JPH04343343A - Camera system capable of wireless flash photographing - Google Patents

Abstract

PURPOSE:To prevent operation error of a subordinate flash due to other flashing light and to provide the camera system where wireless flash photography can be carried out where influence to exposure on a film due to a main flash on a camera side transmitting discrimination signal is reduced even when the discrimination signal is complicated by outputting the discrimination signal to discriminate that it is the signal for wireless flash photography by the main flash before a start of one act of scanning of a shutter. CONSTITUTION:The discrimination signal for discriminating that it is the signal for the wireless flash photography is outputted by light emission by a flash 4 integrated to the camera before the start of one act of scanning of a shutter. This light is received by an outside flash B. Discrimination is carried out whether or not it is the correct discrimination signal. If it is the correct discrimination signal, the flash light emission is carried out after that.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a main flash that is built into or connected to a camera, and a sub-flash that is used without being connected to the camera and whose emission is controlled wirelessly.
(Wireless flash)

0002

2. Description of the Related Art In this type of camera system, when performing wireless flash photography, the main flash is emitted as a signal to start firing the wireless flash (for example, Japanese Patent Laid-Open No. 2-26
(See Publication No. 4229). However, when taking pictures with this wireless flash, there is a risk that it may malfunction due to light from other flashes. To prevent this, it is necessary on the wireless flash side to identify the signal by measuring the pulse interval of the light emission start signal from the main flash. In this way, as a wireless flash system in which the sub-flash receives an identification signal from the main flash, identifies it, and emits light, for example, Japanese Patent Laid-Open No. 58
There is one as shown in Japanese Patent No.-72931.

0003

However, in the system for transmitting an identification signal as disclosed in the above-mentioned publication, the identification signal is also a light emission instruction signal, and this identification signal is also exposed. Therefore, if the identification signal becomes complicated due to the use of multiple signal transmission channels, it becomes impossible to ignore the influence of the light intensity of the main flash on the camera side that transmits the identification signal on the shooting exposure, and due to this, the exposure by the wireless flash cannot be ignored. The exposure ratio to As a result, for example, when wireless flash photography is performed with the intention of preventing red-eye by placing the flash away from the optical axis of the camera's photographing lens, the effectiveness of the red-eye countermeasure will be reduced. Furthermore, as the identification signal becomes longer, the shutter fully open time also needs to be longer. The present invention solves the above-mentioned problems by outputting an identification signal from the main flash to identify it as a signal for wireless flash photography before the start of one-stroke movement of the shutter. It prevents the secondary flash from malfunctioning due to flash light, and also reduces the influence of the main flash on the camera side, which transmits identification signals even if the identification signal becomes complex, on film exposure. The purpose of the present invention is to provide a camera system capable of wireless flash photography without causing any adverse effects.

0004

[Means for Solving the Problems] In order to solve the above problems, the invention according to claim 1 provides a dimmable main flash that is built in or connected to a camera and outputs a light emission control signal; In the camera system capable of wireless flash photography, the main flash is equipped with a dimmable sub-flash that is used without any need to operate and emits light wirelessly upon receiving the control signal, and the main flash It has an output means for emitting and outputting an identification signal for identifying that the signal is for wireless flash photography, and the sub-flash receives the identification signal and identifies whether the identification signal is correct. This device has an identification means that allows the flash to switch to wireless flash emission operation. According to a second aspect of the invention, the identification signal has a plurality of forms. In the example below, the output means is a microcomputer M built in the camera A.
C1 and the flash 4, and the identification means is composed of the light receiving section 34 of the sub-flash B and the microcomputer MC2.

[0005]

According to the structure described in claim 1, an identification signal for identifying a signal for wireless flash photography is emitted by the main flash before the start of one-stroke movement of the shutter. When the sub-flash receives the identification signal and identifies that the signal is correct, it shifts to wireless flash emission operation. According to the configuration described in claim 2, the identification signal is outputted in a form desired by the user, thereby making it possible to transmit a plurality of types of identification signals. In the following embodiment, this action corresponds to the processes #458 to #466 in FIG. 20.

[0006]

As described above, according to the present invention, an identification signal for identifying a signal for wireless flash photography is emitted from the main flash before the start of one-act running, and the sub-flash emits the identification signal for identifying the signal for wireless flash photography. By receiving the light and identifying whether the signal is correct before emitting light, it is possible to prevent the sub-flash from malfunctioning due to other flash light. In addition, even when the identification signal becomes complex, it does not affect the exposure time.
In addition, it is possible to reduce the influence of the main flash for transmitting identification signals on the exposure of the film, and therefore increase the effect when shooting wirelessly by moving the sub-flash away from the camera to prevent red-eye. Can be done.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a view of a camera A and a wireless flash B to which the present invention is applied, viewed from the back cover side. First, the camera A side will be explained. Camera A has a release button 1, a mode change button 2, a test flash button 3, and a built-in flash 4. By pressing the release button 1 one step, you can measure the brightness of the subject, measure the distance to the subject (or detect the focus),
and focusing, and exposure by pushing in two steps. Mode change button 2 is
This is used to switch between normal flash mode and wireless flash mode. The test flash button 3 outputs a signal to fire the test flash of wireless flash B by pressing it in the wireless flash mode.When firing the test flash, hold the camera A with your right hand.
The wireless flash B is placed on the right side of the pentaprism (hereinafter simply referred to as penta) section so that it can be operated with the left hand.

The built-in flash 4 is rotatably attached to the top of the penta, and has two states: a pop-up state in which the light-emitting part moves away from the optical axis of the photographing lens, and a retracted state in which the light-emitting part is pushed down. Flash firing is only possible when it is in the pop-up state. If the camera is in the stored state when it is determined that flash emission is necessary due to low brightness, etc.
Pop up automatically. When it is in the pop-up state, pressing it from above will put it in the stored state. In addition to being used when taking pictures with a flash at low brightness, it is also used as a control signal source when taking pictures with wireless flash B. An external wireless flash can be attached to the camera side connector 5, and communication with the wireless flash is performed through six terminals to be described later. Note that on cameras with an AE lock function, or cameras with a spot metering function that measures only the center of the subject, the AE lock button, SPO
Although the T photometry button is located on the right side of the pentameter portion like the above-mentioned test flash button 3, it is also possible to use these buttons as the test flash button 3.

