JP2000338576A - Flash control system and camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate an exposure control, and to reduce a red eye phenomenon and the occurrence of the shadow of a subject without making the device large in size in a flash control system composed of a camera main body and a remotely controllable external flash. SOLUTION: The aperture scale corresponding to the flashing quantity of the external flash 100 for obtaining a part of the proper exposure value is calculated. By flashing the built-in flash 16 only twice, information corresponding to the aperture scale and a flashing timing are transmitted to the external flash. The external flash 100 is flashed at the light quantity corresponding to the aperture scale. In order to expose, the built-in flash 16 is flashed at the light quantity to obtain all the remaining quantity of the proper exposure value. By flashing both of the external flash 100 and the built-in flash 16, the proper exposure value is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a flash control system including a camera body and an external flash which can be remotely operated by a signal transmitted from the camera body.

[0002]

2. Description of the Related Art Conventionally, in a single-lens reflex camera, a trigger signal for starting light emission and a stop signal for stopping light emission are transmitted from the camera body to an external flash wirelessly separated from the camera body. A known flash control system is known. These trigger signal and stop signal are optical signals generated by the light emission of the built-in flash mounted on the single-lens reflex camera, and the light emission of the external flash is controlled by being detected by the external flash.

[0003]

In such a flash control system, a stop signal cannot be detected when the external flash is emitting light, so that the external flash is intermittently emitted, and the external flash stops emitting light. During this time, a stop signal is detected. For this reason, a circuit for intermittently emitting the external flash is required, which complicates the circuit configuration and increases the size of the device. Further, when the emission of the external flash is stopped, an optical signal must be transmitted from the built-in flash, which makes it difficult to control communication between the camera body and the external flash.

Further, if the external flash is used away from the photographing optical axis of the single-lens reflex camera, the shadow of the subject appears in the photographed photograph, whereas the external flash is close to the photographing optical axis of the single-lens reflex camera. When used in state,
There is a problem that a red-eye phenomenon occurs.

The present invention relates to a flash control system comprising an SLR camera body and an externally operable external flash. In a flash control system, exposure control is easily performed without increasing the size of the apparatus, and red-eye effect and shadow of a subject are reduced. The aim is to reduce the occurrence.

[0006]

SUMMARY OF THE INVENTION A flash control system according to the present invention is a flash control system for remotely photographing an external flash separated from a camera by an optical signal from the camera. Light source, light emission amount setting means for setting the light emission amount of the camera light emission source for obtaining a part of the proper exposure amount, and information corresponding to the light emission amount of the external flash for obtaining the remaining all of the proper exposure amount. An external flash information calculating unit, an optical signal generating unit that generates an optical signal based on information corresponding to the amount of light emission of the external flash and the light emission timing of the external flash, and light emission of the camera light emission source according to the light emission timing. Starting the camera, and causing the camera light source to emit light at the set light emission amount of the camera light source. The flash unit includes a flash light source, an optical signal detection unit that detects an optical signal from the camera, and a light source that controls the light amount of the flash light source according to information corresponding to the light amount of the external flash transmitted by the light signal. It is characterized by comprising a quantity control means and a light emission timing control means for causing a flash light emission source to emit light at an emission timing of an external flash determined by an optical signal.

Preferably, the optical signal generating means generates an optical signal by causing the camera light source to emit light a plurality of times, and of the plurality of times of light emission, a light emission interval between a first light emission and a subsequent second light emission. Corresponds to the flash output of the external flash,
The second light emission is performed at the light emission timing. Alternatively, preferably, the light signal generating means generates a light signal by causing the camera light emitting source to emit light twice, and makes the light emission interval of the two light emission correspond to the light emission amount of the external flash, and makes the second light emission the external flash. At the light emission timing. In these cases, preferably, the camera has detection means for detecting light emitted from the camera light emitting source, and integrating means for detecting an integrated value corresponding to the total light amount of the light, and light emission of the camera light emitting source has started. Thereafter, when the integrated value reaches a reference value corresponding to the light emission amount of the camera light source, the camera light source light emission unit stops the light emission of the camera light source, and the external flash emits an optical signal corresponding to the light emission amount of the external flash. When the light signal detection means detects light emission at the light emission timing, the light emission timing control means causes the flash light emission source to emit light, and the light emission amount of the flash light emission source is determined by the light emission interval. When the light emission amount corresponding to the light emission interval measured by the measurement unit is reached, the light emission amount control unit stops the light emission of the flash light emission source.

Preferably, the light emission amount setting means sets the light emission amount of the camera light source to obtain one third of the proper exposure amount,
The external flash information calculation means calculates information corresponding to the light emission amount of the external flash for obtaining ２ of the appropriate exposure amount. Also preferably, the camera has timing setting means for setting the emission timing of the external flash based on information corresponding to the emission amount of the camera emission source. Still more preferably, the camera light-emitting source light-emitting means causes the camera light-emitting source to emit light after a lapse of a predetermined time from the light emission timing.
Preferably, the information corresponding to the light emission amount of the external flash is information corresponding to the aperture value.

According to the present invention, there is provided a camera body, a camera light source, a light amount setting means for setting a light amount of the camera light source for obtaining a part of the proper exposure amount, A remaining light emission amount information calculating means for calculating information corresponding to the remaining light emission amount to obtain all of the remaining light, and generating an optical signal based on the information corresponding to the remaining light emission amount and the light emission timing, and outputting the light signal outside the camera body An optical signal transmitting means for transmitting light to a light emitting source provided, and a camera light emitting means for starting light emission of the camera light emitting source in accordance with a light emission timing and emitting the camera light emitting light at a set light emission amount of the camera light emitting source And characterized in that:

[0010] Preferably, the light emission amount of the camera light emission source is for obtaining 1/3 of the appropriate light emission amount. Also, preferably, the camera light source light emitting means starts light emission of the camera light source after a predetermined time has elapsed from the light emission timing. Still more preferably, the information corresponding to the remaining light emission amount is information corresponding to the aperture value.

[0011]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a flash control system according to the present embodiment. The flash control system includes a camera 10 and an external flash 100.

The camera 10 is a single-lens reflex camera and has a built-in flash 16. This built-in flash 16 is used for flash photography, and is used for external flash 10
It also functions as a control signal source for controlling light emission of 0. A lens barrel 23 holding a lens 24 is attached to the front face 10b of the camera 10.

When the camera 10 is viewed from the front, the camera 10
The release button 12 is provided on the left shoulder of the power button 13. The power switch 13 and the flash mode changeover switch 25 are disposed on the opposite side of the release button 12. The release button 12 is a self-back switch that can be pressed in two stages. When the release button 12 is half-pressed, preparation for photographing such as photometry is performed, and when the release button 12 is fully pressed, photographing is performed. The power switch 13 is a transfer switch for switching power on / off. The flash changeover switch 25 is a self-back switch for selecting the built-in flash 16 and the external flash 100 or the like. Each time the flash changeover switch 25 is pressed once, the flash off mode, the built-in flash mode, and the external flash mode are sequentially switched. Can be A camera-side connector 14 to which the external flash 100 can be attached is provided above the release button 12.

The external flash 100 has a connector section 150 fitted to the camera-side connector 14 and can be used in a clip-on mode attached to the camera 10 or a wireless mode separated from the camera 10. The external flash 100 is placed on the upper surface 100a of the external flash 100.
Mode selection switch 152 and the external flash 100
Power switch 154 is provided. The mode selection switch 152 of the external flash 100 is a self-back switch. Each time the mode selection switch 152 is pressed once, the wireless mode and the clip-on mode are alternately selected. A light receiving unit 155 is provided on the front surface 100b of the external flash 100.

In the camera 10, when the external flash mode is set by the flash mode changeover switch 25 and the wireless mode is set by the mode selection switch 152 in the external flash 100, both the external flash 100 and the built-in flash 16 emit light. The subject A is photographed. In this case, camera 1
When the release button 12 of “0” is half-pressed, the camera 10
Then, photometry is performed. Thereafter, when the release button 12 is fully pressed, the built-in flash 16 of the camera 10 emits light with a relatively low light amount. The light signal by this light emission is for controlling the light emission of the external flash 100, is reflected by the subject A, and is detected by the light receiving unit 155 of the external flash 100. With this light signal, information corresponding to the light emission amount of the external flash 100 and the light emission timing of the external flash 100 are transmitted from the camera 10 to the external flash 100. And external flash 10
0 is emitted with the light emission amount and light emission timing according to the optical signal, and further, the built-in flash 16 is caused to emit light with the light emission amount for obtaining a part of the appropriate exposure amount. At this time, the light emission amount of the external flash 100 is for obtaining the rest of the proper exposure amount, and the light emission of both the external flash 100 and the built-in flash 16 causes the subject A to emit the light amount for obtaining the proper exposure amount. And the photographing is performed.

