6, when it is “1”, the flag F BKCLOS indicating that the rear lid is in the closed state is set to “0”, the open state is stored, and the process proceeds to step S9.

  If it is determined in step S5 that the state of BKSW5 is OFF, the process proceeds to step S7, where “1” is set to the flag F BKCLOS described above, and the fact that the rear lid is closed is stored. In step S8, since the rear cover is changed from the open state to the closed state, there is a possibility that the film is set. Therefore, an autoload process is performed, and the process proceeds to step S9.

  In step S9, the state of the flag F WNDREQ indicating that one frame winding is necessary when “1” is determined. When the state of F WNDREQ is “1”, the process proceeds to step S10, performs a one-frame winding operation, and proceeds to step S11. When the state of the flag F WNDREQ is “0”, the process proceeds to step S13 as it is.

  In step S11, it is determined whether or not a film end has been detected during the winding of one frame in step S10. When the film end is not detected, the process proceeds to step S13, and when the film entry is detected, the process proceeds to step S12. In step S12, since the film end is detected, a rewinding operation is necessary, and a flag FRWREQ indicating that rewinding is necessary is set to “1”, and the process proceeds to step S13.

  In step S13, the state of the flag F RWREQ is determined. When F RWREQ is “1”, it means that rewinding is necessary, so that the process proceeds to step S14, performs the rewinding process, and proceeds to step S15. If F RWREQ is “0” in the determination in step S13, it is a case where rewinding is unnecessary, and the process directly proceeds to step S15.

  In step S15, the state of PWSW4 is determined. If the state of PWSW4 is off, it is in a power off state, so the process proceeds to step S17 to perform a collapsing process for moving the lens frame to the stowed state, and then a display off process for turning off the LCD 12 in step S18. Then, the CPU 1 shifts to a stop state where the operation of the CPU 1 is stopped. In order to return from this stop state, the control operation of the CPU 1 is resumed from step S1 which is the head of the PWRST process of this routine by the operation of PWSW4, BKSW5 and RWSW6.

  If it is determined in step S15 that the PWSW 4 is in the on state, the power on state is indicated, so the process proceeds to step S19 in FIG. 4 to perform a setup process for moving the lens frame to the light position in the photographing state. Subsequently, in step S20, the state change of each switch of PWSW4, BKSW5, RWSW6, 1RSW7, 2RSW8, ZUSW9, ZDSW10 and the current state are detected.

  Next, in step S21, the LCD 12 is operated, and display on processing for performing necessary display is executed.

  Further, in step S22, it is determined whether or not the state of PWSW4 has changed. If so, the process jumps to step S1, which is the head of the PWRST process of this routine. If it is determined in step S22 that the state of PWSW4 has not changed, the process proceeds to step S23 to determine whether or not the state of BKSW5 has changed. If the state of BKSW5 has changed, the CPU shampoos to step S1, which is the head of the PWRST process of this routine. If it is determined in step S23 that the state of BKSW5 has not changed, the process proceeds to step S24 to determine whether or not the state of RWSW6 has changed. If the state of the RWSW 6 has not changed, no rewinding process is required, and the process proceeds to step S29. If the state of RWSW 6 has changed, the process proceeds to step S26.

  In step S26, it is determined whether or not the state of RWSW 6 is currently on. If the RWSW 6 is off, the process proceeds to step S29. If the state of the RWSW 6 is on, the process proceeds to step S27.

  In step S27, the state of the flag F BKCLOS indicating the current state of the rear lid is determined. If the flag F BKCLOS is “1”, the process proceeds to step S28. When F BKCLOS is “1”, this indicates that the rear lid state is the closed state, and here, it is when the RWSW 6 changes from the off state to the on state when the rear lid is in the closed state. . That is, since the rewinding process is necessary, “1” is set to the flag FRWREQ indicating that the rewinding process is necessary, and the process returns to step S9 in FIG. As described above, branching to step S14 is performed based on the determination in step S13, and the rewinding process is executed. If F BKCLOS is “0” in the determination in step S27, the rear lid state is the open state, and the process directly returns to step S9 in FIG.

  In step S29, the flash circuit 13 described above is operated to charge the main capacitor 15 with energy for flash emission. The external communication process in the next step S30 is the same as that in step S2. Further, in step S31, a subroutine mode change process is called and executed. The mode set here includes, for example, a normal photographing mode, a normal forced light emission mode, and a skin beautification mode that is a specific forced light emission mode.

