JPS63303328A - Camera with built-in stroboscope - Google Patents

Abstract

PURPOSE:To take a picture satisfactorily by discriminating whether a built-in stroboscope or an externally fitted stroboscope is ready for photographing, and controlling a 1st or 2nd diaphragm value according to the state of the stroboscope. CONSTITUTION:A camera main body is provided with the built-in stroboscope, and the photographing or storage state is selected. The externally fitted stroboscope is mountable on the hot shoe of the camera main body. When photographing is done, either stroboscope is selected and light is emitted. At that time, the camera is provided with a control means, which discriminates as a 1st discriminating means whether the built-in stroboscope is ready for photographing. As a 2nd discriminating means to control means discriminates whether the externally fitted stroboscope is ready for photographing. When the built-in one is in a photographing state, the control means controls to the 1st diaphragm value; otherwise, the control means controls to the 2nd diaphragm value to take a picture. Thus both stroboscopes are made to have the same light arrival distance and the same photographing scope even if their guide numbers are different.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention has a built-in strobe in a camera body, and an external strobe can be attached via a hot shoe provided on the camera body. The built-in strobe and the external strobe are related to a camera that can selectively emit light from either the flash or the flash.

[Conventional technology]

In some conventional cameras, when using a strobe, the shutter speed and aperture value are determined by a mote called program fludge. This program flash mode 1 (lJ) determines the combination of shutter speed and aperture value based on shooting information such as the film sensitivity used and the brightness of the subject. Normally,
Such mode switching settings are made in conjunction with, for example, when the strobe is attached, when the strobe is powered on, and when the strobe is completely charged.

On the other hand, some recent cameras have a strobe built into the camera body and an accessory shoe provided on the camera body so that an external strobe can be attached to the accessory shoe. However, in such conventional systems, the camera usually does not determine whether the strobe used for shooting is an external strobe or a built-in strobe;
No matter which one is externally attached, the same program control is performed using the aforementioned program flash mode', and the same aperture value is obtained. FIG. 1O is a program diagram showing the control aperture value in the program flash mode of such a conventional camera. Here, the sensitivity of the film used and the brightness of the subject are used as the shooting information (however, Figure 10 shows the case where the subject brightness is constant), and the control aperture value is varied according to the sensitivity of the film used. .

In Figure 10, the thick solid line shows the relationship between the film sensitivity and the aperture value. Specifically, the film sensitivity is 150
If it is 100, the aperture value will be controlled to 5.6 for both the external strobe and the built-in strobe. In other words, when using an external strobe and a built-in strobe, the aperture value is always controlled to be the same. Therefore, for example,
~If the guide number of the robot is half that of the strobe light, the strobe light's reach will also be half that.

[Problems to be Solved by the Invention] As a series of examples: In conventional cameras, the external strobe and the built-in strobe are controlled by a uniform program without distinction, so the guide number of each strobe is There was a problem in that if the strobe light was different, the distance the strobe light could reach would be different accordingly.

Specifically, if the control aperture value for Program Franche mode is determined based on the assumption that an external strobe will be used,
-When using a built-in strobe with a small guide number in terms of 1ffi, the reach of the strobe light will be shorter than when using an external strobe with a large guide number, and the possible shooting range will be narrower. .

Therefore, the present invention makes it possible to ensure that the strobe light reaches a certain distance even when the built-in strobe of the camera is selectively used, and to minimize the difference between the range that can be photographed when using an external strobe. The purpose is to provide a camera that is easy to use for photographers.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention provides a first and second discrimination stage for determining whether to use a built-in strobe or an external strobe for photographing, and the first and second discrimination stages. When it is determined that the means is to perform the first shadow using the built-in strobe, the aperture value is set to the first aperture value, and when it is determined that the means is to be photographed using the external Zino strobe, the aperture value is set to be different from the first aperture value. and an aperture control means that performs photography by controlling the aperture value to a second aperture value, and the first and second discrimination means detect that the built-in strobe changes from the retracted state to the shooting state. is configured to determine.