The electrical configuration of the camera 10 will be described with reference to FIGS. The camera 10 is supplied with power from the battery 70 and becomes operable when the power is switched on by the power switch 13. The entire camera 10 is a CPU 40
, And processes such as light emission control of the built-in flash 16 and exposure calculation are executed.

The photographing optical system 47 has an aperture, which is driven by a lens drive circuit 49. The shutter is configured as a focal plane shutter including a front curtain shutter 45a and a rear curtain shutter 45b, and its driving is controlled by a shutter driving circuit 45. Front curtain shutter 4
The shutter switch 33 can be turned on / off in conjunction with 5a.

The photometric circuit 22 has a photometric sensor, and measures the luminance of the subject A based on a detection signal of the photometric sensor.
The AF detection circuit 27 detects the amount of focus shift at the time of photographing, and the driving of the AF drive circuit 43 is controlled according to the detected amount of focus shift. The AF motor M4 is driven by the AF drive circuit 43, and a focus lens (not shown) is moved, thereby performing focus adjustment. The display unit 30 is configured by an LCD or the like, and displays information such as a photographing mode and the number of photographed films.

The film feeding section 42 drives a film feeding motor M1 to feed the film. The film feed detecting section 28 detects whether or not the film feed has been completed. The back cover switch 36 can be turned on / off in conjunction with opening and closing of the back cover of the camera 10. The rewind switch 34 is for performing forcible rewind, and can be turned on / off by an operator. When the photographing is completed or the back cover switch 36 or the rewind switch 34 is turned on, the film feed motor M is
1 is driven, and the film is fed.

The built-in flash 16 includes a booster circuit 16a, a light-emitting capacitor (main capacitor) 16b, a light-emitting tube 16c such as a Xe tube, a light-emitting circuit 16d, and a charging voltage detecting circuit 16e. In the booster circuit 16a, the battery 7
The power supply voltage of the main capacitor 1
A voltage for charging 6b is generated. Light emitting circuit 16
An IGBT is used for d, and the start and stop of light emission of the arc tube 16c are controlled by turning on / off the IGBT by the CPU 40, and the light emission time of the arc tube 16c can be controlled. The charging voltage detection circuit 16e detects the charging voltage of the main capacitor 16b.

When the built-in flash mode or the external flash mode is selected by the flash changeover switch 11 connected to the CPU 40, the built-in flash 16 operates in accordance with a command from the CPU 40 to increase the voltage of the booster circuit 16a.
To charge the main capacitor 16b or to emit light from the arc tube 16c by the light emitting circuit 16d, and the main capacitor 16b detected by the charging voltage detecting circuit 16e.
The charging voltage b is output to the CPU 40 as charging voltage data.

The TTL light receiving section 44a is arranged so as to be able to receive the reflected light from the film surface in the SLR camera. Light incident through the photographing lens is reflected by the film surface inside the SLR camera, and the reflected light is detected by the TTL light receiving unit 44a, and is integrated as an electric charge by the integration circuit 44b.
Is output to In the integrating circuit 44b, the TTL light receiving section 44a
Are integrated, and an integrated voltage corresponding to the total amount of light detected by the TTL light receiving unit 44a is output to the CPU 40 as integrated voltage data. On the other hand, in the setting circuit 44c, a reference voltage corresponding to the amount of light to be emitted from the built-in flash 16 is determined based on the film sensitivity data and the like detected by the DX code detector 26, and this reference voltage is sent to the CPU 40 as reference voltage data. Will be entered. The CPU 40 performs TTL dimming by comparing the input integrated voltage data with the reference voltage data, and controls the light emission of the built-in flash 16.

The TTL dimming control by the CPU 40 will be described in detail. In the built-in flash 16, the IGBT of the light emitting circuit 16 d is turned on in response to a command from the CPU 40, thereby causing the light emitting tube 16 c to emit light. Accordingly, the integration circuit 44b is operated by the CPU 40. The light emitted from the built-in flash 16 is reflected by the subject and enters the SLR camera via the taking lens. This light is reflected by the film surface in the SLR camera,
It is detected by the TTL light receiving unit 44a. In the CPU 40, the integrated voltage data from the integration circuit 44b and the setting circuit 44c
Is compared with the reference voltage data. When the integrated voltage data reaches the reference voltage data, the IGBT of the light emitting circuit 16d is turned off by a command from the CPU 40, and the light emitting tube 16c is turned off.
Light emission is stopped. In this way, the light emission amount of the built-in flash 16 is controlled by the TTL light control.

The DX code detector 26 detects the DX code of the film cartridge, and uses the film sensitivity information read from the DX code as C sensitivity data.
Transferred to PU40.

The CPU 40 has a self mode switch 35
When the self-mode is set by the self-mode switch 35, a self-lamp 66 indicating that a self-timer is operating at the time of photographing is turned on, and self-mode photographing is performed.

When the release button 12 is half-pressed, that is, when the photometry switch is turned on, the AF driving circuit 44
By this, the AF motor M4 is driven, and the focus of the photographing optical system 47 is adjusted. In the photometric circuit 22, the luminance of the subject is measured based on the detection signal of the photometric sensor, and the luminance of the subject is output to the CPU 40 as luminance data.
Further, film sensitivity data is input from the DX code detection unit 26 to the CPU 40. The CPU 40 calculates exposure conditions based on the film sensitivity data and the luminance data.
That is, when performing automatic exposure control, an appropriate aperture value and shutter speed are obtained from film sensitivity data and luminance data, and when an appropriate aperture value is set by the photographer, the film sensitivity data, luminance data and setting The shutter speed is calculated from the determined appropriate aperture value.

When the release button 12 is fully pressed, that is, when the release switch is turned on, when performing automatic exposure control, the aperture of the aperture is set according to the appropriate aperture value. When the proper aperture value is set by the photographer, the aperture of the aperture has already been set according to the first aperture value. In a state where the aperture of the aperture is set according to the appropriate aperture value, shooting is performed according to the mode setting state by the flash mode changeover switch 25.

When the built-in flash mode is set by depressing the flash mode changeover switch 25 and only the built-in flash 16 emits light, the front curtain shutter 45a runs under the control of the shutter drive circuit 45 to open the shutter. Thereafter, the built-in flash 16 is caused to emit light. After the emission of the built-in flash 16 ends, the rear curtain shutter 45b runs under the control of the shutter drive circuit 45, and the shutter is closed. Therefore, the proper exposure amount is obtained by the emission of the built-in flash 16, and the subject A is photographed.

On the other hand, when the external flash mode is set by depressing the flash changeover switch 11, the front curtain shutter 45a runs, and when the shutter is opened, the built-in flash 16 turns the external flash 1
The light is emitted twice for communication with 00. The interval between the two flashes corresponds to an aperture value calculated based on the appropriate aperture value, and the aperture value corresponds to the flash amount of the external flash 100 for obtaining ／ of the appropriate exposure amount. .
The information corresponding to the light emission amount of the external flash 100 and the light emission timing are transmitted to the external flash 100 based on the light signal by the two light emission. When the second flash of the built-in flash 16 ends, the external flash 10
Light is emitted at a light amount corresponding to the information corresponding to the light emission amount of the external flash 100 to which 0 has been transmitted. After the emission of the external flash 100 ends, the built-in flash 16
Is emitted to obtain 1/3 of the proper exposure.
The subject A is illuminated by the light emission of both the external flash 100 and the built-in flash 16, and thereafter, the rear curtain shutter 45b runs and the shutter is closed. Thus, the light emission of the external flash 100 and the built-in flash 1
The subject A is illuminated and photographed with a light amount that can obtain an appropriate exposure amount by combining the light emission of No. 6 with the light emission of No. 6.

The electrical configuration of the external flash 100 will be described with reference to FIGS. 1, 3 and 4. The external flash 100 includes a booster circuit G1, a light emitting capacitor (main capacitor) 109, a charging voltage detecting circuit G2,
The light emitting circuit G3 includes a CPU block G4 and a light receiving circuit G5 shown in FIG.
b, c, d, and e are terminals a, b, c, and
It is connected to d and e. CP in the CPU block G4
U123 and its peripheral elements are provided, and the external flash 100 is controlled by the CPU block G4. CP
The power switch 154 and the mode selection switch 152 are connected to the port Pint of the U123.
When 4 is turned on, the external flash 100 can perform a flash operation. The power supply terminal Vdd of the CPU 123 includes:
Schottky diode 120 and regulator 12
2 is connected to the battery 106 via the
From 06, a constant voltage is applied. An EEPROM 124 is connected to the port Pa of the CPU 123.
In the EPROM 124, data such as the amount of dimming correction of the external flash is recorded. Port P of CPU 123
A display element group 126 and a flash external terminal 125 are connected to b and Pc, respectively.