  Subsequently, in step S32, it is checked whether there is a release request. That is, it is determined whether 1RSW 7 has changed from the off state to the on state. When the state changes from the off state to the on state, that is, when there is a release request, the process proceeds to step S40, and the exposure preparation operation and the release processing of the subroutine for performing the exposure operation are called. If 1RSW7 has not changed to the ON state, that is, if there is no release request, the process proceeds to step S33. The release process will be described later with reference to FIG. When an exposure operation is performed during the release process, “1” is set to a flag F WNDREQ indicating that a winding operation is required during the release process. In order to perform the process according to the state of the flag F WNDREQ, the process proceeds to step S9 after the release process is executed. In step S9, as described above, when the flag F WNDREQ is “1”, the process proceeds to step S10, and a one-frame winding operation is performed.

  When the process proceeds to step S33, it is checked whether or not there is a zoom drive request. That is, it is determined whether any of ZUSW9 and ZDSW10 has changed from the off state to the on state. When either ZUSW9 or ZDSW10 changes from the off state to the on state, that is, when there is a zoom request, the zoom drive circuit 23 is controlled to execute the zoom drive process of step S34 for performing the zoom control operation. If there is no zoom request, the process returns to step S20 as it is, and also returns to step S20 after the zoom drive process of step S34 to form a main loop.

Here, details of the release process of the subroutine called in step S40 described above will be described with reference to the flowchart of FIG.
This release process is also executed under the control of the CPU 1. First, in the distance measuring process in step S41, the AF sensor 16 is controlled to measure the distance to the subject as described above. The measured result is output as data proportional to the reciprocal of the distance, and stored in LDATA, which is a RAM in the CPU 1. In the photometry process of step S42, the photometry circuit 20 is controlled to measure the luminance of the central portion of the shooting scene and the luminance of the peripheral portion (hereinafter referred to as peripheral luminance). In step S43, a lens extension amount calculation is performed to calculate the focusing lens extension amount necessary for focusing from the zoom position and the reciprocal of the distance. In step S44, a subroutine exposure amount calculation process is called. In the exposure amount calculation process, the shutter control time and the strobe light emission amount are calculated based on the subject luminance measured in step S42, and details thereof will be described later with reference to the flowchart of FIG. .

  Subsequently, in step S45, the switch state for detecting the states of 1RSW7 and 2RSW8 is read. The states of 1RSW7 and 2RSW8 read here are determined in subsequent steps S46 and S47. First, in step 46, it is determined whether 1RSW7 is turned off. When 1RSW7 is turned off, 2RSW8 is turned off without being turned on, and the release operation by this release process is terminated. When 1RSW7 is not turned off, it is a case where the ON state of 1RSW7 is continued, the process proceeds to step S47, and the state of 2RSW8 is determined.

  If it is determined in step S47 that the 2RSW 8 is not in the on state, the process returns to step S45 again to perform a switch state reading process. If it is determined in step S47 that the 2RSW 8 is on, the exposure operation needs to be started, and the process proceeds to the next step S48. From step S45 to step S47 described above, the process until 1RSW7 is turned off or 2RSW8 is turned on is looped.

  In step S48, focusing lens drive control is executed in accordance with the focusing lens drive amount (feed-out amount) calculated in step S43, and the photographing lens is brought into focus. Subsequently, in step S49, the exposure operation is executed according to the shutter control time based on the exposure amount calculated in step S44 and the flash light emission amount. In step S50, since the exposure operation has been completed, lens position reset control for returning the focusing lens to the initial position is performed. In step S51, “1” is set to a flag F WNDREQ indicating that the winding control is necessary to wind up the photographing frame that has been exposed, the release process is terminated, and the process returns to the main routine.

Here, the details of the exposure amount calculation of the subroutine called in step S44 described above will be described with reference to the flowchart of FIG.
The values relating to APEX (SV value, AV value, TV value, DV value, GV value, EV value) used in the following description are the ISO sensitivity of the film, aperture Fno, shutter time SS, subject distance L, It is defined as follows by Gno of the flash guide number. That is,
SV = log ₂ (ISO sensitivity × 0.32) (1)
AV = log ₂ (Fno ² ) (2)
TV = log ₂ (l / SS) (3)
DV = log ₂ (L ² ) (4)
GV = log ₂ (Gno ² ) (5)
EV = AV + TV = BV + SV (6)
And

  This exposure amount calculation process is also executed under the control of the CPU 1. First, in step S53, the SV value of the film is calculated from the DX code of the film cartridge. In step S54, the DV value is calculated using the distance measurement result in step S41 (data proportional to the reciprocal of the distance). In step S55, each BV value is calculated from the subject luminance and the peripheral luminance which are the photometric results in step S42. In step S56, the AV value when the shutter is opened is obtained from the current zoom position. In step S57, the EV value is obtained from the BV value and the SV value described above.