[Effect]

By configuring the present invention as described above, when taking pictures using the built-in strobe, the external aperture value (second aperture value) is different from the aperture value (second aperture value) when taking pictures using the smartphone/robot. Since photography is carried out at an aperture value of 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 type type type type type type type type type type type type type type type type type type type type type type strobes can be used is the built-in strobe and the external strobe. In other words, the strobe light reach of the built-in camera and robot can be made comparable to that of the external camera and robot, so the possible photographic range will be different no matter which camera is used. Never.

Also, when the built-in flash changes from the retracted state to the shooting state, it is determined that the built-in flash is taking a picture.
Even if an external metrobe is attached in addition to the built-in strobe, the photographer can immediately recognize which strobe is being used to take a picture.

〔Example〕

FIG. 1 is a block diagram of an electric circuit in a camera showing an embodiment of the present invention. In FIG. 1, a central processing unit (hereinafter referred to as CPU) 10 that controls the operation of the camera includes a release switch 12, a half-press switch 13, a winding completion switch 15, a trailing curtain switch 16, and an input boat. A strobe up detection switch 43, a memory circuit 20 that stores photometry output, a shutter dial 1 that outputs information fHa regarding the set shutter speed, and a film sensitivity setting dial that outputs set film sensitivity information (hereinafter referred to as ISO information) b. 2 is connected. And as the output of CPUI O, IsO
Information C1 Information d regarding shooting sequence, exposure display, etc.
and information e regarding the control aperture value are output. Here, the half-press switch 13 is turned on by the first stroke of a release button (not shown), and the release switch 12 is turned on by the second stroke of the release button. The rso information from CPUI O is sent to arithmetic circuits 19 and 3.
However, the calculation circuits I9 and 33 are connected to a light receiving element (hereinafter referred to as SP for normal photometry) for performing TTL photometry during daylight photography.
D) 17 and a light receiving element (hereinafter referred to as TTL81i light SPD) 31 for performing TTL light control during strobe photography, through head amplifiers 18 and 32, A well-known logarithmic compression operation is performed. The signal from the normal photometry 5PD 17 is processed as described above and finally stored in the memory circuit 20.
Output to PIJlo. The strobe up detection switch 43 is turned on and off in conjunction with the amplifier down of the built-in strobe, which will be described later. The on/off signal of this strobe up detection switch/2ch 43 causes the CPU in the camera body to
O detects whether or not the built-in flash is in use. Decoder 21 receives a signal from CPULO and sends an activation signal for motor 23 to motor drive circuit 22 .

The motor performs operations such as closing the aperture and winding up the film. The decoder 21 also receives a signal from CPLJIO, and outputs AEi) 7; 1-ED 2 for small display.
4 and ready LED to indicate strobe charging completion
Drive 29. Furthermore, the decoder 21 also has a function of receiving a shutter activation signal from the CPU10 and sending the signal to the shutter magnet drive circuit 26. Note that when the decoder 21 converts an input signal into an output signal as described above,
It goes without saying that the signal should be appropriately decoded.

The shutter drive circuit 26 includes a leading curtain control magnet 27.
and a trailing curtain control magnet 28 are connected, and the magnets 27 and 28 are sequentially de-energized by the action of the drive circuit 26, and the shutter leading and trailing curtains (not shown) sequentially run.

The hot shoe 35 formed on the top of the camera body has
Four signal bins including the X contact 39 are installed. The hot shoe 35 itself is grounded, and the X contact 39 is connected via an X changeover switch 41 to an integration start switch (hereinafter referred to as Is switch) 40 that switches from the f terminal to the g terminal when the front curtain of the shutter completes travel. It is connected to the.