Ports P1, P2 and ports P4 to P6 of the CPU 123 are output ports, and the output level is switched to "1" (high) or "0" (low) under the control of the CPU 123. Ports Pint, P
3, P7 and P8 are input ports, which are externally set to "1".
A (high) or “0” (low) level signal is input. Port Pda is a D / A conversion output port, and port Pad is an A / D conversion input port.

A battery 106, an oscillating transistor 101, a transistor 102, an oscillating transformer 10
The booster circuit G1 boosts the voltage of the battery 106.

When the port P2 of the CPU 123 becomes "1", the transistor 102 is turned on and the transistor 10
The oscillation transistor 101 is turned on by the emitter current of No. 2. Thereby, the primary winding P of the oscillation transformer 104
, A voltage is generated in the secondary winding S. This voltage is supplied to the main capacitor 109 via the diode 105.
And the main capacitor 109 is charged. The oscillation transistor 101 is temporarily turned off due to the magnetic saturation of the oscillation transformer 104. Therefore, the main capacitor 109 is charged while the oscillation transistor 101 is repeatedly turned on / off. The oscillation transformer 104 is provided with an auxiliary winding F, and a voltage generated in the auxiliary winding F is supplied to the regulator 12
2 is applied. As a result, even if a voltage drop of the battery occurs during charging of the main capacitor 109, the CPU 123
Of the power supply terminal Vdd is prevented from changing.

The charging voltage detecting circuit G2 detects the charging voltage of the main capacitor 109,
7, 108. While the port P2 of the CPU 123 is “1” and the main capacitor 109 is being charged, the dividing resistors 107 and 108
9. Split resistor 107, 1
08, the charging voltage of the main capacitor 109 is divided, and the divided voltage is input to the port Pad of the CPU 123 as analog charging voltage data. At this port Pad, analog voltage data is converted into digital charging voltage data.

The light emitting circuit G3 includes a xenon (Xe) tube 115
And controls the discharge of the Xe tube 115. The light emitting circuit G3 includes a trigger coil 111, a capacitor 11
2, 113, a diode 116, an IGBT 117, etc. are provided.
The start and stop of the fifteen light emission are controlled. When the charging voltage of the main capacitor 109 becomes, for example, 330 V and the charging is completed, when the port P1 of the CPU 123 becomes "1", the IGBT 117 is turned on. At this time, a high voltage is generated in the winding S of the trigger coil 111 due to resonance between the capacitor 112 and the winding P of the trigger coil 111, and the Xe tube 115 is triggered. At the same time, the potential of the cathode of the diode 116 becomes “0”, so that the voltage of the capacitor 113 and the charging voltage of the main capacitor 109 are applied to the Xe tube 115. The voltage of the capacitor 113 is equal to the charging voltage of the main capacitor 109. Therefore, the Xe tube 115 is applied with a voltage twice the charging voltage of the main capacitor 109, and emits light stably. When the port P1 of the CPU 123 becomes “0”, the IGBT 117 is turned off, and the light emission of the Xe tube 115 is stopped.

The light receiving circuit G5 corresponds to the light receiving section 155 shown in FIG. 1, and in the wireless mode, an optical signal from the built-in flash 16 of the camera 10 (reflected light from a subject).
And a light emission amount of the external flash 100, and includes a phototransistor 138.

When the port P4 of the CPU 123 is set to "1" in a state where the charging of the main capacitor 109 of the external flash 100 is completed, the analog switch 130 is turned on, the light receiving circuit G5 is supplied with electric power, and becomes operable. . When the port P5 of the CPU 123 becomes “1” and the port P6 of the CPU 123 becomes “0”, the analog switch 131 connected to the port P5 is turned on, and the analog switch 132 connected to the port P6 is turned off. Further, analog switches 133 and 134 are connected to a port P6 of the CPU 123 via an inverter 135, and a signal “1” is input to a control terminal C of the analog switches 133 and 134, and the analog switches 133 and 134 are turned on. Is done. In the state of the analog switches 131 to 134, the collector of the phototransistor 138 is connected to the contact between the capacitor 140 and the resistor 139, the capacitor 137 is connected via the analog switch 133, and the capacitor 136 is connected via the analog switch 131. Each is completely discharged. In such a state, the light receiving circuit G5 can detect light.

When the built-in flash 16 of the camera 10 emits light while the light receiving circuit G5 is capable of detecting light,
The optical signal from the built-in flash 16 is reflected by the subject and detected by the phototransistor 138, and a collector current is generated. This collector current causes the resistor 139
And a capacitor 140 and a resistor 1 forming a differentiating circuit.
Current flows through the transistors 14 and 142, and as a result, the transistor 14
A voltage is applied to the base of No. 3. When this voltage exceeds the threshold voltage, that is, when the light amount of the optical signal detected by the phototransistor 138 exceeds a predetermined amount, the transistor 143 turns on. As a result, the port P7 of the CPU 123 connected to the collector of the transistor 143 changes from “0” to “1”. Due to this change of the port P7, the CPU 123
It is detected whether is emitting light.

When the port P6 of the CPU 123 becomes "1", the analog switches 133 and 134 are turned off and the analog switch 132 is turned on. As a result, the phototransistor 138 is connected to the capacitor 137. A capacitor 136 is connected to and disconnected from the capacitor 137 in accordance with the output level of the port P5 of the CPU 123. That is, when the port P5 is “1”, the capacitor 136 is connected in parallel to the capacitor 137, and when the port P5 is “0”, the capacitor 136 is not connected to the capacitor 137. The capacitance ratio between the capacitors 137 and 136 is 1:31. These capacitors 137 and 136 form an integration circuit.
Switching can be performed by connecting and disconnecting to 37. Hereinafter, the case where the port P5 is “0” and the capacitor 136 is not connected in parallel will be described.

The light detected by the phototransistor 138 is converted into a charge by the capacitor 13 forming an integrating circuit.
7 and integrated. The voltage (integrated voltage) of the capacitor 137 corresponds to the integrated amount of light (total light amount) detected by the phototransistor 138 and is input to the comparator 145. The comparator 145 compares the integrated voltage with a reference voltage input from the port Pda of the CPU 123, and outputs the comparison result to the port P8 of the CPU 123. This change in port P8 causes CP
In U123, it is detected whether the received light amount has reached a predetermined light amount.

The external flash 1 configured as described above
When 00 is set to the wireless mode and the camera 10 is set to the external flash mode, the external flash 100 and the camera 10 communicate with each other by emitting light from the built-in flash 16. Next, this communication will be described.

FIG. 5 shows a camera 10 and an external flash 100.
6 is a timing chart showing the communication of FIG. The built-in flash 16 of the camera 10 is used to transmit an aperture value and a light emission timing corresponding to the light emission amount of the external flash 100 to the camera.
Light emission is performed twice. The second flash is the external flash 10
0 and a trigger for causing the built-in flash 16 to emit light. The time interval T between the first light emission and the second light emission
_AV corresponds to the aperture value.

At time T1, the built-in flash 16 of the camera 10 starts the first light emission for communication. The light signal due to this light emission is reflected by the subject A, enters the light receiving section 155 of the external flash 100, and is received by the light receiving circuit G
5 is detected by the phototransistor 138. Therefore, a collector current starts flowing in the phototransistor 138 (reference S7), and the transistor 143 is turned on. As a result, the port P7 of the CPU 123 becomes “0”.
It changes from (code S13) to “1” (code S14). CP
In U123, when the port P7 changes to "1", the time until the port P7 changes from "0" to "1" again is measured.

From time T1 to time T2, the built-in flash 16 of the camera 10 continues to emit light. During this time, the collector current of the phototransistor 138 of the external flash 100 is flowing, and the port P7 of the CPU 123 maintains “1”.

At time T2, when the internal flash 16 of the camera 10 stops emitting light, the external flash 100
The collector current of the phototransistor 138 is “0”.
(Reference S8), and the transistor 143 is turned off. As a result, the port P7 of the CPU 123 becomes “0” (reference S15).