Next, wireless flash B (hereinafter referred to as flash B) will be explained. The mode display section 6 displays the normal flash mode and the wireless flash mode, and the charging completion display section 7 displays the completion of charging of the light emitting capacitor of flash B. These display sections 6,
7 protrudes above the flash B, so it can be seen from the front of the flash B as well. The channel selection unit 8 is a switch for switching the wireless signal in the wireless flash mode to avoid interference with other wireless flashes. The flash side mode change button 9 is used to switch between the normal flash mode and the wireless flash mode. The wireless flash side connector 10 can be attached to the camera side connector 5. The connector 10 has a shoe switch (not shown) that detects that the flash B is attached to the camera A. At this time, the built-in flash 4 is configured to be housed in the camera A, and when the flash B is attached to the camera A and a photograph is taken, the built-in flash 4 and the flash B do not emit light at the same time.

FIG. 2 is a front view of flash B to which the present invention is applied. In the figure, the light receiving window 11 is
It is for receiving a wireless signal from camera A in the wireless flash mode, and has a built-in light receiving section 34 shown in FIG. 5, which will be described later. Projecting above the flash B are the mode display section 6 and the charging completion display section 7. FIG. 3 shows the external shape of a stand C for a flash B to which the present invention is applied. There is a recess 12 in the upper part having the same shape as the camera side connector 5, to which a flash B can be attached. In the wireless flash mode, by attaching to this stand C, the flash B can be placed and used. A tripod hole may be provided at the bottom of the stand C or the flash B so that the flash can be mounted on a tripod.

FIG. 4 is a block diagram of camera A to which the present invention is applied. Sequence control, exposure calculation, etc. are performed by a microcomputer (hereinafter referred to as microcomputer) MC1. The photometry section 21 is a block for measuring the brightness of a subject, and the distance measurement section 22 is a block for measuring the distance to the subject. The display section 23 is constituted by an LCD, LED, etc., and displays the number of photographic films, shutter speed, aperture, photographing mode, etc. The shutter section 24 is composed of a focal plane shutter, and the microcomputer M
The operation is controlled by C1 according to the first-act running start signal from the terminal 1C and the second-act running start signal from the terminal 2C. When the running of the first act is completed, a first act running completion signal (SX="L") is output to the terminal SX. The aperture section 25 controls the aperture diameter based on a signal from the microcomputer MC1.

The flash section 26 includes a booster circuit, a light emitting capacitor (hereinafter referred to as a main capacitor), a discharge tube, etc., and corresponds to the built-in flash 4 in FIG. The flash unit 26 uses an IGBT in the discharge loop of the discharge tube, and is capable of controlling the light emission time, and is connected to the microcomputer MC1 via a clip switch SCRP. When the clip switch SCRP is connected to the flash section 26, light is emitted while TRG1 is "L". The clip switch SCRP is connected to the flash section 26 side when the built-in flash is housed, and to the terminal X side, which will be described later, when the built-in flash is in the pop-up state. RDY1 is a terminal where the voltage of the main controller is divided by resistance. Microcomputer MC1
A/D converts the voltage of RDY1 and detects the state of charge of the main controller. CHG1 is a terminal for controlling the voltage boosting of the boosting circuit, and boosts the voltage while CHG1 is set to "L".

The focus control section 27 drives the photographic lens in order to control the focus of the photographic lens based on a control signal from the microcomputer MC1. The light emitting unit driving unit 28 is a block for pop-up of the built-in flash 4, and is connected to a solenoid MG, which is turned on by a signal from the microcomputer MC1. Built-in flash 4
is biased in the pop-up direction and is locked in the storage position. By turning on the solenoid MG with the flash B not attached to the camera A, the built-in flash 4 enters the pop-up state.

The integrating circuit 29 is activated when IST is set to "L", and integrates the reflected light from the subject during flash photography, and when a predetermined amount of light is reached, IN
Output “L” to T. The predetermined amount of light is set by a signal from the terminal LEVEL from the microcomputer MC1. Therefore, when shooting with flash, by changing the predetermined light amount, the amount of flash light to be exposed can be set to ``appropriate'' or ``one step under''.
, "1 stage over", etc. can be controlled in detail. Normally"
The photometering and distance measurement switch S1 is set to “appropriate” in Figure 1.
Press the release button 1 one step to turn it on, and the microcomputer MC
1 performs photometry and distance measurement in the photometer 21 and distance measurement section 22, performs exposure calculations, drives the focus lens, etc. The release switch S2 is turned on by pressing the release button 1 two steps and starts exposure. Mode change switch SM
The OD is turned on by pressing the mode change button 2, and each time it is turned on, the normal flash mode and the wireless flash mode are switched.

The test light emission switch STST is turned on by pressing the test light emission button 3 shown in FIG. By turning on the wireless flash mode, the microcomputer MC1
outputs a signal for flash B test emission to the flash section 26. Terminal X, SCK, SIN
, SOUT, SREQ, and GND are used to communicate with flash B when flash B is attached to camera A, the shooting mode, the charging status of flash B's main controller, the start of light emission,
This is a terminal for communicating information such as stop timing, and is connected to the flash B via the aforementioned connector 5. G
ND is a ground, and X is a terminal for controlling the light emission time of the discharge tube of flash B in the normal flash mode.

A boosted light emitting section (to be described later) of the flash B has the same structure as the flash section 26 described above. When flash B is attached to camera A, terminal
The TRG1 is connected to. And TRG1 is “L”
During this time, the discharge tube is discharging. SCK,S
IN, SOUT are for serial transmission and reception.
SREQ is a terminal for requesting communication from flash B. When communicating with flash B, first set SREQ to “L”
After a predetermined time, a serial clock is output from SCK and input from SIN. Then, if predetermined data is input and it is determined that flash B is attached, communication with flash B is performed.

FIG. 5 is a block diagram of flash B to which the present invention is applied. The microcomputer MC2 performs sequence control of the flash B. The boosted light emitting unit 31 is a block for boosting the voltage of the main controller (flash side), discharging the discharge tube, etc., and has the same configuration as the flash unit 26 on the camera side in FIG. 4 described above. CHG2 performs boost control, RDY2 monitors the state of charge of the main controller, and TRG2 controls light emission time. The display control unit 32 controls the display of the mode display unit 6 and charging completion display unit 7 in FIG.
is connected, and the signal from the microcomputer MC2 causes it to go low.
Controls turning on and off of ED1 and LED2. LED1 is the charge completion display section 7, and LED2 is the mode display section 6.
to do. The details of this light emission pattern of turning on and off will be described later.