As will be described in detail later, the X selector switch 41 is used to transmit a synchronization signal (signal for switching the IS switch from the f terminal to the g terminal) to the external strobe I/Shoe 35, or to cause the built-in strobe to emit light. This switch switches whether or not to transmit the signal to the start terminal 5TART of the input port of the circuit 42, and similarly to the strobe up detection switch 43, it is turned on and off in conjunction with the built-in strobe amplifier down. When triggering a strobe, it is necessary to ground this X contact 39 or the start terminal STA RT.

An external strobe is attached to the hot shoe 35, and when the external strobe is powered on, a minute current flows through the ready terminal 36. When charging of the strobe is completed, a current larger than the minute current is applied to the ready terminal 36 of the external device.
It is structured so that it flows. The minute current flowing to the ready terminal 36 is detected by the CPU 10 via the dimming control circuit 34 and the decoder 21, and the CPU 10 issues a signal d to set the shutter to the strobe synchronization time, and the decoder 2
1, the strobe synchronization time is displayed on the AE exposure display LED 24. Also, a charging completion signal generated when charging of the strobe is completed is sent to the ready terminal 36 and the dimming control circuit 3.
4 to the decoder 21, and the decoder drives the ready LED 29.

A stop terminal 37 receives an external strobe light emission stop signal. This signal is emitted by an external strobe (or built-in strobe), and is sent to the 5PD31 for TTI-S circular light.
The output from the dimmer is integrated by the dimmer control circuit 34, and when the integrated value reaches the level, the dimmer control circuit 34 outputs the output. Incidentally, the integral operation of the dimming control circuit 34 is started when the above-mentioned Is switch 40 is switched from the f terminal to the g terminal.

The monitor terminal 38 is an external device attached to the hot shoe 35 that receives a signal from the strobe, and the external device identifies whether the strobe setting mode is external light control mode, manual mode, or TTL automatic light control mode. A signal is transmitted to the dimming control circuit 34.

The second part is a perspective view showing the external appearance of the camera of this embodiment.
A, and is rotatably supported by a hinge, which will be described later. Further, the hot shoe 35 described above is provided near the pentacover 5a. The center of rotation of the built-in strobe 6 is located near the eyepiece on the back side of the camera, and during normal shooting, the light emitting part (surface) 6a of the built-in strobe is located near the eyepiece.
As shown in the figure, the camera is pointing slightly downward toward the subject. This is the stored state of the built-in flash. Then, lift the front part of the strobe upward from the camera body and rotate the built-in strobe about 30 degrees around the hinge from the state shown in the figure, so that the light emitting part (surface) 6a will be in a position to face the subject. . This is the shooting state of the built-in flash.

FIGS. 3 and 4 show longitudinal sections of the built-in strobe 6 on the unwinding side and the unwinding side. 1. The strobe up detection switch notch (switch 43 in FIG. 1) is provided on the camera body 5 in FIG. 3 showing a cross section on the winding side. and a button 43c provided on the camera body 5 so as to be slidable downward.

The free end of the section 43b has a springing force upward in the figure, and the button 6043c is supported by the free end of this section 43b, and is biased so that one end of the button 43c always protrudes above the camera body 5. There is. One end of the button 43c is pressed against the bottom surface of the built-in strobe 6 when the built-in strobe is in the retracted state, and resists the spring force of the section 43b to move the section 43b to sections 4 and 3 a.
When the built-in flash is in the shooting state, the built-in strobe is retracted and the spring force of the section 43b causes the sections 43b and 4 to be separated from each other.
38 are in contact with each other. The strobe amplifier detection switch 43 shown in FIG. 1 opens and closes depending on whether or not the above-mentioned sections 43a and 43b come into contact with each other.

The camera body 5 is provided with a shaft portion 8 extending from the side surface of the pentacover 5a toward the winding side in a direction perpendicular to the paper surface of FIG.
b is provided. An inclined surface 6c and a groove 6d are provided on the inner peripheral surface of the cylindrical portion 6b. Further, the shaft portion 8 is provided with a groove portion 8a, in which a ball 7 and a spring 9 for pushing the ball 7 outward are arranged.