When the time interval T _AV elapses from the time T1 and reaches the time T3, the built-in flash 16 of the camera 10 starts the second light emission for communication. The light signal due to this light emission is detected by the phototransistor 138 of the external flash 100 similarly to the first light emission, and the collector current of the phototransistor 138 starts to flow (reference S9).
As a result, the transistor 143 is turned on, and the CPU 12
The port P7 of "3" again changes from "0" (reference S15) to "1"
(Sign S16).

In the CPU 123, when the port P7 changes to "1" for the second time, the time measurement is completed, and from the first change of the port P7 (time T1) to the second change of the port P7 (time T3). time interval T _AV of is detected. The Xe of the external flash 100 is determined based on the time interval T _AV.
The amount of light to be emitted from the tube 115 (target amount of light) is determined. This target light emission amount is for obtaining ／ of the appropriate exposure amount, and a voltage level corresponding to the target light emission amount is output from the port Pda of the CPU 123 to the comparator 145 as a reference voltage. In the CPU 123, the port P
When 7 changes to “1” for the second time, port P1 becomes “1”.
(Reference S19), the IGBT 117 is turned on, and the Xe tube 115 of the external flash 100 emits light (reference S2).
2) is started. At this time, the focal plane shutter of the camera 10 is completely opened as described later.

In the timing chart of FIG. 5, after the port P7 changes to "1" for the second time, ie, the camera 1
After the internal flash 16 of 0 emits the second light signal,
After a predetermined time TD ₁ has elapsed (time T5), it is shown as light emission of the Xe tube 115 of the external flash 100 is started, but the time TD ₁ is a time negligible in practice It is provided for convenience in the notation of the timing chart. Time That is, in order to avoid some of the waveform on the timing chart are too close to each other, only TD ₁ is provided as the time negligible, time T4 and T5 which are substantially matched to one another Becomes

At time T5, port P6 of CPU 123
Becomes “1”, the Xe tube 11 of the external flash 100
The emitted light 5 is reflected by the subject A and detected by the phototransistor 138 of the external flash 100. The detected light is accumulated as a charge in the capacitor 137 or the capacitors 136 and 137, and the integrated voltage of the capacitor 137 or the capacitors 136 and 137 is input to the comparator 145. This integrated voltage corresponds to the total amount of light detected by the phototransistor 138.

In the comparator 145, the capacitor 13
7 or the integrated voltage of capacitors 136 and 137
This is compared with the reference voltage output from the port Pda of 123. When the integrated voltage becomes larger than the reference voltage, the output level of the comparator 145 changes. That is, the Xe tube 1
When the light emission amount of No. 15 reaches the target light emission amount, the comparator 1
The output level of 45 becomes “1”. This output level is C
It is input to port P8 of PU123, and port P8
Changes from "0" to "1" (time T6). In response to this change, in the CPU 123, the port P1 is set to “0”, the IGBT 117 is turned off, and the light emission of the Xe tube 115 is stopped. In this way, the external flash 10
0 is emitted with a light emission amount based on the information corresponding to the aperture value. When the external flash 100 stops emitting light, C
The port P6 of the PU 123 becomes “0” and the capacitor 1
36 and 137 are discharged, and the integrating circuit is deactivated.

[0051] When the second predetermined time TD ₂ from the emission of the built-in flash 16 has elapsed (time T7), is caused to emit light at a light quantity for the built-in flash 16 gets 1/3 of the appropriate exposure amount again. Incidentally, the maximum emission time of the external flash 100 for a predetermined time TD _2, for example, is set as 5 ms, thus completely open row under the emission of light substantially focal plane shutter of the built-in flash 16 following the emission of the external flash 100 Will be

As described above, during communication, the built-in flash 16 of the camera 10 emits light twice. As a result, the information corresponding to the aperture value and the light emission timing are transmitted to the external flash 100. The aperture value corresponds to the light emission amount of the external flash 100 for obtaining ２ of the appropriate exposure amount,
The light emission amount of the external flash 100 is controlled according to the information corresponding to the aperture value, that is, the time interval T _AV . The second flash of the built-in flash 16 is
It becomes a trigger signal of light emission of 0. On the other hand, built-in flash 1
After the emission of the external flash is completed, the reference numeral 6 emits light at an emission amount for obtaining 1/3 of the appropriate exposure amount. Therefore, an appropriate exposure amount can be obtained by the light emission of both the external flash 100 and the built-in flash 16, and photographing with high-precision exposure is performed.

The operation of the camera 10 will be described with reference to FIG. FIG. 6 is a flowchart of a main routine showing the operation of the camera 10. This main routine is executed when the power switch 113 is turned on.

In step S1201, the CPU 40
, Each RAM, and each register are initialized.
In step S <b> 1202, the charge request flag f is set to “1” indicating that the main capacitor of the built-in flash 16 is charged in preparation for photographing the built-in flash 16. In step S1203, the rewind switch 3
It is determined whether or not 4 has been turned on. Rewind switch 3
When the switch 4 is turned on, the forced rewinding process routine of step S1204 is executed, and the film is forcibly rewound until the film feeding detecting unit 28 detects the end of the film feeding. If it is determined in step S1203 that the rewind switch 34 is not turned on, then in step S1205, the back cover switch 36
It is determined whether or not has changed. When it is determined that the back cover switch 36 has changed, a back cover opening / closing processing routine is executed in step S1206. In this back cover opening / closing processing routine, when the back cover of the camera 10 is closed, the film feeding unit 42 When cueing of the first frame of the film is performed and the back cover of the camera 10 is opened, a film counter for counting the number of films is set to “0”.

On the other hand, if it is determined in step S1205 that the back cover switch 36 has not changed, it is determined in step S1207 whether the release button 12 has been half-pressed, that is, whether the photometry switch has been turned on. Is done. When it is determined that the photometry switch has been turned on, in step S1208, a photographing processing routine to be described later is executed, and photographing is performed.

If it is determined in step S1207 that the photometry switch has not been turned on, the process proceeds to step S1.
In 209, it is determined whether or not the charge request flag f for charging the main capacitor of the built-in flash 16 is "1". When the charge request flag f is not “1”, the process of step S1211 is performed. On the other hand, when the charge request flag f is “1”, the process proceeds to step S121.
At 0, a main charging process routine described later is executed. The main charging process routine is performed when the power is turned on by the power switch 13 or after photographing using the built-in flash 16.
The main capacitor of the built-in flash 16 is charged in order to make it possible to emit light. When this main charging processing routine is completed, step S12 of the main routine is executed.
Eleven processes are executed.

In step S1211, the power switch 1
It is determined whether 3 has been turned off. Power switch 13
Is determined to be turned off, a sleep mode with low power consumption is set in step S1212. On the other hand, if it is determined in step S1211 that the power switch 13 has not been turned off, the process of step S1203 is executed again.

Each of the steps S1204, S1206,
When the processing in S1208 ends, the processing in step S1203 is executed again.

Step S120 of the above main routine
The photographing processing routine performed in step 8 will be described with reference to FIGS.

In step S1241, it is determined whether the flash off mode has been set. If the flash-off mode is not set, step S
At 1242, a photographing charging process routine described later is executed, and it is detected whether or not the built-in flash 16 is in a state capable of emitting light. When light emission is impossible, charging is performed.

In step S1243, it is determined whether or not charging has been completed so that built-in flash 16 can emit light. If charging is completed, step S12
The processing in step 46 is executed, and if not, the photographing processing routine ends.

If it is determined in step S1241 that the flash-off mode has been set, then in step S1246, an AF processing routine is executed to execute AF processing.
The focus shift amount is detected by the detection circuit 27, and the focus lens is driven by the AF drive circuit 43 in accordance with the shift amount.
And is placed at the in-focus position. Step S
In 1247, a photometric processing routine is performed, and the luminance of the subject is measured by the photometric circuit 22 and read as luminance data. In step S1248, an exposure calculation processing routine to be described later is executed. In the exposure calculation processing routine, a shutter speed is calculated based on the photometry result by the photometry circuit 22 and the set aperture value. In the automatic exposure control mode, the aperture value is calculated together with the shutter speed from the photometric result.

In step S1249, the release button 1 is pressed.
It is determined whether or not 2 is half-pressed, that is, whether or not the photometric switch is turned on. When it is determined that the photometry switch is not turned on, it means that the photographing has been stopped, and the photographing processing routine ends. On the other hand, when it is determined that the photometry switch is turned on, it is determined in step S1251 whether the release button 12 has been fully pressed, that is, whether the release switch has been turned on. If the release switch is not turned on, the processing from step S1247 to step S1251 is executed until the release switch is turned on or the photometry switch is turned off.

