JPH0593944A - Camera and system consisting of external stroboscope non-connected with camera - Google Patents

Abstract

PURPOSE:To provide a camera and a system consisting of a stroboscope non- connected with the camera where an external stroboscope appropriately emits light by transmitting information on the light emitting timing and the emitted light quantity of the external stroboscope by the use of the emitted light other than emitted light for exposure of the camera. CONSTITUTION:Each information such as film sensitivity information 2, F number information at the time of emitting light 3, object distance information and time information 4 from reference timing to light emission in the camera 1 is inputted in a preliminary light emitting interval arithmetic means 5, and converted into the time of the light emitting interval of the preliminary light emission according to a specified system, then, a light emitting member 8 is allowed to emit light plural times at the light emitting intervals by a preliminary light emission control means 6. In the external stroboscope 9, a light receiving means 10 receives preliminary emitted light or the reflected light and each information is detected by a light quantity control information detecting means 11 and a light emitting timing detecting means 12, so that appropriate light emission of the stroboscope is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system composed of a camera and a strobe for transmitting information by utilizing pre-emission from a camera or an external strobe and controlling light emission for exposure of the external strobe.

[0002]

2. Description of the Related Art Generally, there is a slave type small strobe that emits light in synchronism with strobe light emitted by a camera as an auxiliary lighting device for taking a picture with a camera or the like. This strobe is used to improve the effect of expressing a photograph by devising the lighting on the subject and to fill the shortage of the built-in strobe light amount of the camera.

[0003]

However, since the above-mentioned conventional slave type strobe is not connected to the camera by a cord or the like, the arrangement is simple, but it is synchronized with the strobe projection of the camera. , It is difficult to obtain a photograph with proper exposure because it only emits light with a preset guide (G) number.

Therefore, it is possible to change the light amount of the slave strobe according to the F number of the lens mounted on the camera and the distance between the strobe and the subject, but the operation becomes complicated and not easy.

Further, it has been impossible to illuminate only the slave type strobe and not the strobe on the camera side.

For this reason, it has been difficult for anyone other than those who have mastered the technique to take effective photographs by devising the lighting of the subject. Further, a system in which the slave strobe is connected to the camera body by a synchro cable and exchanges exposure information may impair the portability which is a characteristic of a compact camera.

Therefore, the present invention uses the light emission other than the light emission during the exposure of the camera, and the light emission timing of the external strobe and
An object of the present invention is to provide a system composed of a camera and a strobe which is not connected to the camera, by transmitting information for controlling the light emission amount of the external strobe so that the external strobe appropriately emits light by a release operation.

[0008]

In order to achieve the above-mentioned object, the present invention provides a pre-light emitting means capable of continuously emitting a plurality of pre-flashes, and information on the light emission amount and light emission timing of an external strobe which is not connected. The light emission information storage means for storing, a calculation means for calculating an interval between a plurality of pre-light emission based on the information on the light emission amount read from the light emission information means, a pre-light emission interval calculated by the operation means and the Provided is a camera including a light emission control unit that performs pre-light emission based on the light emission timing of an external strobe and controls the light emission amount and light emission timing of the external strobe before starting exposure.

Further, regarding the light receiving means for receiving the pre-light emitted by the camera, photoelectrically converting the same to output a control signal, and information relating to the light emission amount and light emission timing based on the control signal. There is provided a system including an external strobe which is not connected to the camera and which includes a detection means for detecting information and a light emission control means for controlling the light emission amount and the light emission timing of the external strobe based on the detection means.

[0010]

According to the system of the present invention, which comprises a camera and a strobe (external strobe) not connected to the camera, pre-light emission is performed a plurality of times at predetermined intervals between the camera and the external strobe to control the light emission timing and the light emission amount. Information is transmitted.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a schematic block diagram of the first embodiment of the present invention.

Film sensitivity information (hereinafter referred to as S
v information) 2 and F number information at the time of light emission, (hereinafter Av information) 3, subject distance information (hereinafter Dv information) 30, and time information from reference timing to light emission (hereinafter t _T information) 4. These are the values obtained from the shutter mechanism of the camera, the characteristics of the lens, and the DX code of the film.