The zoom drive unit 33 is a block that changes the distance between the reflector of the flash B and the flash panel in accordance with the focal length of the photographic lens, and changes the light distribution characteristics of the flash. The light receiving section 34 is a block for receiving a wireless signal from the camera A. When this signal is received, WLIN becomes "L". The channel selection switch SCH is turned on/off by sliding the channel selection section 8 in FIG. When it is ON, it is channel "1", and when it is OFF, it is channel "2". S.S.
HOE is a shoe switch that turns on when flash B is attached to camera A. Mode change switch SWL
is turned on when the flash side mode change button 9 is pressed, and the normal flash mode and wireless flash mode are switched each time the flash side mode change button 9 is pressed.

[0019]Terminals X, SCK, SIN, SOUT, SR
When flash B is attached to camera A, EQ and GND are connected to terminals with the same names on the camera A side in FIG. The charging status information of the main controller is transmitted through these terminals.
Various information such as channel information and photographic lens focal length information is exchanged with camera A. As described above, X is a terminal for controlling the light emission time of the discharge tube, and while X is "L", the microcomputer MC2 sets TRG2 to "L". Also SC
K, SIN, and SOUT are for serial communication, so SREQ
is a terminal for serial communication request. When SREQ is set to “L” by the microcomputer MC1, the microcomputer MC
2 sets various information in a register for serial communication. Then, serial communication is performed in synchronization with the clock pulse input from SCK. The names of the camera A side terminal and flash B side terminal that are connected to each other are the same, and the microcomputer MC2 outputs serial signals from SIN and SOUT.
Perform serial signal input.

FIG. 6 shows the light emission pattern of LED1 and LED2 of the display control section 32 mentioned above. The LED 2 is controlled to turn on in a predetermined light emission pattern as shown in the figure, depending on the selected mode, and the LED 1 is controlled to turn on when charging is completed. Note that the LED 1 is controlled so as to be superimposed on a light emission pattern indicating each mode. FIG. 7 is a circuit diagram of the light receiving section 34 mentioned above. Photodiode P
When light is incident on D, a current flows from the photodiode PD in accordance with the intensity of the incident light. This current is converted into voltage by resistor R1. Then, the stationary light is removed by a differentiating circuit composed of capacitor C1 and resistor R2, and only the signal light is F.
It is input to the ET gate. Therefore, the light receiving unit 34 outputs "L" from WLIN to the microcomputer M only when it receives the signal light.
Input to C2.

FIG. 8 is a time chart showing the operation in wireless flash mode according to this embodiment. In wireless flash mode, release switch S2 is set to O.
When N is selected, the built-in flash 4 of camera A emits an identification signal. In this example, 1 for channel 1
It is designed to output two signals at millisecond intervals, and for channel 2, two signals at 2 millisecond intervals. Then, the shutter starts running one curtain, and upon completion of the first curtain running, it outputs an X signal to instruct the flash B to start emitting light. When it is determined that the flash B belongs to the channel to which the identification signal has been set, it starts emitting light at a predetermined time and interval based on the X signal. Camera A has built-in flash 4 after the X signal
Then, the current caused by the reflected light from the subject of flash B is integrated by the integrating circuit 29 in the camera A, and when a predetermined voltage is reached, S is used to instruct flash B to stop emitting light.
Outputs TOP signal. When this STOP signal is input, flash B stops emitting light. Thereafter, after a predetermined period of time has elapsed, camera A starts two-act running and ends exposure. Details of these control methods will be described later.

The following table shows the number of times the flash B emits light and the time it takes to emit light when the flash B receives the X signal and starts emitting light intermittently. This light emission count-light emission time data is stored in the microcomputer MC2. Then, the light emitting time is controlled to become longer every predetermined number of times. Light emission is performed a maximum of 37 times, and the light emission interval is 200 microseconds. The number of times of light emission is the number of times until the light emission becomes impossible when intermittent light emission is performed at the above-mentioned timing when charging of the main controller is completed, and changes depending on the capacity of the main controller. In this embodiment, the light emitting time is lengthened in steps, but the steps may be further increased, or the light emitting time may be lengthened each time the light is emitted.

Next, the test light emission function in the wireless flash mode will be explained with reference to FIG. This function is used to check whether the signal light is being transmitted and received normally, whether the set channel is correct, and whether the wireless flash is fully charged before actually taking a picture. Figure 9 shows the time chart. In the wireless light emission mode, when the above-mentioned test light emission button 3 is turned on, a signal different from the above-mentioned identification signal is transmitted. In this embodiment, for channel 1, there are three signals at 1 mm intervals, and for channel 2, there are three signals at 2 mm intervals. The microcomputer MC2 in flash B receives the identification signal and determines that this signal is a test flash signal for the set channel.
After a delay of 500 milliseconds, the light is emitted.

The operation of the camera system according to the present invention will be explained below based on the flowcharts shown in FIG. 10 and subsequent figures. First, I will explain how the wireless flash works. When the battery is inserted into flash B, the microcomputer MC2 will operate as shown in Figure 1.
0, the operation starts according to the "MAIN" flowchart shown in FIG. First, the shoe switch SSHOE determines whether flash B is attached to camera A or not (#2). The interrupt by the terminal WLIN from the unit 34 is prohibited (#3), and the process proceeds to #6. Also, when the shoe switch SSHOE is OFF, that is, it is not attached to camera A, the mode flag FWL is determined (#4
). The mode flag FWL is a flag for determining the flash mode, and is "1" in the wireless flash mode and "0" in the normal flash mode. If FWL=1 in #4, that is, the wireless flash mode is enabled, the WLIN interrupt is permitted (#5), and the process proceeds to #6. Also, FWL in #4
=0, that is, when it is not the wireless flash mode, proceed to the above-mentioned #3. In #6, a subroutine "Completion Check 2", which will be described later, is executed. This subroutine checks the voltage of the main controller, and if it is lower than a predetermined voltage, it is charged.