On the other hand, if it is determined in step S1251 that the release switch has been turned on, the process proceeds to step S1.
At 252, it is determined whether the self switch 35 has been turned on. When the self switch 35 has not been turned on, the process of step S1254 is executed. On the other hand, when the self-switch 35 is turned on, in step S1253, as a self-waiting process, a self-time of 10 seconds is secured, and a self-lamp 66 for informing the subject of the exposure timing is turned on and off. Is performed.

Steps S1254 and S12
In 55, only when the automatic exposure control mode is set, the lens aperture setting processing routine is executed, the lens aperture is driven by the aperture drive circuit 49, and the lens aperture is controlled according to the calculated aperture value.

In step S1256, an exposure control processing routine described later is executed, and the shutter is driven and exposed based on the calculated aperture value and shutter speed. Upon completion of the exposure, in step S1257,
A winding process routine is executed, and the film is wound by one frame. At this time, if the winding of the film is not completed within the specified time, it is determined in step S1258 that the film has been completed, the automatic rewinding of the film is performed by the automatic rewinding processing routine of step S1259, and the photographing processing routine ends. . On the other hand, if it is determined in step S1257 that the winding of one frame has been completed and it is determined in step S1258 that the film has not ended, the shooting processing routine ends.

FIG. 9 shows a step S121 of the main routine.
9 is a flowchart of a main charging process routine performed at 0.

In step S1281, a timer with a time-up time of 10 seconds for measuring the charging time of the built-in flash 16 is started. Step S128
At 2, the charging signal of the built-in flash 16 is turned on, and charging of the built-in flash 16 is started. Step S128
At 3, the charging voltage check processing routine is executed, and the charging voltage of the main capacitor of the built-in flash 16 is detected. If it is determined in step S1284 that the charging voltage is equal to or higher than 330 V, or if it is determined in step S1285 that the timer has expired and the charging time has passed 10 seconds, the charging request flag f is determined in step S1287. Is set to "0", the charging of the main capacitor of the built-in flash 16 is terminated in step S1288, and the main charging process routine ends.

On the other hand, in step S1284, it is determined that the charging voltage is smaller than 330 V, and
If it is determined in 1285 that the timer has not expired, it is determined in step S1286 whether any one switch has been operated. When it is determined that any one of the switches has been operated, the charging of the main capacitor of the built-in flash 16 is temporarily terminated in step S1288, and the main charging process routine ends. In this case, the charge request flag f is still set to "1", so that when the process according to the switch operation is completed, the charging of the main capacitor of the built-in flash 16 is continued in the main charging process routine again. On the other hand, if it is determined in step S1286 that none of the switches has been operated,
The process of 1283 is executed again, and the charging is continued.

FIG. 10 shows a step S1 of the photographing processing routine.
It is a flowchart of the photography charge processing routine performed in 242. In this photographing charge processing routine, when the built-in flash 16 needs to emit light in the built-in flash mode or the external flash mode, it is determined whether or not the charging voltage is at a level at which light emission is possible. When the charging voltage is not at a level at which the built-in flash 16 can emit light, the main capacitor of the built-in flash 16 is charged.

More specifically, first, in step S1301, an appropriate charging mark is blinked on the display unit 30 to notify the photographer that the built-in flash 16 is being charged.

In step S1302, time-up time 1 for measuring the charging time of built-in flash 16
The 0 second timer starts. In step S1303, charging of the main capacitor of the built-in flash 16 is started.

In step S1304, a charge voltage check processing routine is executed, and the charge voltage of the main capacitor of the built-in flash 16 is detected as charge voltage data. It is determined whether or not the charging voltage data detected in step S1307 is 270 V or more. If the charging voltage data is 270 V or more, the charging of the main capacitor of the built-in flash 16 is terminated in step S1308, and then, in step S1309, the display of the charging mark on the display unit 30 changes from blinking display to continuous display, Thus, the photographer is notified that the charging has been normally performed.

On the other hand, when it is determined in step S1307 that the detected charging voltage data is smaller than 270 V, it is determined in step S1311 whether the timer has expired. When the timer has not expired, it is determined in step S1312 whether the photometry switch has been turned off, that is, whether the release button 12 has been half-pressed. If the half-press of the release button 12 has not been released, the charging of the main capacitor of the built-in flash 16 is continued, and the process of step S1304 is executed again. On the other hand, in step S1312, the release button 12
When it is determined that the half-press has been released, step S1
At 313, the charge request flag f is set to "1" so as to perform charging for the next shooting. Then, the charging is terminated in step S1314, and then, in step S1315, the display of the charging mark on the display unit 30 changes from blinking display to non-display, thereby informing the photographer that charging is abnormal. .

If it is determined in step S1311 that the timer has expired, the process proceeds to step S1311.
In 14, the charging of the main capacitor of the built-in flash 16 is terminated, and the photographing charge processing routine ends.
In this case, since the charging has not been completed normally, the photographing is not permitted in the photographing processing routine.

FIGS. 11 and 12 show an exposure calculation processing routine performed in step S1248 of the photographing processing routine. In this exposure calculation processing routine, the shutter speed T _V and the aperture value A _V are obtained based on luminance data, film sensitivity data, and the like, which are photometric results of the photometric circuit 22.

In step S1331, it is determined whether the automatic exposure control mode has been set. When the automatic exposure control mode is not set, the aperture value is set by the photographer, so that the aperture priority processing is performed in steps S1332 to S1336.
On the other hand, when the automatic exposure control mode is set, the aperture value is automatically set in steps S1338 to S1342.

[0078] In step S1332, the aperture value A _V set by the photographer is read in step S133
3 and the aperture data A _V and the brightness data B
_V and the film sensitivity data S _V from the shutter speed T _V
Is calculated by the equation (1). _{T V = B V + S V} -A V ··· (1)

In step S1334, it is determined whether the flash off mode has been set. When the flash-off mode is set, the exposure calculation processing routine ends. Meanwhile when the flash-off mode is determined not to be set, that is, when the built-in flash mode or the external flash mode is set, in step S1335, whether or not the shutter speed T _V is greater than the flash synchronization speed T _VS is Is determined. Flash tuning speed T _VS is built-in flash 16
Is the fastest shutter speed at which the shutter can be fully opened during the light emission of, and is a limit value. If the shutter speed T _V is greater than the flash synchronization speed T _VS, in step S 1336, the shutter speed T _V is set in the flash synchronization speed T _VS, exposure calculation processing routine ends. In step S1335, the shutter speed T _V
There equal to or less than the flash synchronization speed T _VS, as the exposure calculation processing routine ends.

When the automatic exposure control mode is set
In step S1338, the luminance data B_VAnd
Film sensitivity data S_VAperture value A based on_VAnd shut
Speed T_VIs required. In step S1339
To determine whether the flash off mode is set.
Is determined. Check that flash off mode is set.
When it is determined, the exposure calculation processing routine ends. on the other hand
It was determined that the flash off mode was not set
In step S1340, the shutter speed T_VBut
Flash tuning speed T_VSIt is determined whether it is greater than
Shutter speed T_VIs the flash synchronization speed T_VSBigger
Then, in step S1341, the shutter speed T_V
Is the flash tuning speed T_VSIs changed to Step S1
At 342, the shutter speed T_VAlong with the change of aperture
Value A_VIs reset, and the exposure calculation processing routine ends.
You. On the other hand, in step S1340, the shutter
Speed T _VIs the flash synchronization speed T_VSIf
The exposure calculation processing routine ends as it is.

FIGS. 13 to 15 are flowcharts of an exposure control processing routine performed in step S1256 of the photographing processing routine. In this exposure control processing routine, the shutter is driven based on the shutter speed T _V , the flash emission is controlled based on the aperture value A _V , and photographing is performed.

[0082] In step S1401 the shutter speed T _V
Then, the control interval TTV between the front curtain and the rear curtain of the shutter is obtained. In step S1402, the timer 1 for controlling the shutter drive is set to the control interval TTV between the front curtain and the rear curtain, and starts. In step S1403, the front curtain shutter 45a is caused to run, whereby the shutter is opened. In step S1404, it is determined whether the flash off mode has been set. If the flash-off mode has been set, the process in step S1423 is performed. If the flash-off mode has not been set, the process waits in step S1405 until the shutter switch 33 is turned on. When it is determined that the shutter switch 33 has been turned on, that is, when the shutter has been fully opened, step S
At 1406, it is determined whether the external flash mode is set. When it is determined that the external flash mode is set, that is, when both the external flash 100 and the built-in flash 16 emit light at the time of exposure, the process of step S1407 is executed.
On the other hand, when it is determined that the external flash mode is not set, that is, when the built-in flash mode is set and only the built-in flash 16 emits light, the process of step S1416 is executed.