In Fig. 4, which shows a cross section of the built-in strobe on the rewind side,
An X switching switch provided on the camera body 5.

The switch 41 is composed of switch pieces 41a, 41b, and 41c having one end fixed to the camera body 5, and a button 41d provided on the camera body 5 so as to be slidable downward. The free end of the section 4lb has an upward force in the figure, and the button 41d is supported by the free end of this section 41b, so that one end of the button 41d always protrudes to one side of the camera body 5. energized. Here, 4.1a is the input port 5TART of the aforementioned built-in bus (-ropo circuit 42).
41b is connected to the g terminal connected to the IS switch 40, and 41c is connected to the X contact 39 of the hot shoe 35. Therefore, when the built-in strobe 6 is in the retracted state, one end of the button 41d is pushed against the bottom surface of the built-in strobe 6, resisting the spring force of the section 41b, and brings the section 41b into contact with the section IIc, so that the built-in strobe becomes in the shooting state. Then, the built-in strobe is retracted and the section 41. The spring force b separates the section 41b from 41c and brings it into contact with 41a.

The X selector switch 41 in FIG.
Switching occurs when b contacts either of the sections 41C and 418.

Further, the camera body 5 is provided with a shaft portion 9 extending from the side of the pentacover 5a toward the rewind side in a direction perpendicular to the plane of the paper in FIG. A cylindrical portion 6e is provided.

A hollow hole 9a is formed in the shaft portion 9, and a wiring lead 11 for connecting the electric circuit of the built-in strobe 6 and the electric circuit within the camera body passes through the hollow hole 9a.

The hinge that rotatably supports the built-in strobe 6 is constituted by the shaft portion 8.9 of the camera body shown in FIGS. 3 and 4, and the cylindrical portions 6b and 6e of the built-in strobe.

FIGS. 5 and 6 are sectional views corresponding to FIGS. 3 and 4, respectively, showing cross sections of the hinge part in the photographing state of the built-in strobe.

In FIG. 5, the built-in robot 6 has rotated approximately 30 degrees clockwise from the state shown in FIG.

The operation is accomplished by directly lifting the object-side tip of the strobe 6 by hand. By this operation, the cylindrical part 6b of the strobe 6 is
and the groove portion 6d rotates together with the strobe 6. This rotation causes the groove 6d to move into the ball 7 housed in the groove 9 of the shaft 8.
When facing the ball 7, the ball 7 urged by the spring 9 falls into the groove 6d and stops rotating. At the same time, the strobe lower surface 6r and the button 43C come out of contact. As a result, the button 43c protrudes from the camera surface 5a due to the spring force of the piece 43b itself. At the same time, the sections 43a and 43b are closed, and this switching sends a strobe-up signal to the CPU 10, which causes the CPU 10 to detect that the built-in strobe is in the photographing state.

In FIG. 6, as in FIG. 5, the rotation of the strobe 6 causes the cylindrical portion 6e to rotate with respect to the shaft portion 9.

When the button 41d and the lower surface 6g of the strobe come into contact with each other, the button 41d protrudes from the second surface 5b of the camera due to the biasing force of the section 41b. As a result, the state in which the sections 41b and 41c are in contact changes to the state in which the sections 41b and 41a are in contact. In this way, X switching is performed. in particular,
In the built-in strobe down state where the sections 41b and 410 are in contact, the synchro signal (Is switch 40 is switched from the f terminal to the g
The signal generated by switching to the terminal) is guided to the X contact 39 of the bot shoe 35. Also, sections 41a and 4
1. When the built-in strobe comes into contact with b, the synchronization signal is sent to the input port 5TAR of the built-in strobe circuit 42.
Guided by T.

Next, the operation of the above-mentioned camera will be explained based on the flowchart shown in FIG. First, a case in which normal AE photography is performed without using a built-in or external strobe will be described. Now, press the release button (not shown) halfway. The CPU 10 detects whether the half-press switch 13 is on or off at the start-up S1. If the half-press switch 13 is off, the process returns to the start again, but
If it is detected that it is turned on, the process advances to step s2.