Each of the above-mentioned information is input to the pre-light emission interval calculation means 5 and converted into the time of the light emission interval of the pre-light emission according to a predetermined method described later, and the pre-light emission control means 6 causes the light emitting member 8 to emit the light. Flash multiple times at intervals. Here, the pre-light emission is light emission performed before exposure, and is assumed to be stroboscopic light emission with a small light amount performed by a part of the energy stored in the main capacitor, or light emission with an LED with a large light amount.

Further, in synchronization with the reference timing generated by the reference timing generation means 7 with the start of exposure, the pre-light emission control means 6 causes the light emitting member 8 to emit light.

A light receiving means 10 is provided in the external strobe 9, and when pre-emission (or reflected light from a pre-emission subject) is received, waveform shaping is performed, and based on the signal, light amount control information is obtained. The detection means detects the Sv information and the light amount control information related to the Av information.

When the light emitting timing detecting means 12 detects the light emitting timing from the light receiving means 10, the light emitting control means 13 causes the strobe light emitting member 14 to emit the strobe light based on the light amount control information.

Next, FIG. 2 shows a configuration situation when the above-mentioned first embodiment is used. Prior to photographing, the camera 1 for photographing irradiates the subject 15 with pre-emission according to a predetermined protocol. At that time, the external strobe 9 detects the pre-light emission reflected from the subject 15, decodes necessary information by the protocol, and controls the light emission and the light emission amount in synchronization with the exposure of the camera.

As a result, the photographer can irradiate the subject with the strobe from any direction without performing a complicated operation for properly adjusting the exposure with respect to the external strobe, and the photograph can be taken. The width can be increased.

Regarding the pre-emission used as means for communication from the camera to the strobe of the present invention, the pre-emission for pupil contraction disclosed in Japanese Patent Application No. 01-282708 by the same applicant is also used. May be.

As an example of this, a specific circuit is shown in FIG. According to FIG. 3, the xenon tube 16 and the IGBT (I
Insulated Gate Bipolar Tra
nistors) 17 are connected in series,
A main capacitor 18 is connected to both ends of. I
The GBT is an element capable of flowing a large current by applying a voltage to the gate, and the gate control circuit 20 controls the gate.

In the control method using this circuit, as shown in the flow chart of FIG. 4, first, a high voltage of about 40 V is applied to the gate by the gate control circuit (step S1), and the IG
After turning on BT, a trigger is generated by the trigger generation circuit (step S2). As a result, the xenon tube 16 starts to emit light and waits for the pre-emission time (step S3).
After that, the gate voltage is set to 0 V to stop light emission (step S4).

Therefore, the light amount of the pre-emission is changed by changing the pre-emission time to change the light emission time. The amount of strobe light during exposure can also be controlled with the same circuit. Such pre-light emission is
An element such as a thyristor other than BT may be used. Further, as shown in FIG. 5, ON / OFF of the LED 18 may be controlled by switching the transistor 17.

Next, FIG. 6 shows a time chart of the light emitting operation of the camera and the external strobe.

The camera of the present embodiment is a lens shutter camera, and controls the exposure time and the light emission timing based on the on / off state of the AE switch, which is the reference timing for exposure.

Pre-flashing is performed four times, the interval t ₁ between the first and second shots corresponds to the light amount control information of the strobe, and the interval t _T between the second and third shots is from the reference timing to the flashing. It is time, and the fourth shot is emitted at the same time as the reference timing. By adjusting the reference timing before opening,
The fourth pre-emission does not affect the exposure because it shines before opening.

The external strobe is t from the fourth pre-flash.
_The main light emission is performed after _T, but at this time, the light amount is controlled based on the light amount control information obtained from t ₁ . It is light intensity control information, but from the G number formula,

[0028]

[Equation 1] Taking the logarithm squared both ^{sides, log2GNo 2 = log2FNo 2 + log2d} 2 + log2S (100) - log2S ... (2) ^{Here, Gv = log2GNo 2, Av =} log2FNo 2, Dv = log2d 2 Sv = log2S, If Sv (100) = log2S (100) (3), then Gv = Au + Dv + Sv (100) -Sv (4). The Dv value here is the distance from the camera to the subject, but it is considered that the distance between the external strobe and the subject is usually not so large, so the Gv value obtained by the equation (4) is converted to t ₁ time and sent. ..