In the external flash mode, step S14
At 07, the first flash of the built-in flash 16 is started for communication, and after waiting for 100 μsec at step S1408, the flash of the built-in flash 16 is stopped at step S1409. Step S1
In 410, the conversion aperture A to obtain 2/3 of the proper exposure amount corresponding to the aperture value A _V that is set or calculated
_V is calculated by equation (2). ^{_{A V = A V * -log (}} 3/2) - (S V -5) ≒ A V * -0.585- (S V -5) ··· (2) where, S _V is film speed data , And A _V ^* is the aperture value A _V , which is denoted by the symbol ^* for explanation. The converted aperture value A _V calculated in this way corresponds to ／ of the total light amount for obtaining a proper exposure. A time interval T _AV corresponding to the converted aperture value A _V is obtained. FIG. 16 shows a correspondence table between the conversion aperture value A _V and the time interval T _AV . This correspondence table is C
It is created in a memory (not shown) provided in the PU 40, and the time interval T _AV is obtained by referring to this correspondence table. After waiting for the calculated time interval T _AV , in step S1411, the second flash of the built-in flash 16 for communication is started. Step S
After waiting for 100 μsec for 1412, the emission of the built-in flash 16 is stopped in step S1413. Note that the aperture value A _V and the converted aperture value A _V are APE
An X value, the aperture value A _V is used to define the aperture size, the conversion aperture A _V is used to control the light emission amount of the external flash 100.

The above steps S1407 to S1407
At 1413, the built-in flash 16 fires only twice
Time interval T between two light emission_AVIs the conversion aperture value A
_VTransmitted to the external flash 100 as information corresponding to
It is. Conversion aperture value A_VIs the amount of light emitted from the external flash 100
And the external flash 100 has a time interval T _AV
Is emitted with the amount of light emission based on The second flash is out
It becomes a trigger signal for light emission of the flash unit. Conversion aperture
Value A_VExternal flash for information communication time corresponding to
The flash of the shutter 100 is delayed from the shutter fully open timing, but twice
Time interval T of light emission_AVIs set within 2ms
So it doesn't matter. In addition, the external flash 100
With a long light emission time of 5 msec and a time interval of two light emission of 2 msec
The shutter opening time is 7 msec.
Yes, flash tuning speed can be set to 1/125
You.

In step S1414, after the external flash 100 has finished emitting light, the built-in flash 16 is fired for exposure, so that the process waits for a time, for example, 5 msec, when the emission of the external flash 100 is surely finished. The camera 10 has a built-in flash 16 for exposure.
When the built-in flash 16 emits light, an integrated voltage corresponding to the amount of reflected light from the subject of the built-in flash 16 is detected. TTL dimming is performed to control Therefore, step S1
At 415, a reference voltage is determined based on the film speed data. More specifically, a voltage for obtaining an appropriate exposure amount corresponding to the film sensitivity data is predetermined.
A voltage for obtaining an appropriate exposure amount is obtained from the film sensitivity data. This voltage corresponds to the amount of light for obtaining an appropriate exposure amount, and 1/3 of this voltage is determined as a reference voltage. By determining the reference voltage in this manner, the amount of light to be emitted from the built-in flash 16 is 1/1 / the appropriate exposure amount.
This is the amount of light for obtaining 3. When the reference voltage is determined in step S1415, the process of step S1417 is performed.

On the other hand, in the built-in flash mode, in step S1416, a voltage for obtaining proper exposure is obtained from film sensitivity data, and this voltage is determined as a reference voltage.

In step S1417, the timer 2 for measuring the time for performing TTL dimming is set to 5 ms and started. In step S1418, the built-in flash 1
Light emission of No. 6 is started. In step S1419 to step S1420, when the timer 2 times out or when the integrated voltage exceeds the reference voltage in the TTL light control and the built-in flash 16 emits the light amount to be fired, in step S1421, the built-in flash 16
Light emission is stopped. By causing the built-in flash to emit light as described above, one-third of the proper exposure is obtained in the external flash mode, and the proper exposure is obtained in the built-in flash mode.

In step S1422, the charge request flag f is set to "1" to charge the built-in flash 16 in preparation for the next photographing, and the flow waits in step S1423 until the timer 1 times out. When the timer 1 times out, the rear curtain shutter 45b is caused to run in step S1424. As a result, the shutter is closed, and the exposure control processing routine ends.

As described above, the light emission of the built-in flash 16 of the camera 10 is controlled. In the external flash mode, the built-in flash 16 emits light only twice. This 2
The time interval T _AV of one light emission corresponds to the aperture value A _V ,
The second light emission serves as a trigger signal for light emission of the external flash 100. That is, the aperture value A
_The information corresponding to _V and the light emission timing are transmitted. Information corresponding to the aperture value A _V transmitted to the external flash 100 corresponds to the light amount to obtain 2/3 of the proper exposure amount. On the other hand, the amount of light to be emitted from the built-in flash 16 is determined as the amount of light for obtaining 1/3 of the appropriate exposure amount. As will be described later, the light emission amount of the external flash 100 is controlled based on information corresponding to the aperture value A _V , and the external flash 100 emits light at a light emission amount for obtaining を 得 of the appropriate exposure amount. When the light emission of the built-in flash 16 and the external flash 100 is controlled in this manner, an appropriate exposure amount is obtained by the light emission of both the external flash 100 and the built-in flash 16. The light emission timing of the external flash 100 may be set so that the light emission of both the external flash 100 and the built-in flash 16 is completed while the shutter is open.

The operation control of the external flash 100 will be described below. 17 and 18 show the external flash 100.
This is the main routine that controls the operation of. This main routine is executed when the power switch 154 is turned on or when the battery 106 is loaded.

In step S101, each port of the CPU 123 is initialized. Ports P1, P2, P4, P
5, P6 and Pda are output ports, and ports Pint and Pda
3, P7 and P8 are input ports. Port Pad is A /
This is a D conversion function port. Each of the ports Pa, Pb, and Pc includes a plurality of input / output ports, and is set to perform a predetermined function.

In step S102, the EEPROM 12
From 4 the data such as the flash dimming correction amount
Is input to In step S103, a charge completion flag Fcharge indicating completion of charging of the main capacitor 109 of the external flash 100 is set to "0". In the charging completion flag Fcharge, “0” indicates a state in which charging is not completed.

In step S104, a 125 ms timer interrupt is permitted. That is, an interrupt of the 125 ms timer interrupt process is generated every 125 ms. In the 125 ms timer interrupt process, the charging voltage of the main capacitor 109 is detected as charging voltage data, and it is checked whether the charging is completed. The details of the 125 ms timer interrupt process will be described later. When it is determined in step S105 that the charging completion flag Fcharge is not “1”, that is, when the charging of the main capacitor 109 is not completed, or when it is determined in step S106 that the wireless mode is not set, That is, when the clip-on mode is set, in step S109, the below-described P7 interrupt processing for communication with the built-in flash 16 of the camera 10 and emission of the external flash 100 is prohibited. Then, in step S110, the CPU 123
Is set to "0", and the analog switch 130 for connecting the power supply to the light receiving circuit G5 is turned off. In step S110, the ports P5 and P6 are set to “0”, the driving of the phototransistor 138 is stopped, and the port Pad is set to “0”.
Detection of the charging voltage of the main capacitor 109 is stopped. In step S111, the external flash 100
The clip-on flash process when using in the clip-on state is performed. In the clip-on-flash processing, the external flash 100 is controlled by the camera 10 through conventionally known data communication. Step S
When the process of step S111 ends, the process of step S112 is executed.

On the other hand, in steps S105 to S106, the charge completion flag Fcharge is “1”, and the charging of the main capacitor 109 has been completed.
When the wireless mode is set, step S1
At 07, the port P4 of the CPU 123 is set to "1", the analog switch 130 for connecting the power supply to the light receiving circuit G5 is turned on, and power is supplied to the light receiving circuit G5. Further, the port P5 is set to “1”, the analog switch 131 is turned on, and the capacitor 136 is in a chargeable state. The port P6 is set to “0”, the analog switch 132 is turned off, and the analog switch 13
3, 134 are turned on. Thus, ports P4, P4
By setting 5, P6, reception of an optical signal in the wireless mode and dimming of the flash can be performed. In step S108, the below-described P7 interrupt processing for performing communication with the built-in flash 16 of the camera 10 and emission of the external flash 100 is permitted.