  In step S58, whether or not flash light emission is necessary is determined based on the EV value or the mode such as the skin beautifying mode or the forced light emitting mode. The skin beautifying mode is the function of the present invention mounted on the camera 50. This will be described later in detail with reference to FIG.

  In step S59, a TV value is calculated from the EV value and the AV value.

In step S60, an AVF as an AV value at the time of flash emission is calculated. This AVF value is given by
AVF = GV−DV−ISO100 SV + SV (7)
Sought by.

  In step S61, a subroutine AVF correction process is called. In this AVF correction process, when the selection mode is the skin beautifying mode, the AVF correction obtained in step S60 is performed (details will be described later).

  In step S62, the shutter control time is calculated from the TV value obtained in step S59, and the exposure amount calculation process is terminated.

Details of the AVF correction processing in the skin-beautifying mode called in step S61 described above will be described with reference to the flowchart of FIG.
Studies have shown that Japanese women tend to prefer photos that are moderately overexposed when flashing. The reason for this is that the above-exposed overexposure eliminates the stains and wrinkles on the face and makes the skin appear white. The skin beautification shooting mode is a forced light emission shooting mode using the effect.

  In the skin-beautifying mode according to the present embodiment, in order to overexposure properly during flash emission, the flash that is reflected by the subject and incident on the film is reduced by reducing the aperture value, rather than increasing the flash emission amount. The amount of light was increased so that the exposure was moderately overexposed. Therefore, it is possible to incorporate this beautiful skin photographing mode even with an inexpensive camera that does not have a function of controlling the amount of flash light.

  However, it has been found through experimental studies that it is not possible to reduce the amount of flash reflected by the subject and incident on the film appropriately by simply reducing the aperture value by a fixed amount. The reason for this is that the amount of correction (white balance in the case of a digital camera) differs depending on the size and brightness of the subject on the screen. In a scene, the subject may be overexposed and it may not even be possible to determine what is in the picture.

  In order to solve the above problem, in the present embodiment, the AV value (AVF) at the time of flash emission is set so that any scene is appropriately over by correcting the AVF by the AVF correction processing described below. ) To control the amount of flash light that is reflected by the subject and incident on the film.

  Therefore, in this AVF correction process, when correction control of AVF, which is an AV value at the time of flash emission, is started, it is determined whether or not the skin softening mode is selected in step S65 as shown in FIG. If the skin beautifying mode is selected, the process proceeds to step S66; otherwise, the present subroutine is terminated.

In step S66, using the subject distance L obtained by the AF sensor 16 and the focal length counted by the zoom driving signal detection circuit 25,
Shooting magnification = focal length / subject distance (8)
Obtain the magnification.

In step S67, an AVF correction amount is selected from the table shown in Table 1 below based on the photographing magnification obtained in step S66, and a correction amount for the photographing magnification is obtained.

  Table 1 is a table that is stored in the EEPROM 2 and shows the photographing magnification dependency obtained by setting the relationship between the photographing magnification and the AVF correction amount through various experimental studies. As shown in Table 2, it has been found from the above examination that the larger the shooting magnification, the better the correction amount. Here, the reason why the reference method from the table is used to calculate the correction amount is that the relationship between the photographing magnification and the correction amount is not a straight line. If linear approximation is used, it is necessary to perform correction with a plurality of straight lines.

Subsequently, in step S68, based on the peripheral brightness BV of the subject,
AVF correction amount by luminance = −0.1503 × peripheral luminance BV + 1.4196 (9)
Is used to calculate the correction amount by luminance. Equation (9) is also stored in the EEPROM 2.

  The gradient in the relational expression (9) and the peripheral luminance BV that gives a correction amount of 0 are set based on the results of experimental studies. FIG. 8 is a graph showing the relationship of equation (9) with the horizontal luminance BV value on the horizontal axis and the AVF correction amount by luminance on the vertical axis.