Then, in step S2, signals from the shack dial 1, film sensitivity setting dial 2, etc. are input as photographic information input, and a photometry output that changes from moment to moment is inputted via the memory circuit 20. Note that, at this time, the memory circuit 2o is not yet performing a memory operation. Next, in step s3, it is determined whether the built-in strobe 6 is amplifying or not.

This is done by the CPU10 detecting whether the strobe amplifier detection switch 43 is on or off. Now, assuming that the strobe 6 is down and the strobe up detection switch 43 is off, CPUl0
determines this, proceeds to step S4, and selects the true shoe 3.
The external device attached to No. 5 determines whether or not the strobe's power switch is turned on. When the strobe power switch is turned on, a small current flows through the ready terminal 36.
A signal indicating that the strobe power switch is turned on is sent via the dimming control circuit 34 and decoder 21 to CPtJl.
The CPU 10 detects this signal and determines whether the external strobe is powered on or not. Now, if it is determined that the external strobe power switch is not turned on, the CPU 10 proceeds to step S5.

In step S5, one of the control program modes for normal photography without using a strobe (shutter priority, aperture priority, and AE mode that performs program exposure control) is selected.In step S6, the metering output and photography information obtained in step S2 are input. A proper exposure is calculated based on the proper exposure, and a signal regarding the shack speed, aperture value, etc. corresponding to this proper exposure is output to the decoder 21. For example, if program exposure control is selected in step S5, proper exposure is obtained. A combination of shutter speed and aperture value is output.

The decoder 21 receives this signal and outputs signals of the shutter speed and aperture value controlled to the AE display LED 24, and displays the shutter speed and aperture value. Then, the process advances to step S7. In this step S7, it is determined whether or not the release button has been pressed further. If the release button has not been pressed down the full stroke yet, the process returns to step S1. Then repeat this loop.

When detecting that the release button has been pushed down to its full stroke and the release switch 12 has been closed, the CPU 10 proceeds to step S8. In step S8, the CPU 10 outputs to the decoder 21 a motor drive signal and an excitation signal for exciting the magnets for controlling the leading and trailing shutter curtains. The decoder 21 transmits the drive signal to the motor drive circuit 22 and also transmits the excitation signal to the shutter magnet drive circuit 26. The motor drive circuit 22 causes the motor 23 to start rotating based on the drive signal. This causes the motor 23 to drive the diaphragm and perform a diaphragm operation. Further, the shutter magnet drive circuit 26 uses an excitation signal to excite the shutter leading and trailing curtain control magnets 27 and 28 to lock the shutter leading and trailing curtains together. The memory circuit 20 is provided with a delay concave path (not shown) so as to be activated a predetermined time after the start of the motor drive described above and to store the photometric output. The predetermined time is determined so that the memory circuit 20 performs the storage operation before the next step S9 starts. After the CPU 10 outputs a motor drive signal and a magnet excitation signal in step S8, the process proceeds to step S9. Then, CP[, JIO performs the same exposure calculation as in step S6 based on the photometric output etc. stored from memory circuit No. 20, and outputs to the decoder 21 a signal regarding the shack speed and aperture value for obtaining proper exposure. However, in this step, no exposure display is performed using the E display LED. The aperture control device 4 locks the aperture when the aperture of the aperture narrowed down by the motor 23 reaches a desired aperture value based on the exposure calculation output of the CPU10. The aforementioned motor 23 continues to rotate even after operating the diaphragm as described above, and then operates a mirror mechanism (not shown) to perform a mirror amplifying operation. CP tJ I O ill goes to step 810 after step S9. This step S
1. O is provided by a delay concave path (not shown) so as to start a predetermined time after the start of driving the motor described above. The predetermined time is when the mirror-up operation ends,
The start times of step SIO are determined to coincide. In step SIO, the CPU 10 outputs a first shutter curtain running signal for running the shack front curtain, and also outputs a motor stop signal. The decoder 21 transmits the signal to the shutter magnet drive circuit 26, and the shutter magnet drive circuit 26 releases the excitation of the front curtain control magnet 27, causing the shutter front curtain to run. Further, the decoder 21 transmits a motor stop signal to the motor drive circuit 22, and the motor drive circuit 22 stops the rotation of the motor 23. In step Sll, based on the shutter speed obtained by the exposure calculation in step S9, C1) Ulo outputs a second shutter curtain running signal for running the shutter trailing curtain after a predetermined exposure time has elapsed. The decoder 21 converts the signal into a shutter magnet.