In step S112, it is determined whether power switch 154 has been turned off. If the power switch 154 remains on, the process proceeds to step S10.
5 is executed again, and when it is determined that the power switch 154 is turned off, in step S113,
All interrupt processing of the CPU 123 is prohibited. In step S114, each port of the CPU 123 is initialized again, and in step S115, Pint interrupt processing is permitted. In this Pint interrupt processing, the power switch 15
When 4 is turned on, the main routine is executed. Then, in step S116, the CPU 123 is set to the sleep mode in which the power consumption becomes substantially “0”.

FIG. 19 is a flowchart showing the timer interrupt processing. This timer interrupt processing is shown in FIG.
When the interruption is permitted in step S104 of the main routine shown in FIG.

In step S120, the interruption of the 125 ms timer interruption processing is prohibited. Therefore, while the 125 ms timer interrupt process is being executed, no further 125 ms timer interrupt process is executed. In step S121, the port P2 of the CPU 123 is set to “1”, and the main capacitor 10
The charging of 9 is started. In step S122, A / D conversion of the port Pad is performed, and the main capacitor 10
Charge voltage of 9 is digital charge voltage data (A / D value)
Is detected as In step S123, it is determined whether the charging voltage data is higher than the maximum charging voltage Vmax (for example, 330 V) read from the EEPROM 124 in step S102. When the charging voltage data is higher than the maximum charging voltage Vmax,
When the charging of No. 9 is completed, in step S124, the port P2 of the CPU 123 is set to “0”, the charging is terminated, and the process of step S128 is executed.

On the other hand, when it is determined in step S123 that the charging voltage data is equal to or lower than the maximum charging voltage Vmax, it is determined in step S125 whether the charging voltage data is higher than the minimum voltage Vmin at which the external flash 100 can emit light. . Charge voltage data is minimum voltage Vmin
When it is determined that the value is larger than the predetermined value, the process of step S128 is performed.

In step S128, since the charging has been completed, the charging completion flag Fcharge is set to "1".
In step S129, the completion of charging is displayed on the display element group 126, and the process of step S130 is executed.

On the other hand, in step S125, the charging voltage data is set to the minimum voltage V at which the external flash 100 can emit light.
When it is determined that it is equal to or less than min, that is, when the charging is not completed, in step S126, the charging completion flag Fcharge is set to “0”, and in step S127.
In the display, it is displayed on the display element group 126 that charging has not been completed yet, and the process of step S130 is executed.

In step S130, the interruption of the 125 ms timer interruption process is permitted, and the
The timer interrupt processing ends.

The P7 interrupt processing will be described with reference to FIGS. 5, 20, and 21. This P7 interrupt processing is permitted in step S108 in the main routine shown in FIG. When the phototransistor 138 of the external flash 100 detects an optical signal generated by the light emission of the internal flash 16 and the transistor 143 is turned on and the port P7 becomes "1", the P7 interrupt processing is executed.

In step S140, all interrupt processing is prohibited. In step S141, the timer 1 starts. This timer 1 is different from the timer for 125 ms interruption. In the step S142, the process waits until the port P7 becomes “0”,
Becomes "0" (time T2), it is determined in step S143 whether or not the port P7 is "1". When the port P7 is determined not "1", the maximum time period of the timer 1 at step S145 is determined by the control range of the aperture value A _V Tmax
(For example, 2.0 msec). If the elapsed time of the timer 1 has not reached the maximum time Tmax, the process of step S143 is executed again.
On the other hand, when the elapsed time of the timer 1 has reached the maximum time Tmax in step S145, the process of step S157 is executed.

On the other hand, when it is determined in step S143 that the port P7 is "1" (time T3), in step S144, the elapsed time of the timer 1 is detected as the time interval T _AV , Interval T _AV
Corresponds to the aperture value A _V. In step S146, it is determined whether or not the time interval T _AV is shorter than a minimum time Tmin (for example, 1.0 msec) determined by the control range of the aperture value A _V. When the time interval T _AV is smaller than the minimum time Tmin, the process of step S157 is performed.

On the other hand, in step S146, the time interval
T_AVIs longer than the minimum time Tmin, step S14
7, the photoelectric sensitivity of the phototransistor 143 is measured.
Fluctuations and capacitance variations of the capacitors 136 and 137
To compensate, the time interval T _AVIs EEPROM124
The dimming correction amount α read out is added. Step S1
At 48, the corrected time interval T_AVBased on
Pressure level V_AVAnd the level of the port P5 are determined. Voltage
Level V_AVIs CP as a reference voltage of the comparator 145.
Output from port Pda of U, port P5 is determined
Set to level. Note that the corrected time interval is shown in FIG.
T_AVAnd voltage level V_AVAnd the level of port P5
Here is a table. Time interval T_AVIs greater than "1.5"
The port P5 is set to “1” and the analog switch 13
1 turns on the capacitor 136 and the capacitor.
137 are connected in parallel. This allows external flash
For detecting the integrated voltage corresponding to the light emission amount of the
The range of the integration circuit is switched.

In step S149, the flow waits until the port P7 becomes "0". When the port P7 becomes "0" (time T4), in step S150, the timer 1 restarts from "0". In step S151, the port P1 is set to “1”, the IGBT 117 is turned on, a trigger for causing the Xe tube 115 of the external flash 100 to emit light is applied, and the emission of the Xe tube 115 is started (time T5).

At step S152, port P6 is set to "1". This allows the analog switch 13
3 and 134 are turned off, the analog switch 132 is turned on, and the integrating circuit using the capacitors 136 and 137 detects the total amount of light emitted from the Xe tube 115 as an integrated voltage. More specifically, the light emission of the Xe tube 115 is detected by the phototransistor 138 after being reflected by the subject,
The electric charge corresponding to the light is stored in the capacitor 137 or in the parallel capacitors 137 and 136. Here, the capacity of the capacitor 136 is set to 31 times the capacity of the capacitor 137. The port P5 is set to a level corresponding to the time interval T _AV , and connection / disconnection of the capacitor 136 is determined according to the level of the port P5. When the port P5 is "0", the capacitor 13
6 is not connected, and when the port P5 is “1”, the capacitor 136 is connected in parallel with the capacitor 137. Thereby, the range of the integration circuit by the capacitors 136 and 137 is switched, and it is possible to cope with the case where the integration voltage becomes large. In FIG. 16, the time interval T _AV is 1.5
, When the port P5 is “0” and when the port P5
Is "1", the voltage level V _AV is 32 times the value, which corresponds to the ratio of the capacitance of the capacitor 137 to the parallel capacitance of the capacitors 137 and 136.

Capacitor 137 or capacitor 13
The integrated voltages of the parallel capacitors 6 and 137 are input to the comparator 145, and are compared with a voltage level V _AV which is a reference voltage.

In step S153, it is determined whether the port P8 is "1". Level of the port P8 is the output level of the comparator 145, when the port P8 is "0", a state in which the integrated voltage has not reached the reference voltage V _AV, i.e. the total amount of light the target light emission amount emitted in the Xe tube 115 a state that does not reach the, when the port P8 is "1", the state in which the integrated voltage reaches the reference voltage V _AV, i.e. a state in which the emitted total light amount has reached the target amount of light emission of the Xe tube 115.

When it is determined in step S153 that the port P8 is "1", the process of step S155 is executed. On the other hand, when it is determined in step S153 that the port P8 is not “1”, in step S154, the elapsed time of the timer 1 is Xe.
It is determined whether or not it is longer than the maximum light emission time Tflash by the tube 115. Elapsed time of timer 1 is maximum emission time T
If it is smaller than flash, the process from step S153 to step S154 is repeated. If it is determined in step S154 that the elapsed time of the timer 1 is equal to or longer than the maximum light emission time Tflash, the process of step S155 is executed.

When the integrated voltage reaches the reference voltage V _AV in step S153, or when the light emission time of the Xe tube 115 exceeds the maximum light emission time in step S154, the port P1 is set to “0” in step S155.
Is set, the IGBT 117 is turned off, and the Xe tube 115
Is stopped (time T6). Here, when the integrated voltage has reached the reference voltage V _AV , the amount of light emitted from the Xe tube 115 corresponds to the aperture value A _V transmitted from the camera 10, and is 光 量 of the amount of light required to obtain a proper exposure. Has been reached. Therefore, the total light amount emitted from the Xe tube 115 has reached the target light emission amount.

In step S156, the charge completion flag Fcharge is set to "0" to request recharging. In step S157, the timer 1 is stopped, and in step S158, the ports P4 and P5 are set to "1".
Then, the port P6 is set to "0", and each port of the CPU 123 is returned to the state before performing the P7 interrupt processing. In step S159, all interrupt processing is permitted, and the P7 interrupt processing ends.