  In step S69, the AVF correction amount based on the photographing magnification obtained in step S67 and the AVF correction amount based on the peripheral luminance obtained in step S68 are added to obtain a total AVF correction amount for the AV value (aperture value) during flash emission. . Here, if the result of addition is a negative number, the correction amount is set to zero.

Table 2 shown below is a table showing total correction amount values actually obtained with respect to the BV value of the surrounding luminance and the photographing magnification.

  In Table 2, the row direction indicates the BV value of the peripheral luminance, the column direction indicates the photographing magnification, and the numerical values described in the table indicate the total AVF correction amounts.

In step S70, the AVF value in the beautiful skin photographing mode is corrected by the total AVF correction amount obtained in step S69. That is,
Correction AVF = AVF before correction + AVF correction amount (10)
To correct the AVF value in the beautiful skin photographing mode. Note that if the corrected AVF value in the beautiful skin photographing mode is smaller than the open AV value, the open AV value is set.

  After obtaining the corrected AVF value, the AVF correction process is terminated, and the process returns to the exposure amount calculation process of FIG.

  According to the camera 50 of the first embodiment described above, in the state in which the skin beautifying mode is selected, the equations (8), (9), and (10) are calculated based on the measured photographing magnification and the peripheral luminance. By applying and correcting the AVF value, it is possible to control the exposure amount (exposure amount) at the time of flash emission so that it will be adequately exceeded in any scene, and beautifully make women's skin without white spots etc. It becomes possible to shoot. Further, since the exposure amount at the time of flash emission is controlled by the diaphragm, the skin softening mode according to the present embodiment can be incorporated into an inexpensive camera that does not have the function of controlling the amount of flash light.

  Next, a camera according to a second embodiment of the present invention will be described with reference to FIGS.

  The camera 50 of the first embodiment described above is an example in which the AVF value is corrected according to the photographing magnification and the peripheral luminance. However, in the case of a camera having a single focus photographing lens without a zoom mechanism with a constant photographing magnification, even when the AVF value is corrected with the subject distance and the peripheral luminance, it is the same as in the case of the camera of the first embodiment. The effect is obtained. As described above, the camera according to the present embodiment is capable of photographing in the skin softening mode with a camera having a single focus photographing lens without a zoom mechanism.

  The electrical configuration of the camera of this embodiment is the same as that of the first embodiment except that the zooming drive circuit 23, zoom motor 24, and zooming drive signal detection circuit 25 are omitted from the block diagram of FIG. It has the same configuration as the camera. The same components will be described below using the same reference numerals as those in FIG.

  The main routine of the shooting sequence process in the camera of this embodiment is a routine obtained by removing steps S33 and S34 from FIGS. Further, the subroutine release process and the exposure amount calculation process are the same as the routines shown in FIGS. 5 and 6, but the subroutine AVF value correction process called in the exposure amount calculation process is shown in the flowchart of FIG. The AVF value correction processing shown is applied.

  That is, when the AVF value correction process of the subroutine shown in FIG. 9 is called in step S61 of the exposure amount calculation process, the exposure amount calculation process is started under the control of the CPU 1. First, in step S72, it is determined whether the selection mode is the skin beautifying mode. If the skin softening mode is selected, the process proceeds to step S73. If the skin softening mode is not selected, this subroutine is terminated.

In step S73, the AVF correction amount is selected from the table shown in the following Table 3 based on the subject distance L obtained by the AF sensor 16, thereby obtaining the correction amount based on the subject distance L.

  Table 3 shows the relationship between the subject distance and the AVF correction amount, which is a table obtained based on data set by various experimental studies, and is stored in the EEPROM 2.

  In step S74, a correction amount based on luminance is calculated based on the peripheral luminance of the shooting scene. Equation (9) is applied to the calculation formula for the correction amount based on the luminance, as in the case of the first embodiment.

  In step S75, the AVF correction amount based on the subject distance obtained in step S73 and the AVF correction amount based on the peripheral luminance obtained in step S74 are added to obtain a total correction amount. Again, when the result of the addition is a negative number, the correction amount is set to zero.

  In step S76, the AVF value is corrected with the total correction amount obtained in step S75. Then, the AVF correction process of this subroutine is terminated.