After processing "Completion Check 2", the mode change switch SWL is determined (#7), and if the mode switch SWL is ON, the APO timer is reset and started (#8), and the APO timer is reset and started (#8). Proceed to step 10. Here, AP
O stands for auto power OFF, which automatically turns off the power if there is no switch operation or flash firing instruction for a predetermined period of time or more, thereby reducing current consumption. In #10, the flash mode is determined based on the mode flag FWL. When FWL=1, FWL is set to 0 (#11), the aforementioned display control section 32 is instructed to turn off the LED 2 (#12), and the process proceeds to #15. F
When WL=0, FWL is set to 1 (#13), the display control unit 32 is instructed to turn on LED2 (#14), and the process proceeds to #15. The lighting pattern of the LED 2 at this time is controlled as shown in FIG. 6 according to the selected wireless mode. If the mode switch SWL is OFF in #7, the process proceeds to #15 without performing the above operation. Thereby,
Every time the mode switch SWL is turned on, the normal flash mode and wireless flash mode are switched.

At #15, it is determined by the shoe switch SSHOE whether or not flash B is attached to camera A (#15). When the shoe switch is ON, that is, when the shoe switch is attached, the focal length data of camera A's photographic lens is read from the memory (#16), and the light distribution characteristics of the flash are set to be appropriate for the angle of view of the focal length. Calculate the flash zoom position (#17), drive the flash zoom to the target position (#18), and #
Proceed to step 24. When the shoe switch is OFF in #15, that is, when it is not attached, the mode is determined using the mode flag FWL (#19). When FWL=1, that is, in the wireless flash mode, the zoom flash is driven to the wide end in order to widen the light distribution characteristics of the flash (#20), and the process proceeds to #23.

In #23, the APO timer determines whether one hour has elapsed or not, and if it has not elapsed, “M
Return to "AIN" and repeat the above operation.If it has passed, #
Proceed to step 25. In #19, when FWL=0, that is, in the normal flash mode, when the process proceeds to #24, it is determined by the APO timer whether 4 minutes have elapsed. If four minutes have not elapsed, the process returns to "MAIN"; if it has, the process proceeds to #25, instructs the display control section 32 to turn off the LEDs 1 and 2, and the microcomputer MC2 enters the "STOP mode". In the "STOP mode", the microcomputer MC2 turns off the power to each block of the flash mentioned above, and also stops the transmitter itself to minimize current consumption. Returning from the "STOP mode" requires changes in each of the switches and the terminal SRE.
This is performed when Q requests serial communication from camera A, and upon recovery, the operation starts from the above-mentioned "MAIN".

Next, the processing operation of the subroutine "Sufficiency Check 2" mentioned above will be explained using FIG. 12. First, reset the charging flag FRDY2 to “0” (#101)
. The charging completion flag FRDY2 is a flag for determining whether or not the battery is being charged, and is set to "1" when charging is in progress and "0" when not charging. Next, in order to detect the charging voltage of the main controller, terminal R
The voltage of DY2 is A/D converted (#102), and the flash mode is determined (#103). When FWL=1, that is, in the wireless flash mode, it is determined whether or not charging is in progress using the charging flag FRDY2 (#1
04). If charging is in progress, it is determined from the A/D result of RDY2 whether the voltage of the main controller is 320V or higher (
#105), if the voltage has reached 320V, stop boosting (#106), and enable the interrupt of the terminal WLIN (
#107), reset the charging flag FRDY2 to "0"(#123), and proceed to #119. If the main controller voltage has not reached 320V, return to #102. In #104, if charging is not in progress, the process proceeds to #108, where it is determined whether the main controller voltage is 300V or less. When the main controller voltage is below 300V, interrupts at the terminal WLIN are prohibited (#109). Then start boosting (#
110), and sets the charging flag FRDY2 to “1” (
#111), instructs the display control unit 32 to turn off the LED 1 (#112), and returns to #102.

In #103, if FWL=0, that is, the wireless flash mode is not in effect, the process proceeds to #113. The operation from #113 onwards is different from the operation in the wireless mode described above, and includes control of enabling and disabling the interrupt of the terminal WLIN, and changing the voltage of the main controller from 320V to 300V to 30V.
The only difference is that the voltage changes from 0V to 270V, so the details will be omitted. Due to the above, when in wireless flash mode, the voltage of the main controller must be 300V to 3.
By keeping the voltage at 20V and the voltage during normal flash from 270V to 300V, the main controller voltage during wireless flash mode is higher than that during normal flash mode, and voltage variations are suppressed to a small level. In #119, the channel selection switch SCH is set to “1”.
” or “2”, and when it is channel 1, LED1
Instruct the display pattern to become the display of C in Figure 6 (
#120), when channel 2 is selected, the display controller 32 is instructed to display B in FIG. 6 (#121), and the process returns. Further, when proceeding to #122 in the normal flash mode, the display control unit 32 is instructed to turn on the LED 1, and the process returns.

Next, the state of communication when flash B is attached to camera A will be explained with reference to FIG. When the aforementioned terminal SREQ is set to “L”, the microcomputer MC2
An interrupt is generated, and the interrupt handling routine from "INTS" is started. Microcomputer MC2 synchronizes with the serial clock from terminal SCK from microcomputer MC1 built in camera A, and transmits data determined in advance with microcomputer MC1 via terminal SIN (#151), and exchanges various data with camera A. Communicate (#152) and return.

In this communication, for example, data such as the focal length of the photographing lens, flash mode, shooting mode, test flash instruction, etc. are transmitted from camera A to flash B, and data such as the charging status of the main controller and the flash flash are transmitted from flash B to camera A. Data such as the mode, selected channel, and tuned shutter speed are transmitted and received according to a predetermined format. The reason for transmitting the synchronization speed here is that when using a wireless flash other than the one in this example, the number of times that intermittent flashing can be performed differs depending on the main controller capacity, etc. This is because the total time until the intermittent light emission ends is different. Then, by transmitting the flash mode data as described above, when flash B is attached to camera A, the flash mode on the flash B side becomes the same as the flash mode set on the camera A side.

In this embodiment, the flash mode set on the camera A side is given priority, but the flash mode data is sent from the flash B to the camera A side, so that the flash mode set on the flash B side is given priority. Priority may be given to flash mode. Further, by transmitting and receiving the flash mode, the flash mode can be set for either camera A or flash B. By the way, camera A
sets the wireless flash mode channel according to the channel data from flash B. In this embodiment, the channel setting for the flash mode on the camera A side is performed by attaching the flash B to the camera A, but like the flash mode described above, a channel setting switch is also provided on the camera A side. It may also be possible to set the channel with camera A alone.