Any method may be used as the method for converting to t ₁ , but in this embodiment, in order to obtain easily, as shown in Table 1, the light amounts of Sv, Dv, Av, and Gv are shown. A standard table in which control information is associated with time data of pre-light emission intervals is used.

[0030]

[Table 1] As a result, Av when the camera emits light and D of the subject distance
By converting v and the used film Sv according to the standard table of Table 1 and calculating the equation (4), the time t ₁ corresponding to the appropriate Gv value is obtained. For example, Av = 4 (F number =
4.0), Dv = 3 (2.8 m), Sv = 7 (ISo
At the time of 400), t ₁ = 1.3 + 0.6 + 0.3-0.5 = 1.7 ms.

At this time t _T , in order to reduce the release time lag caused by making the interval between the second and third shots equal to the time t _T , the interval between the second and third shots is divided by an integer.
Alternatively, a logarithmically compressed value may be used.

FIG. 7 shows a flowchart (REL) of the operation of the camera after the release according to the present invention.

First, distance measurement and photometry are performed (step S1).
0), and based on the distance measurement result, the lens extension amount (step S11) and the Dv value are calculated (step S1).
2).

Enter the DX code (step S13),
The Sv value is obtained (step S14), and the second is calculated from this and the photometric value (step S15). Further, the time t _T until light emission (step S16) and the Av value when the light is opened are obtained (step S17).

These calculation methods are described in JP-A-02-032.
It can be easily calculated by the method described in Japanese Patent Publication No. 194.

The respective Av values and Dv obtained as described above
The value and the Sv value are adjusted to the standard table of Table 1 as described above, and t ₁ = Av + Dv + Sv (100) −Sv is calculated to obtain the time t ₁ (step S18).

Further, in the flowchart, after the lens is extended (step S19), the first pre-flash is performed (step S20), waits for t ₁ hour (step S21), and the second pre-flash (step S22). ), And wait for t _T time (step S23), and the third pre-light emission is performed (step S24).

Next, the shutter control is started (step S2
5) Wait for the AE switch to turn off (step S2)
6). When the AE switch is turned off (YES), the fourth pre-flash is performed to send the reference timing (step S27), and the reproduction at the time is started.

Whether the time until light emission has elapsed (step S
28) A check is performed, and when the time until the light emission is reached (YES), it is checked whether or not the strobe is in the off mode (step S29), and in the modes other than the off mode, the main light emission is performed (step S30).

Next, whether seconds have passed (step S31)
A check is made, and when the time reaches the second time, the shutter control is ended (step S32) and after one frame is wound up in step S33), the process returns and the release process is ended.

Next, the operation on the strobe side will be described with reference to the flowchart of FIG.

First, the normal strobe side determines whether or not the pre-light emission from the camera is emitted (step S4).
0).

When the pre-flash is received, the timer is started (step S41), and the second pre-flash is waited (step S42). When the second flash is emitted (YE).
S) The count value between the first shot and the second shot is put into t ₁ (step S43).

Next, the range of t ₁ is judged (step S44). If 80 ms ≦ t ₁ ≦ 3 ms, it is normal, but otherwise, it is judged to be abnormal, and the process returns to step S40. Since the value corresponds to the light amount Gv of t ₁ , in a normal state, after the timer is started (step S45), the strobe light emission time is obtained from t ₁ (step S46).

Therefore, if the circuit of the light emitting portion on the external strobe side has the configuration shown in FIG. 3, the light quantity can be easily controlled by having a table of the time t ₁ and the light emitting time.

Further, it is checked whether or not the third pre-flash is emitted (step S47), and when the third flash is emitted (YES), the count value between the second and third shots is t. Enter ₁ (step S48).

Here, the interval t _T between the second and third shots is 1 ms.
It is checked whether or not it is within the range of ≤t _T ≤40 ms (step S49), and if abnormal, the process returns to step S40.

It is checked whether or not the fourth pre-emission, which is the next reference timing, is emitted (step S5).
0), when pre-flashing (YES), time t until flashing
Wait for _T (step S51), start main flash emission (step S52), and wait for light emission time (step S5).
3), the light emission is stopped (step S54), and step S4
Return to 0.