1. The signal is transmitted to the drive circuit 26, and the shutter magnet drive circuit 26 releases the excitation of the trailing curtain control magnet 28, causing the shutter trailing curtain to run. When the trailing curtain switch 16 is turned on in step S12 and the completion of running of the shutter trailing curtain is detected, the CPU 10 outputs the motor drive signal again. The motor drive signal is then transmitted to the motor drive circuit 22 via the decoder 21, and the circuit 22 drives the motor 23 again. The motor 23 rotates to drive a film winding mechanism and a shutter charging mechanism (not shown) to wind the film and charge the shutter. When film winding and shutter charging are completed and the winding completion switch 15 is turned on, the CI) UIO detects this in step S13 and outputs a motor stop signal. The motor drive circuit 22 then stops the motor 23.

Second, attach the external strobe to the real shoe 35,
The camera operation when performing strobe photography using a robot will be explained. In this case, step S in FIG.
The operations from 1 to 3 are as described above. When step S4 is reached, the external CPU 10 attached to the hot shoe 35 determines whether or not the strobe power switch is turned on. That is, when the strobe power switch is turned on as described above, a minute current flows through the ready terminal 36, and a signal indicating that the strobe power switch is turned on is sent via the dimming control circuit 34 and decoder 21 to the CP.
The signal is transmitted to Ul0, and the CPU 10 detects this signal and determines whether the external strobe is powered on or not. If the CPU 10 determines that the power switch is turned on, the process advances to step S14. In step S14, a control mode for photographing using a strobe is selected. Then, the process advances to step S6. The step S6
Based on the IsO information and subject brightness information G out of the photographing information obtained in step S2, the CPU I O generates a signal regarding the control aperture value suitable for the strobe photography and a signal regarding the shutter speed (strobe synchronization time). Output. Thereafter, the same control as in steps S87 to S13 described above is performed. However, in this shooting mode using an external strobe, the aperture value and shutter speed to be controlled are those determined in step S6 (more specifically, step S9). Incidentally, in this step S6, the decoder 21
Needless to say, upon receiving the output of l0, the shutter speed and aperture value to be controlled are outputted to the AE display LED 24, and the shutter speed and aperture value at the time of strobe photography are displayed. Also, in step SIO, as mentioned above, the CPU
l0 outputs the first shutter curtain run signal to run the shutter front curtain, but when the shutter front curtain completes running, the IS switch 40 switches from the f terminal to the g terminal, so the X contact 39 is grounded, and when the power is turned on, the external devices that have already been charged are triggered by the strobes 1 to 39, and the strobes start emitting flash light. When a flash is generated, the reflected light from the subject enters the TT+- dimming light receiving element 31, and the integrated output reaches a predetermined value based on the photometric output and the TS○ information. When the dimming control circuit 34 detects this, a light emission stop signal is outputted from the dimming control circuit 34 to the stop terminal 37, and the external strobe light emission is stopped. Operations other than those described above are from step 87 to step S during AE photography described above.
It is exactly the same as 13.

Note that the above-mentioned strobe photography is based on photography information fHNs.

Since the aperture value and shutter speed are determined based on information (information and subject brightness), it goes without saying that this is the programmed flash mode mentioned at the beginning.