Next, the interrupt processing routine for the terminal WLIN will be explained using FIGS. 14 and 15. In the wireless flash mode, a wireless signal from the camera built-in flash 4 is received, and WLIN from the light receiving section 34 is
Upon receiving the "L" signal, the microcomputer MC2 starts operating from "INTWL" to identify the signal, and determines whether the next signal is input. First, timer TWL is started (#201). The operating speed of microcomputer MC2 is fast enough, so timer TWL is set to WLIN.
It starts almost simultaneously with the change from "H" to "L". Then, wait for a maximum of 2.2 milliseconds (#202, #203) for WLIN to change from "H" to "L" again (receiving the second signal), and wait for the WLIN to change from "H" to "L" again (receiving the second signal) for a maximum of 2.2 milliseconds (#202, #203). If not, it is considered that the first signal was noise, and the process returns.

2. When the level changes from "H" to "L" within 2 milliseconds, it is determined whether the channel set for flash B is "1" or "2"(#204). For channel 1, timer TWL is 0.9 milliseconds or more and 1.
Determine whether it is 1 millisecond or less (#205, #2
06). As a result, the interval between the first and second signals is 0.
．． It can be checked whether the time is between 9 milliseconds and 1.1 milliseconds. If not, both of the two signals are considered to be noise, and the signal is returned. If so, it can be confirmed that the two signals mentioned above were indeed identification signals. Therefore, start timer TWL again (#207),
Furthermore, it is determined whether the next signal comes between 0.9 milliseconds and 1.1 milliseconds. In other words, WLIN is “H”
Wait a maximum of 1.1 milliseconds for the change from “L” to “L” (#2
08, #209), “H” before 1.1 milliseconds elapse.
If the signal does not change from “L” to “L”, the signal at 1 millisecond interval will be 2
Therefore, it is identified that the wireless mode is channel 1, and the “W” from #221 onwards is identified.
Proceed to "L emission mode". If the change occurs within 1.1 milliseconds, proceed to #210, determine whether 0.9 milliseconds have elapsed, and if 0.9 milliseconds or more have not elapsed, It is thought that it was noise, so it returns.If 0.9 milliseconds or more have passed, it means that three signals with 1 millisecond intervals have been input, so it is identified that it is in test mode for channel 1. , proceed to the "test mode" below #217.

#204 to #21 for channel 2
1, and in #211 to #216, the same processing as described above is performed except that the timer time is different. In other words, in this case, the signal interval between the first and second shots is 1
．． It is checked whether it was between 8 ms and 2.2 ms, and whether the next signal comes between 1.8 ms and 2.2 ms. If there are only two signals, it is determined that the wireless mode is on channel 2, and if there are three signals, it is determined that the test mode is on channel 2.

In the "test mode", first wait 500 milliseconds (#217), then wait 30 microseconds at terminal TRG2.
Perform a test flash by setting “L” (#21
8, #219, #220), reset the APO timer (#239), and return. In “WL emission mode”, start timer TWL again (#221),
Wait up to 10 milliseconds for WLIN to change from “H” to “L”, that is, for the X signal to arrive (#222, #224)
. If WLIN does not change from "H" to "L" for 10 milliseconds, the process advances to #239 and returns. If the change occurs within 10 milliseconds, then it is determined whether 5 milliseconds or more have elapsed (#223), and if 5 milliseconds or more have not elapsed, the process returns. Therefore, timer T at #221
If there is no change in WLIN from "H" to "L" within a range of 5 milliseconds or more and 10 milliseconds or less from the start of WL, the process returns.

To explain the reason for this, when shooting in the wireless flash mode, camera A to which the present invention is applied runs the first act immediately after outputting the identification signal, and immediately after the first act has completed running. It outputs an X signal instructing the start of light emission. By the way, there is some variation in the time from the start to the completion of the first act, and also due to environmental changes such as temperature, microcontrollers MC1 and MC2
It is conceivable that some error may occur in the clock operation. The times of 5 milliseconds or more and 10 milliseconds or less in #223 and #224 are set so that they always fall within this range when the shutter and microcomputer operate normally. Note that this time width varies depending on the performance of the shutter and the microcomputer, and is not limited to the above. In addition, when determining the above-mentioned identification signal, the time width (±10%
) is provided for the same reason.

When the terminal WLIN changes from "H" to "L" within the above time, the process proceeds to #225, sets the counter n to 1, and proceeds to #226 and subsequent steps. This counter counts the number of times the flash B will emit light intermittently thereafter. Next, set the terminal TRG2 to “L” (
#226), emits light based on the relationship between the number of times of light emission and the time of light emission (see the table above) (#227, #228, #229),
After waiting 10 microseconds (#230), start timer TWL (#231), and for a maximum of 90 microseconds,
It waits for terminal WLIN to go "L", that is, for a stop signal to be output from camera A (#232, #233). 9
If the terminal WLIN becomes "L" before 0 microseconds elapse, the process proceeds to #239, resets and starts the APO timer, and returns. Therefore, no further light emission is performed.

On the other hand, in the above case, the terminal W is connected within 90 microseconds.
If LIN does not become “L”, proceed to #234,
By looking at the counter n, it is determined whether or not light has been emitted 36 times (#234). If 36 times of light emission has not been performed, the counter n is set to n+1 (#235), and #
Returning to 226, the above-described operations are repeated. When it is determined in #234 that the 36th light emission has been completed, the process proceeds to #236, where the final 37th light emission for 500 microseconds is performed (#237
), then reset and start the APO timer and return. By this 500 microsecond light emission, almost all of the charge in the main controller is discharged.

Next, the operation on the camera A side will be explained. When the battery is inserted into camera A, the microcomputer MC1 is activated as shown in Figure 16.
The operation starts from "START". First, it is determined whether the photometric distance measurement switch S1 is ON or OFF (#301). If it is ON, proceed to "S1" described later, and if it is OFF, determine whether the mode selection switch SMOD is ON or OFF (
#302). When this is ON, the process advances to #307 and the mode flag FMOD is determined. Here, the mode flag FMOD is a flag for determining whether the camera A side is in the normal flash mode or the wireless flash mode, and is "0" when the normal flash is used and "1" when the wireless flash is used. FMOD=1 at #307
If so, set FMOD=0 (#308), and FMO
When D=0, set FMOD=1 (#309)
, return to #301. That is, the mode selection switch SMO
It is possible to switch between normal flash mode and wireless flash mode each time D is turned on.