In this embodiment, when the camera side is set to the strobe off mode and an image is taken, the camera side does not perform the main flash, but only the external strobe emits light, which is not possible with the conventional slave strobe. Become.

Next, as a second embodiment, a system having a photometry circuit on the strobe side will be described. In the first embodiment, it is assumed that the distance between the camera and the subject and the distance between the external strobe and the subject are substantially equal, but if an accurate exposure is attempted, it will still be a problem.

The difference from the first embodiment is the meaning of t ₁ , and in the second embodiment, t ₁ is Av + Sv (100) −.
As information corresponding to Sv, information excluding information on distance is transmitted to the strobe.

Such an external strobe is provided with an integrating circuit shown in FIG.

This integrating circuit includes operational amplifiers OP1 and SB.
The gate is switched from ON to OFF at the start of light emission by the integration circuit 25 including C, a capacitor, and an integration start gate, and integration is started. Further, the judgment value is calculated from the light amount control information t ₁ 23 from the camera, or a table is referred to, the value is converted into a judgment voltage by the D / A circuit, and is compared by the integral output comparator OP2.

The output of the integrator circuit rises due to the amount of light reflected from the strobe subject, and when the judgment voltage is exceeded, O
The output of P2 is inverted, and the light emission stop circuit stops light emission. An external strobe can be controlled with an appropriate amount of light by forming a determination voltage at t ₁ corresponding to the ISO sensitivity of the camera and the diaphragm and performing integration with the amount of light that includes distance information of reflected light from the subject.

However, when both the external strobe and the built-in strobe are fired, if the external strobe and the built-in strobe are fired at the same time, the amount of light cannot be adjusted accurately on the external strobe side, so as shown in FIG. The main flash of is emitted at the timing after the external flash fires. That is, the built-in flash of the camera is turned on after the time t _s, which is the time t _T from the sent reference timing to the light emission of the external strobe, plus the longest light emission time of the external strobe, to the external strobe. By doing so, the dimming of the external strobe is accurately performed.

Further, in the first embodiment, the detection of the pre-light emission is performed by the reflected light from the subject, but in the case of the second embodiment,
If the external strobe is within the irradiation angle of the strobe on the camera side, the pre-flash may be directly received.

FIG. 10 shows a situation when the camera and strobe system of the third embodiment are used. In the first and second embodiments, the communication is one-way communication from the camera to the strobe, and the camera releases depending on the direction of the external strobe.
Although it is possible that the external strobe does not emit light, the third embodiment proposes a system that surely emits the external strobe when exposure is performed by performing bidirectional communication.

The external strobe has a built-in remote control function, and information is sent from the external strobe to the camera by the remote control. It is possible to pre-flash the external strobe to convey information to the camera, but as a case of using the external strobe a lot, there is portrait shooting.In this case, if the external strobe fires before the exposure, the subject will be surprised. Use a remote control with infrared light that is invisible because it is likely to ruin portrait photography, such as moving your eyes or carelessly moving your line of sight.

As for such a remote control method, a remote control function for sending codes 0 to 7 to the camera is built in the external strobe by the method described in Japanese Patent Application No. 02-205556 by the same applicant. And These codes are switched by the mode switch of the external strobe, the remote switch's release switch starts transmission of the remote control, and the camera side changes the pre-flashing method according to the received code to obtain the necessary information. Sends to a flash and fires an external flash in synchronization with exposure.

Table 2 summarizes the codes of the remote controller of this embodiment, the corresponding pre-emission intervals of the camera, and the manner and characteristics of main light emission, and FIG. 11 shows a time chart of each code.

[0061]

[Table 2] Here, the code 0 is a value that corresponds to Av-Sv + Dv in the time t ₁ of the first shot and the second shot in the case of two pre-flashes, and the external strobe emits light at the same time as the main flash of the camera.

The pre-flashes of the codes 1 and 2 are four shots, and the time t ₁ of the first shot and the second shot is Av-S like the code 0.
It is a value corresponding to v + Dv, and the time t of the second and third shots
_T is the time from the reference timing to light emission, and the fourth shot is the reference timing. Then, the strobe emits light t _T time after the fourth light emission.