Third, camera operation when performing strobe photography using the built-in strobe will be explained. When the built-in strobe 6 is rotated from the retracted state shown in FIGS. 2 to 4 to the shooting state shown in FIGS. 5 and 6, the strobe up detection switch 43 is turned on, and the 41
The section changes from section c to section 41a. Then, the CPU 10 proceeds to step S1, step S2, and step S3 in the same manner as in each of the above-described photographing operations. In step S3, when the CPUI,0 detects that the switch 43 is on and determines that the built-in strobe 6 is up, the process advances to step s15. In step S15, a charging start signal is output to the built-in strobe circuit 42 to start charging the built-in strobe 6. Next, the process advances to step S16, and a control mode for photographing using the built-in strobe 6 is selected. Note that the CPU 10 selects the photographing mode using the built-in strobe 6 depending only on the ON signal of the switch 43, and the external strobe has no relation to whether or not the strobe is powered on. Then, proceeding to step S6, the CPU 10 generates a signal regarding the control aperture value suitable for built-in strobe photography and the shutter speed (strobe synchronization second) based on the ISO information and subject brightness information among the shooting information input obtained by the Stereo knob S2. outputs a signal regarding the time).

Thereafter, the same control ff1l as in steps 87 to S13 described above is performed. However, in the case of this built-in strobe as well as in the case of an external strobe, the aperture value and shutter speed to be controlled are those determined in step S6 (more specifically, step S9). This aperture value will be explained in some detail below. The aperture value is as described above <IS
The aperture value is determined by the ISO information and the subject brightness information, but for the sake of understanding, assuming that the subject brightness is constant, the aperture value depends only on the ISO information. Under these conditions, the diaphragm aperture that is controlled when photographing with the built-in flash is controlled to be larger than the aperture aperture when photographing with the external strobe. As described above, in this embodiment, the signal regarding the control aperture value output in step S6 (more specifically, step S9) is different when photographing is performed using the built-in strobe and when photographing is performed using the external strobe. Generally external L
The guide number of the J strobe is larger than the guide number of the built-in strobe, but in this example, as mentioned above, the aperture value controlled when shooting with the built-in strobe is the same as the aperture value controlled when shooting with the external strobe. This value is controlled so that the strobe light reach distance when shooting with the built-in strobe almost matches the one-shot light reach distance when shooting with an external strobe. It is something. In addition, when photographing with an external strobe, the CPU I O outputs the first shutter curtain run signal in step S10 to run the shutter front curtain, and when the IS switch 40 is
is switched from the f terminal to the g terminal, dropping the
Since it is switched from C to 413, the X contact 39 of the external strobe will not be grounded, and the external strobe will not emit light. Therefore, when shooting with the built-in flash, Is Suinoji 4 is
0 is switched from the "g" terminal to the "g" terminal, the input port (START) of the built-in strobe circuit 42 is grounded,
This happens every time a trigger signal is applied to the built-in strobe circuit 42. The built-in strobe 6 then starts emitting flash light.

Thereafter, the reflected light from the subject is received by the TTI light receiving element 31, and when the photometry output reaches a predetermined value, the light control circuit 34 outputs a light emission stop signal.
o Same as in the case of actual photography. In addition, when shooting with an external strobe, the light emission stop signal from the light control circuit 34 is guided to the stop terminal 37 of the pot shoe 35, but when shooting with a built-in strobe, this light emission stop signal is sent to the built-in strobe circuit. 42 input boat ST OI). The built-in strobe 6 stops emitting flash light by receiving this signal. Furthermore, in the case of photography using the built-in strobe, the shutter speed and aperture value to be controlled are displayed on the AE display LED 24 in step S6, as in the case of an external strobe. Operations other than those described above are from step 87 in normal AE photography and external strobe photography.
Since it is exactly the same as step S13, the explanation will be omitted.

Note that the above-mentioned built-in flash also uses shooting information (I
Since the aperture value and shutter speed are determined based on the SO information and the subject brightness information f[i), it goes without saying that this is the programmed flash mode mentioned at the beginning.