If the mode selection switch SMOD is OFF in #302, the process advances to #303 and the mode flag F
The MOD is determined and the normal flash mode (FMOD
If =0), the process returns to #301, and if the wireless flash mode (FMOD=1), the process proceeds to #304 to communicate with flash B, which will be described later. Next, the process proceeds to #305, where it is determined whether or not flash B is attached. When flash B is attached, return to #301,
When not installed, test light button switch STST
Determine whether it is ON/OFF (#306), and if it is OFF, return to #301, and if it is ON, start the "test flash" described later.
Proceed to. Although not described in this flowchart, camera A side also has an auto power-off function similar to flash B, and if the operation switch is not operated for a predetermined period of time, microcomputer MC1 cuts off the power to each block, and also turns off the transmitter itself. and STOP until the operation switch is operated.
state.

Next, the processing operation in "flash communication" will be explained using FIG. 17. First, in order to request serial communication to flash B, connect the terminal SREQ to “
"L"(#351) and cause the microcomputer MC2 built in flash B to generate an interrupt. Then wait 1 millisecond (
#352), serial communication is performed (#353). At this time, the microcomputer MC1 built in camera A outputs the clock for serial communication from the terminal SCK, but at that time,
If a predetermined signal is not input from the terminal SIN, the microcomputer MC1 determines that the flash B is not attached and stops communication. When predetermined data is input from terminal SIN, communication continues according to a predetermined format. Then, when communication of a predetermined number of bits is completed, the process returns.

Next, the flowchart of the above-mentioned "S1" will be explained using FIG. 18. First, the distance measurement unit 22 measures the distance (
#401), determine whether the focus is on (#4
02). If it is not in focus, the AF (not shown) will move to the in-focus position.
The photographing lens is driven by the motor (#403), and #4
Return to 02. When in focus, the distance to the subject is calculated from the lens position (#404), the subject brightness is measured by the photometer 21 (#405), and information such as subject distance, subject brightness, flash mode, etc. Based on the exposure calculation, which will be described later, is performed (#406), and the process proceeds to #407. In #407,
Determines whether the release switch S2 is ON or OFF, and
If N, the process proceeds to "S2", which will be described later. If it is OFF, determine whether the photometer distance measurement switch S1 is ON or OFF (#408).
, if it is ON, the process returns to #401, and if it is OFF, the process proceeds to the above-mentioned "START".

Next, the processing operation of "exposure calculation" will be explained using FIG. 19. First, the flash mode is determined based on the mode flag FMOD (#421). In the normal flash mode (FMOD=0), it is determined whether the subject brightness is lower than a predetermined brightness (#422), and if it is not low brightness, the shutter speed TV and aperture are determined from the program line for natural light photography (not shown). The AV is determined (#423), and the process proceeds to #441, which will be described later. When the subject brightness is low in #422, set the flash flag FF to "1"(#424),
Perform the “flash communication” mentioned above (#425), and #
Proceed to 426. Here, the flash flag FF is a flag for determining whether or not to use a flash during exposure, and is set to "1" when the flash is used, and "0" when not used.

In #426, it is determined whether flash B is attached or not, and if it is not attached, it is determined whether built-in flash 4 is popped up (
#427). If it is not popped up, pop up the flash 4 using the light emitting unit drive unit 28 (#428)
Then, the charging state of the main controller is detected in "Charging completion check 1" to be described later, and if the main controller voltage is insufficient, charging is performed (#429). Then, the shutter speed TV and aperture AV are determined in a normal flash photography program line (not shown) (#430), and the process returns. When flash B is attached in #426, and when flash 4 is attached in #427
If it is popped up, proceed directly to #429. Note that in the normal flash photography program line, the shutter speed is fixed at 1/250, and the aperture changes depending on the brightness of the subject.

When FMOD=1 in #421, that is, the wireless flash mode is set, the above-mentioned "flash communication" is performed (#431), and it is determined whether flash B is attached (#432). Flash B
If it is attached, the process advances to #422 and the same operation as normal flash photography is performed. When flash B is not attached, set flash flag FF to “1” (#43
3) It is determined whether the built-in flash 4 is popped up (#434). If flash 4 has not popped up, pop it up (#435), proceed to "Fullness check 1" described later, check the main controller voltage (#436), and adjust the shutter speed using the wireless flash photography program line (not shown). The TV and aperture AV are determined (#437). When flash 4 is popped up in #434, directly press #436
Proceed to. In the wireless flash program line, the shutter speed is determined by the synchronized shutter speed input through "flash communication", and the aperture is determined by the brightness of the subject.

Next, it is determined whether the subject distance data obtained when the above-mentioned photographic lens is focused is within 1 meter (#438). If it is not within 1 meter, proceed to #441; if it is within 1 meter, shift the aperture AV determined in #437 by one step in the aperture direction (#439
), shift the shutter speed TV one step towards long exposure (
#440), proceed to #441. In #441, #437
The shutter speed TV determined in #440 or the TV shifted in #440 is compared with the camera shake limit shutter speed TVH. Shutter speed TV is camera shake limit Shutter speed TV
If it is faster than H, it returns as is, and if it is slower, it causes the display unit 23 to issue a camera shake warning (#442) and returns. Note that the camera shake limit shutter speed TVH is the lowest shutter speed that does not cause camera shake when a photograph is normally taken, and is set to 1/min the focal length (mm) of a normal photographic lens.

Next, the operation of the above-mentioned exposure and film winding routine "S2" will be explained with reference to FIG. First, the mirror is raised (#451), and the aperture is driven and set to the aforementioned aperture AV (#452). Then, it is determined whether or not to use a flash during exposure based on the flash flag FF (#453). When the flash is not used (FF=0), the process proceeds to #467, and when it is used (FF=1), it is determined whether the flash mode is normal flash mode or wireless flash mode based on the mode flag FMOD (#454). Normal flash mode (FMOD=0)
If so, proceed to #467. When in wireless flash mode (FMOD=1), proceed to #470. In #470, it is determined whether or not a flash is attached. If a flash is attached, the process advances to #467. If the flash is not attached, the process proceeds to #455, where it is determined whether the aforementioned subject distance data is within 3 meters or further than 3 meters. If the distance is within 3 meters, set the trigger time TTRG (described later) to 10 microseconds (
#456), if it is farther than 3 meters, set TTRG to 30
Set it to microseconds (#457) and proceed to #458. Here, the trigger time TTRG is the light emission time of the built-in flash 4 that is caused to emit light when sending a wireless signal such as an identification signal to the flash B.