As described above, in the external flash 100, the light emission amount and the light emission timing of the Xe tube 115 are controlled based on the light signal by the light emission of the built-in flash 16 of the camera 10.

According to the above embodiment, the camera 10 as a single-lens reflex camera and the wireless external flash 10
Communication is made by causing the built-in flash 16 of the camera 10 to emit light only twice. Information corresponding to the light emission amount of the external flash is transmitted by the time interval between the two flashes of the built-in flash 16, and the external flash 100 is caused to emit light with the light emission amount based on this information. Further, the second emission of the built-in flash 16 becomes a trigger signal for emission of the external flash 100, and the emission timing of the external flash 100 is controlled. Thus built-in flash 1
Exposure condition information can be easily obtained by camera 1
0 to the external flash 100, whereby the external flash 100 can easily control the light emission timing and light emission amount. Therefore, there is no need to provide a special circuit for communication, and the device is not enlarged. In addition, after the external flash 100 emits light, the built-in flash 16 is made to emit light. Since the light emission of the external flash 100 and the light emission of the built-in flash 16 are not performed simultaneously, the light emission of each flash is detected independently. Therefore, the amount of light emitted from each flash is accurately obtained, and the amount of light emitted from both the external flash 100 and the built-in flash 16 is controlled with high accuracy, and appropriate exposure is performed.

Further, at the time of exposure, both the external flash 100 and the built-in flash 16 emit light, so that the shadow of the subject caused by each flash is weakened mutually.
This can reduce the shadow of the subject on the photograph. Further, the external flash 100 can be used in a state away from the photographing optical axis, and the red-eye phenomenon is prevented.

In this embodiment, an aperture value that is easy to handle in calculation or control and has high versatility is calculated as a parameter indicating the light emission amount of the external flash, and information corresponding to the aperture value is transmitted to the external flash. It is also possible to use another parameter as a parameter indicating the amount of light emitted from the external flash. In the present embodiment, the camera 10
Although the light emission for communication with the external flash 100 and the light emission for exposure of the built-in flash 16 are performed independently, the light emission for exposure can also be used as the light emission for communication. .

[0117]

As described above, according to the present invention, in a flash control system including a camera body and an externally operable external flash, exposure control can be easily performed without increasing the size of the apparatus. In addition, the occurrence of the red-eye phenomenon and the shadow of the subject is reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a flash control system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a camera.

FIG. 3 is a block diagram showing a part of an external flash.

FIG. 4 is a block diagram showing a part of an external flash.

FIG. 5 is a timing chart showing communication between a camera and an external flash.

FIG. 6 is a flowchart of a main routine showing an operation of the camera.

FIG. 7 is a flowchart of a photographing processing routine (first half);
It is.

FIG. 8 is a flowchart of a photographing processing routine (second half);
It is.

FIG. 9 is a flowchart of a main charging process routine.

FIG. 10 is a flowchart of a photographing charge processing routine.

FIG. 11 is a flowchart (first half) of an exposure calculation processing routine.

FIG. 12 is a flowchart (second half) of an exposure calculation processing routine.

FIG. 13 is a flowchart (first part) of an exposure control processing routine.

FIG. 14 is a flowchart (second part) of an exposure control processing routine.

FIG. 15 is a flowchart (third part) of an exposure control processing routine.

FIG. 16 is a correspondence table of a light emission time interval with respect to an aperture value, a reference voltage of a comparator, and an output level of a port P5 of a CPU.

FIG. 17 is a flowchart (first half) of a main routine showing an operation of an external flash.

FIG. 18 is a flowchart (second half) of a main routine showing the operation of the external flash.

FIG. 19 is a flowchart of a 125 ms timer interrupt process.

FIG. 20 is a flowchart (first half) of P7 interrupt processing;

FIG. 21 is a flowchart (second half) of P7 interrupt processing;

[Explanation of symbols]

 10 Camera 16 Built-in flash (camera light source) 100 External flash 115 Xe tube (flash light source)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03B 15/03 G03B 15/03 GF term (Reference) 2H002 CD00 CD07 CD08 CD09 CD11 CD13 FB22 FB24 FB38 FB84 GA31 GA61 GA72 GA75 HA14 JA02 2H053 AA03 AA06 AA09 AB01 AD00 AD03 AD12 AD21 AD23 BA51 BA54 BA72 BA73 BA77 BA78 BA91 DA07 DA08 DA09

Claims (12)

[Claims] 1. A flash control system for remotely photographing an external flash separated from a camera by an optical signal from the camera, the camera comprising: a camera light emitting source; and an appropriate exposure amount based on a photometric result. A light emission amount setting means for setting the light emission amount of the camera light emission source for obtaining a part, and an external flash for calculating information corresponding to the light emission amount of the external flash for obtaining all the rest of the proper exposure amounts Information calculation means, light signal generation means for generating a light signal based on information corresponding to the light emission amount of the external flash and light emission timing of the external flash, and starting light emission of the camera light emission source according to the light emission timing And a camera light source light emitting means for causing the camera light source to emit light at the set light emission amount of the camera light source. The flash includes a flash light source, light signal detecting means for detecting the light signal from the camera, and light emission of the flash light source according to information corresponding to the light emission amount of the external flash transmitted by the light signal. A flash control system comprising: a light emission amount control unit that controls an amount; and a light emission timing control unit that causes the flash light emission source to emit light at a light emission timing of the external flash determined by the light signal. 2. The optical signal generating means generates an optical signal by causing the camera light emitting source to emit light a plurality of times, and generates a light signal between a first light emission and a subsequent second light emission among the plurality of light emissions. 2. The flash control system according to claim 1, wherein a light emission interval is made to correspond to a light emission amount of the external flash, and the second light emission is performed at the light emission timing. 3. The optical signal generating means generates an optical signal by causing the camera light source to emit light twice.
2. The flash control system according to claim 1, wherein a light emission interval of the first flash corresponds to a light emission amount of the external flash, and a second flash is performed at a flash timing of the external flash. 4. The camera according to claim 1, wherein said camera has a detecting means for detecting light emitted from said camera light emitting source, and an integrating means for detecting an integrated value corresponding to a total light amount of said light. After the start, when the integrated value reaches a reference value corresponding to the light emission amount of the camera light source, the camera light source light emission unit stops the light emission of the camera light source, and the external flash is the external flash. A light emission interval measuring means for measuring a light emission interval of the light signal corresponding to a light emission amount, and when the light signal detection means detects light emission at the light emission timing, the light emission timing control means sets the flash light emission source When the light emission amount of the flash light emission source reaches the light emission amount corresponding to the light emission interval measured by the light emission interval measurement means, the light emission amount control means 4. The flash control system according to claim 2, wherein light emission of the flash light source is stopped. 5. The light emission amount setting means sets the light emission amount of the camera light emission source to obtain １ ／ of the proper exposure amount, and the external flash information calculation means sets ２ of the proper exposure amount. 5. The flash control system according to claim 4, wherein information corresponding to a light emission amount of the external flash for obtaining the information is calculated. 6. 6. The flash control system according to claim 1, wherein the camera has timing setting means for setting a flash timing of the external flash based on information corresponding to a light emission amount of the camera light source. . 7. The flash control system according to claim 1, wherein said camera light source light emission means causes said camera light source to emit light after a predetermined time has elapsed from said light emission timing. 8. The flash control system according to claim 1, wherein the information corresponding to the light emission amount of the external flash is information corresponding to an aperture value. 9. A camera body, a camera light source, a light amount setting means for setting a light amount of the camera light source for obtaining a part of the proper exposure amount, and all remaining light sources of the proper exposure amount Remaining light emission amount information calculating means for calculating information corresponding to the remaining light emission amount for obtaining the light emission timing based on the information corresponding to the remaining light emission amount and the light emission timing, and provided outside the camera body. An optical signal transmitting means for transmitting light to the light emitting source, and a camera light emitting source for starting the light emission of the camera light emitting source in accordance with the light emitting timing and emitting the camera light emitting source with the set light emitting amount of the camera light emitting source A camera comprising: a light emitting unit. 10. The camera according to claim 9, wherein the light emission amount of the camera light emission source is for obtaining one third of the proper light emission amount. 11. The camera according to claim 9, wherein the camera light source light emission unit starts light emission of the camera light source after a lapse of a predetermined time from the light emission timing. 12. The camera according to claim 9, wherein the information corresponding to the remaining light emission amount is information corresponding to an aperture value.