Next, when using an external strobe and when using a built-in strobe,
Each program flash mode will be further explained. FIG. 8 is a diagram showing two types of program flash modes in the embodiment described above. In the figure, the thick solid line indicates the program flash mode for the external strobe, and the thick broken line indicates the program flash mode for the built-in strobe. The aperture value shown in FIG. 8 corresponds to the control aperture value output from CPU10 to the aperture control device 4 in FIG. In this embodiment, as described above, the control aperture value during strobe photography is determined in consideration of the subject brightness information and ISO information, but in order to make it easier to understand, Fig. 8 shows the case where the subject brightness is constant. The aperture value is shown. According to FIG. 8, the aperture is controlled differently by two steps for the same film sensitivity in the external strobe mode and the built-in strobe mode. Therefore, even a built-in strobe with a small guide number can achieve a strobe light reach similar to that of an external strobe. In other words, even if the guide number of the built-in strobe is half that of the external strobe, the iris is controlled to open two stops when the built-in strobe is used, so the strobe light reaches the same distance.

Figure 9 shows another embodiment of the present invention. In the figure, the external strobe indicated by the thick solid line corresponds to the aperture value in strobe mode, while the built-in strobe is always controlled to a constant aperture value regardless of the film sensitivity used. be. Note that this is an example in which it is assumed that the subject brightness is also constant.

〔Effect of the invention〕

As described above, according to the present invention, since the aperture value to be controlled is different when taking pictures with the built-in strobe and when taking pictures with the external strobe, the guide numbers of the built-in strobe and the external strobe are different. Even if they are different, there will be no major difference in the reach distance of the strobe light, making it possible to realize a camera that is easy to use. Also, when the built-in flash changes from the retracted state to the shooting state, it is determined that the built-in flash is being used to take a picture, so even if an external flash is attached in addition to the built-in flash, you can shoot with either flash. This is convenient because the photographer can immediately recognize what is being done.

In the example, the external strobe and the built-in strobe were selected as an alternative, and the aperture value etc. to be controlled was changed depending on the selected strobe, but the external strobe and the built-in strobe can be used simultaneously. It may be configured as follows. in this case,
Needless to say, a selection means for selecting simultaneous use and a detection means for detecting the state are required.

[Brief explanation of the drawing]

Fig. 1 is an electric circuit block diagram of a camera showing an embodiment of the present invention, Fig. 2 is a perspective view showing the external appearance of the camera in the above embodiment, and Figs. 3 to 6 are built-in strobe lights of the camera in the above embodiment. FIG. 7 is a flowchart showing the operation of the above embodiment, FIG. 8 is a program diagram when using a strobe in the above embodiment, FIG. 9 is another program diagram, and FIG. 10 is a conventional program diagram. Program diagram when using a strobe. [Explanation of symbols of main parts] 4...Aperture control device 5...Camera 6...Built-in strobe 10...CPU 35...Hot shoe 41...X selection switch

Claims (1)

[Scope of Claims] The camera is equipped with a built-in strobe that takes a photographing state in which the light-emitting surface faces the subject and a stored state in which the light-emitting surface does not face the subject. In a camera that is attachable and capable of selectively emitting light from either the built-in strobe or the external strobe, a first determining means for determining whether the built-in strobe is in a shooting state or in a retracted state. and a second determining means for determining whether or not the external strobe is in a photographing state; and when the first determining means determines that the built-in strobe is in a photographing state, the aperture is set to a first setting. Photographing is performed by controlling an aperture value of , the first determining means determines that the built-in strobe is in a retracted state, and the second determining means enables photographing with the external strobe. When the aperture is determined, the aperture is changed to a second aperture value different from the first aperture value
and an aperture control means for controlling the aperture value to take pictures,
A camera with a built-in strobe, characterized in that the photographable range remains the same even when flash photography is performed with either the built-in strobe or the external strobe.