In #458, #459, and #460, during the trigger time TTRG set as above, the terminal TR
Light is emitted by setting G1 to "L". Then, wait for 1 millisecond when the set channel is "1" and 2 milliseconds when it is "2"(#461,#462,#463), and set terminal TRG1 to "L" for the trigger time TTRG + 10 microseconds ( Proceed to #464, #465, #466) and #467. At #467, exposure is performed according to the "exposure" flowchart described later, and after the exposure is completed, one frame of film is wound up by a film feeding means (not shown) (#46
8) Check the charging state of the main controller using "Charge completion check 1" (described later) (#469), and return to "START".

Next, the exposure operation will be explained using the "exposure" flowchart shown in FIG. First, start the first act (#501), and set the timer SS to measure the shutter speed.
(#502). Then, it is determined whether or not to use the flash during exposure using the flash flag FF (#503), and if the flash is not used, #5
Proceed to step 11. When used, the terminal I from the integrating circuit 29
Enable the NT interrupt (#504), start the operation of the integrating circuit 29 (terminal IST="L") (#505),
Wait for the completion of the first act (terminal SX="L") (#506
). When the first curtain run is completed, the terminal TRG1 is set to "L" to start emitting light (#507). Then, the mode flag FMOD is determined (#508), and when the normal flash mode (FMOD=0) is selected, the process proceeds to #511, and when the wireless flash mode (FMOD=1), it is determined whether the flash is attached or not. Make a determination (#515
) If a flash is attached, the process proceeds to #511; on the other hand, if it is not attached, the process proceeds to #509. and,
Wait for trigger time TTRG (#509) and set TRG1 to "H"(#510). In response to this signal, flash B starts to emit intermittent light in the wireless flash mode. In #511, the timer SS waits for the time corresponding to the aforementioned TV to elapse, prohibits the interrupt of the terminal INT (#512), and starts the second act (#513).
. and as enough time for the second act to complete its run.
Wait 10 milliseconds (#514) and return.

FIG. 22 shows an interrupt handling routine "INTFL" for outputting a stop signal when an interrupt is generated by the terminal INT from the integrating circuit 29 during exposure using a flash. To explain this, when an interrupt occurs, first the mode flag FMOD is
The flash mode is determined by (#551), and when it is the normal flash mode (FMOD=0), the terminal T
Set RG1 to "H" to stop light emission (#558) and return. Wireless flash mode (FMOD=
In case 1), it is determined whether or not a flash is attached (#560), and if it is attached, the process goes to #558.
If it is not attached, a counter n is set to "0"(#552), and the process proceeds to #553. This counter n is for managing the number of light emission stop signals sent to flash B. In #553, terminal TRG1 is set to "L" and after waiting for trigger time TTRG + 20 microseconds x n (#554
), sets the terminal TRG1 to "H"(#555). Next, set the counter n to n+1 (#556), and set the counter n to n+1 (#556).
Check whether it has become 3 (#557), and if not,
Wait 100 microseconds (#559), return to #553, and repeat the same operation. Then, if n=3 in #557, the process returns. Therefore, from “L” of TRG1 to “
The change to "H" is performed three times, and the stop signal is output three times, and as the number of times the light is emitted increases, the light emission time becomes longer.

As described above, the light emission stop signal to flash B in the wireless flash mode is sent multiple times (
In this embodiment, the data is output three times). This is because the intermittent light emission timing of flash B and the timing of the stop signal output from camera A are not synchronized, so if only one stop signal is output, the stop signal overlaps with flash B's light emission, causing flash B to stop. This is because the signal may not be detected. In this embodiment, the above problem is solved by outputting the stop signal multiple times, but the light emission timing data of flash B is stored in advance on the camera A side before wireless flash photography, and the light emission timing data is based on the light emission timing data. The stop signal may be output during a time when the flash B is not emitting light. This timing data may be written into a ROM within camera A, or may be transmitted from flash B to camera A through communication between flash B and camera A. Further, a light receiving section similar to the flash B may be provided on the camera A side, and the light receiving section may detect when the flash B is not emitting light and output a stop signal. By doing so, it is possible to reliably stop the flash B from emitting light by just outputting the stop signal once.

Furthermore, in this embodiment, after outputting the identification signal,
Although the light emission is started in response to a signal, the light emission may be started after waiting a predetermined time after the identification signal. This predetermined time is sufficient time for the first act to complete its running after it starts running (10 milliseconds in the case of the camera of this embodiment). By doing so, the X signal for starting light emission becomes unnecessary. Furthermore, in this embodiment, the flash B starts to emit light intermittently in response to the X signal for instructing the start of light emission, and the camera A side integrates the reflected light from the subject and outputs a stop signal when it reaches a predetermined value. Although the intermittent light emission is stopped, as another example, the flash B is configured to emit light only once based on the above-mentioned light emission count - light emission time data each time the X signal is output, and to reduce the light emission from the subject. Camera A may continue to output the X signal until the reflected light reaches a predetermined value. This eliminates the need for a stop signal. A time chart at this time is shown in FIG.

FIG. 23 shows the wireless flash mode.
This is a "test light emission" routine that outputs a signal for performing a test light emission. To explain this, first, “
The charging state of the main controller is detected by "Charge completion check 1"(#651). Then, the counter n is set to 1 (
#652), terminal TRG1 is set to “L” for 30 microseconds.
” and emit light (#653).Then, determine the selected channel (#654), wait 1 millisecond for channel 1, and 2 milliseconds for channel 2 (#655, #65).
6), for 30 microseconds + 10 microseconds x n, terminal TRG1 is set to "L" to emit light (#657), then counter n is set to n+1 (#658), and counter n becomes 3.
Check whether it has become (#659). Repeat #654 to #658 until the counter n reaches 3. When the light emitting signal is output three times and the counter n reaches 3, the process proceeds to #660, executes "filling check 1", and proceeds to "START". Note that when outputting the test flash instruction signal, if camera A has already measured the distance and has subject distance data, the flash duration should be changed depending on the subject distance, just as when transmitting the identification signal. Good too.