  According to the camera of the present embodiment, the same effects as in the case of the camera 50 of the first embodiment can be obtained. However, particularly in the case where the subject distance changes, it is possible to perform good photographing in the skin-beautifying photographing mode. Further, even if the camera is a single focus camera and does not control the flash light emission amount, it is possible to shoot in the skin beautifying mode.

  Next, a camera according to a third embodiment of the present invention will be described with reference to FIGS.

  For a camera that does not have an AF (autofocus) function, the AVF value during flash emission is corrected based on the focal length information obtained from the output signal of the zooming drive signal detection circuit 25 in the camera 50 of the first embodiment. However, the same effect as that of the camera of the first embodiment can be obtained at the time of photographing beautiful skin. The camera of this embodiment is applied to a zoom camera that does not have an AF function as described above.

  The electrical configuration of the camera of the present embodiment is the same as that of the camera of the first embodiment except that the AF sensor 16 is deleted from the block configuration diagram of FIG. The same components will be described below using the same reference numerals as those in FIG.

  The main routine of the shooting sequence process in the camera of the present embodiment is the same routine as in FIGS. Regarding the release process of the subroutine, it is assumed that the distance measurement process in step S41 of the routine of FIG. In the subroutine exposure amount calculation process, the DV value calculation process in step S64 of the routine of FIG. 6 is eliminated. Furthermore, the AVF correction process of the subroutine needs to be changed to the process of selecting the AVF correction amount from the focal length information instead of the process of selecting the AVF correction amount based on the subject distance L in step S73 of the routine of FIG. is there.

That is, by selecting an AVF correction amount from the table shown in Table 4 at step S73 of the AVF correction process of the subroutine shown in FIG. 9, the correction amount based on the focal length is obtained.

  Table 4 shows the relationship between the focal length information (wide, standard, tele) and the AVF correction amount, which is a table obtained based on data set by various experimental studies, and is stored in the EEPROM 2. .

  According to the camera of the present embodiment, the same effects as in the case of the camera 50 of the first embodiment can be obtained, but good photographing can be performed particularly in the skin-beautifying mode corresponding to the change in the focal length. Further, even if the camera does not have an AF function and does not perform flash light emission amount control, it is possible to perform photographing in the skin beautifying mode.

  Next, a camera according to a fourth embodiment of the present invention will be described with reference to FIGS.

  The camera 50 of the first embodiment described above is an example in which the AVF value at the time of flash emission is corrected according to the photographing magnification and the peripheral luminance. The camera of the present embodiment corrects the AVF value based on the photographing magnification and the luminance difference between the central part and the peripheral part of the photographing scene. Similar effects can be obtained.

  The electrical configuration of the camera of this embodiment is the same as that of the camera 50 of the first embodiment shown in the block configuration diagram of FIG. 2, and the same reference numerals as those in FIG. explain.

  The main routine of the shooting sequence process in the camera of the present embodiment is based on the same flowchart as in FIGS. The subroutine release process and exposure amount calculation process are the same as the routines shown in FIGS. 5 and 6. The subroutine AVF value correction process called in the exposure amount calculation process is shown in the flowchart of FIG. The AVF value correction process shown in FIG.

  When the subroutine AVF value correction process is called in step S61 of the exposure amount calculation process, it is determined in step S78 whether the selection mode is the beautiful skin photographing mode under the control of the CPU 1 as shown in FIG. If the skin softening mode is selected, the process proceeds to step S79. If the skin softening mode is not selected, this subroutine is terminated.

  In step S79, the AVF correction amount is selected from the same table as in Table 1 based on the shooting magnification obtained by the AF sensor 16, thereby obtaining the correction amount based on the shooting magnification.

  In step S80, the AVF correction amount based on the luminance difference is calculated using a predetermined calculation formula based on the luminance difference between the central luminance and the peripheral luminance of the shooting scene.

  In step S81, the AVF correction amount based on the photographing magnification obtained in step S79 and the AVF correction amount based on the luminance difference obtained in step S80 are added to obtain a total correction amount. Again, when the result of the addition is a negative number, the correction amount is set to zero.

  In step S82, the AVF value is corrected with the total correction amount obtained in step S81. Then, the AVF correction process of this subroutine is terminated.

  According to the camera of the present embodiment, the same effect as the effect in the skin beautifying mode in the camera 50 of the first embodiment can be obtained.