FIG. 24 shows how to check the charging state of the main controller of the built-in flash 4 of camera A and to control charging.
This is the routine of "Charging Check 1". To explain this, first, the charging flag FRDY is set to "0"(#701
). The charging flag FRDY is a flag for determining whether or not charging is in progress, and is "1" during charging, and "0" otherwise. Next, the charging information of the main controller is read by A/D converting the output of the terminal RDY1 (#702). Then, the flash mode is determined using the mode flag FMOD (#703), and if it is not the wireless flash mode (FMOD = 0), the process proceeds to #709, and if it is the wireless flash mode (FMOD = 1), then the charging flag FRDY is used to determine the flash mode. Determine whether charging is in progress (#7
04). #706 when not charging (FRDY=0)
Proceed to A of RDY1 when charging (FRDY=1)
Based on the result of /D conversion, it is determined whether the main controller voltage is 320V or more (#705). Main controller voltage is 320
When the voltage has not reached V, the process returns to #702, and when it is 320V or higher, the boosting is stopped (#714) and the charging flag FRDY is set.
is set to "0"(#715) and returns. #706
Now, it is determined whether the main controller voltage exceeds 300V. If it exceeds 300V, return to #702, if it does not exceed, start boosting (#707), set charging flag FRDY to "0"(#708), and #70
Return to 2. Note that the processes in #709 to #713 are the same as in the wireless flash mode except that the main controller voltage is changed from 320V to 300V and from 300V to 270V, so a description thereof will be omitted.

By the way, in this embodiment, the built-in flash 4
In order to minimize the effect on exposure, when the distance is close, the aperture is narrowed down and the flash time is shortened as shown in the routines in Figures 19 and 20, but information such as film sensitivity etc. It is also possible to take this into consideration. Furthermore, in this embodiment, during wireless flash photography, the built-in flash 4 of the camera is used only to transmit signal light to flash B, and the amount of contribution to film exposure is minimized, and flash B is used to expose the subject. That's what I do. However, as described above, the flash light integration circuit 29 of this embodiment can set the integration level. Therefore, for example, set the integration level to two-thirds of the appropriate exposure amount.
Set the built-in flash 4 so that it fires wirelessly, set the integral level to one-third of the appropriate exposure amount in response to the stop signal transmission, and fire the built-in flash 4 until INT = "L". This will give a three-dimensional effect, and it will also be possible to take photos with less strong shadows. Furthermore, by appropriately changing the integration level, it is possible to change the ratio of the amount of contribution of the flash B and the built-in flash 4 to the exposure. In addition, if proper exposure is not achieved even after flash B fires all the times, the photograph will be underexposed in this embodiment, but in such a case, the built-in flash 4 can be fired until the INT="L" is reached to correct the exposure. You may try to make up for it.

Furthermore, in this embodiment, when shooting in the wireless flash mode, the built-in flash 4 is configured to pop up automatically if it is not already popped up, but in a camera of the type that pops up manually, A warning should be issued to encourage this. Furthermore, in this embodiment, in the wireless flash mode, test firing of flash B is possible by operating test firing button 3, but when flash B is attached to camera A, test firing button 3 is operated. When this occurs, the test flash B may be emitted at the terminal X. By doing so, it becomes possible to emit a test light even if there is no test light emission button on the flash B side. Furthermore, if the flash B is not attached in the normal mode, the built-in flash 4 may be used to emit a test light. Note that in the above, the identification signal communicated between camera A and flash B is not limited to light, and for example, infrared rays or ultrasonic waves may be used.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a camera and a wireless flash to which the present invention is applied, viewed from the back cover side.

FIG. 2 is a front view of the same wireless flash.

FIG. 3 is a perspective view of a stand for the wireless flash.

FIG. 4 is a block diagram showing the internal configuration of the camera.

FIG. 5 is a block diagram showing the internal configuration of the wireless flash.

FIG. 6 is a diagram showing a light emission pattern of a display section of a wireless flash.

FIG. 7 is a circuit diagram of a light receiving section of a wireless flash.

FIG. 8 is a time chart showing the operation in the wireless flash emission mode according to the present embodiment.

FIG. 9 is a time chart in the same test light emission mode.

FIG. 10 is a flowchart showing operations on the camera side.

FIG. 11 is a flowchart similar to the above.

[Figure 12] Subroutine “Completion Check 2” as above
3 is a flowchart showing the operation of FIG.

FIG. 13 is a flowchart showing communication between the camera and the wireless flash.

FIG. 14 is a flowchart showing the operation of the interrupt processing routine "INTWL" on the wireless flash side.

FIG. 15 is a flowchart similar to the above.

FIG. 16 is a flowchart showing operations on the camera side.

[Figure 17] Subroutine “flash communication” same as above
3 is a flowchart showing the operation of FIG.

FIG. 18 is a flowchart when the ranging switch S1 is turned on.

FIG. 19 is a flowchart showing the operation of “exposure calculation”.

FIG. 20 is a flowchart when the release switch S2 is turned on.

FIG. 21 is a flowchart showing the “exposure” operation.

FIG. 22 is a flowchart showing the operation of the interrupt processing routine “INTFL”.

FIG. 23 is a flowchart of a "test light emission" routine for outputting a signal for performing a test light emission.

FIG. 24 is a flowchart of the “Completion Check 1” routine.

FIG. 25 is a time chart in a test light emission mode according to another embodiment.

[Explanation of symbols]

A Camera B Wireless flash MC1 Camera built-in microcomputer MC2 Wireless flash built-in microcomputer 2 Mode change button 4 Camera built-in flash

Claims (2)

[Claims] 1. A dimmable main flash that is built in or connected to the camera and outputs a light emission control signal, and a dimmable main flash that is used without being connected to the camera and that receives the control signal and emits light wirelessly. In a camera system capable of wireless flash photography, the main flash is equipped with an output for emitting an identification signal for identifying that the signal is for wireless flash photography before the start of one-shot movement of the shutter. wireless flash photography, characterized in that the sub-flash has an identification means that receives the identification signal, identifies whether the identification signal is correct, and shifts to wireless flash emission operation. possible camera system. 2. The camera system capable of wireless flash photography according to claim 1, wherein the identification signal has a plurality of forms.