  Even if the AVF value is corrected only by the shooting magnification or only by the peripheral luminance except for the AVF value correction method in the camera of each embodiment described above, the effect is the same as in the case of the above embodiment, but it is the same. Such effects can be obtained. In addition to these embodiments, various modifications can be made without departing from the scope of the present invention.

  In addition, the gist of the present invention can be applied not only to a camera that takes a picture with a silver salt film but also to a digital camera that takes an image of an object with an imaging element.

  The camera according to the present invention can be used as a camera capable of photographing in the skin-beautifying photographing mode in which the aperture value is controlled in a specific photographing mode for performing flash photographing.

It is a figure which shows the opening area of the shutter of the camera by the technique of this invention, and the light emission timing of a flash (light projection means). It is a block block diagram of the electric control circuit of the camera of 1st embodiment of this invention. FIG. 3 is a part of a flowchart of a PWRST process that is a main routine of a photographing sequence in the camera of FIG. 2. FIG. FIG. 9 is another part of a flowchart of PWRST processing that is a main routine of a photographing sequence in the camera of FIG. 2. 5 is a flowchart of a release process of a subroutine called in the main routine of FIG. 4 in the camera of FIG. 6 is a flowchart of an exposure amount calculation process of a subroutine called in the release process of FIG. 5 in the camera of FIG. It is a flowchart of the AVF correction process of the subroutine called by the exposure amount calculation process of FIG. 6 in the camera of FIG. FIG. 3 is a diagram showing a relationship between predetermined peripheral luminance and AVF correction amount at the time of shooting with the camera of FIG. 2. It is a flowchart of the correction process of the AVF value which is a subroutine in the imaging | photography sequence of the camera of 2nd embodiment of this invention. It is a flowchart of the correction process of the AVF value which is a subroutine in the imaging | photography sequence of the camera of 4th embodiment of this invention. It is a figure which shows the state of the flash light emission imaging | photography with the camera incorporating the conventional flash device.

Explanation of symbols

1 ... CPU
(Aperture control means, correction value calculation means,
Magnification calculation means)
13: Flash circuit (light projection means)
16: AF sensor (ranging means)
20: Photometric circuit (photometric means)

Agent Patent Attorney Susumu Ito

Claims (10)

A light projecting means for projecting a light beam toward the subject;
Aperture control means for controlling the aperture value of the shutter;
Correction value calculating means for calculating a correction amount of the aperture value;
When a specific shooting mode is selected in which the face of the subject person is the main shooting target and light is always emitted, the aperture control means is based on the calculated correction value. A camera characterized by changing the aperture value.   2. The camera according to claim 1, wherein the aperture control means controls the aperture value to be decreased according to the correction value when the specific shooting mode is selected than when the normal shooting mode is selected.   3. The camera according to claim 2, further comprising photometric means for measuring the brightness of the subject, wherein the correction value calculating means calculates the correction value according to a photometric result obtained by the photometric means. .   4. The camera according to claim 3, wherein the correction value calculation means calculates the correction value by using a difference between a peripheral photometry result and a central photometry result obtained by the photometry means as the photometry result.   4. The camera according to claim 3, wherein the correction value calculation means calculates a small value as the correction value when the subject is bright. Furthermore, a distance measuring means for measuring the distance to the subject,
Magnification calculating means for calculating the photographic magnification from the distance to the subject and the focal length of the photographic lens;
The camera according to claim 1, wherein the correction value calculation means calculates the correction value according to the photographing magnification. Furthermore, a metering means for metering the brightness of the subject,
Ranging means for measuring the distance to the subject;
Magnification calculating means for calculating a photographing magnification from the distance to the subject and the focal length of the photographing lens;
The camera according to claim 1, wherein the correction value calculation means calculates the correction value according to a photometry result obtained by the photometry means and the photographing magnification.   The camera according to claim 6 or 7, wherein the correction value calculation means calculates a small value as the correction value when the photographing magnification is large. Furthermore, a metering means for metering the brightness of the subject,
Ranging means for measuring the distance to the subject;
The camera according to claim 1, wherein the correction value calculation means calculates the correction value according to a photometry result obtained by the photometry means and a distance measurement result obtained by the distance measurement means.   Furthermore, the photometric device includes photometric means for measuring the brightness of the subject, and the correction value calculating means calculates the correction value according to a photometric result obtained by the photometric means and a focal length of the photographing lens. Item 1. The camera according to Item 1.

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