However, in Code 1, the camera side also emits main light with one step under, but in Code 2, it does not emit main light.

The pre-emission of codes 3 and 4 is 1 out of 5 shots.
The time t ₁ of the second shot is a value corresponding to Av-Sv, and the distance information Dv is sent at the time t ₂ of the second shot and the third shot, and the time of the third shot and the fourth shot. At t _T , the light is emitted t _T time after the fifth light emission. With code 3, the camera emits main light, and with code 4, it does not. On the strobe side, the distance can be measured or the amount of reflected light can be integrated on the strobe side without using the distance information t ₂ to optimize the exposure.

The codes 5 and 6 are similar to the codes 4 and 5 in terms of t _{1 and} t ₂ , but the under amount of the light amount on the camera side is sent at the time t ₃ of the third and fourth shots.

The under amount also corresponds to t _{3 in} Table 1, and for example, when t ₃ = 0.5 ms, it means that the exposure of the camera is under two steps.

The fourth and fifth shots are at time t _T , and light is emitted after t _T time from the sixth shot. With this code, the underside on the camera side can be supplemented with an external strobe.

Code 7 is a code output when the external strobe is half-pressed, and the camera side turns on the LED in F or sounds PCV to inform the user that communication is normally performed. By this, the user can confirm the communication.

FIG. 12 shows a schematic block diagram of the third embodiment. Differences between the third embodiment and the first embodiment will be described.

In the external strobe of the third embodiment, a mode selecting means is added to change the value of the code "CODE" of the remote control and transmit it to the remote control transmitting circuit.

When the release switch 35 is pressed halfway, the visible light generating means 33 of the spot emits visible light. By pressing the release switch halfway down, the data of code 7 is transmitted from the remote control transmission circuit, and the value of "CODE" is transmitted by the second release.

The transmission signal from the external strobe is received by the remote control receiving circuit 31 on the camera side, and the remote control code "CODE" is detected.
When this "CODE" is "1, 3, 5", the main light emission prohibiting means 29 prohibits the main light emission. Also, "COD
Depending on the value of “E”, the film speed information 2, the F number 3 at the time of light emission, the time information 4 from the reference timing to the light emission, the G number information 27 of the built-in flash, the object distance information 30, and the number of pre-flash intervals The calculation unit 5 calculates the interval and number of pre-light emission, and the pre-light emission control unit 6 causes the light emitting member 8 to pre-light.

When the value of "CODE" is 0 to 6, shutter control is started by the shutter control means 32,
As a result, reference timing is generated from the reference timing generation means 7, and when the value of "CODE" is 1 to 6, pre-light emission is performed at that timing. According to the subject distance information 30, when the distance of the subject is long, the light amount of pre-emission is increased.

In the light quantity control information detecting means of the external strobe, the manner of detection and the information to be detected change depending on the mode.

A third part of the flowchart of FIGS. 13 and 14 is shown.
The main operation | movement (main flow) of the camera of an Example is shown.

First, normally, predetermined display items are displayed (step S60), and camera operation such as exposure, mode change, rewind, etc. is performed (step S62) depending on whether or not the camera is operated (step S61).

Then, the presence or absence of the remote control signal is checked (step S63), and when the remote control signal does not arrive, the predetermined display item of step S60 is displayed. When the remote control signal arrives (step S64), it judges whether the received "CODE" is "7" (step S65) and "CODE".
When is “7” (YES), it is communication confirmation, so PCV
Is sounded (step S66), and the process returns to step S60.

When this "CODE" is other than "7", (N
O), perform processing for exposure.

For this, the distance measurement value, the light measurement value and the DX code are input (step S67), and Dv and Sv are obtained. Further, calculation in seconds (step S68), time t _T until the external strobe emits light is calculated (step S69), and A
The v value is calculated (step S70), the main light emission amount is calculated (step S71), and the pre-emission light amount is calculated (step S72).

When the method for controlling the light quantity of the external strobe is controlled according to the table of the light emission time, as in the first embodiment, the light emission timings of the built-in strobe and the external strobe may be the same, but the second embodiment. In the case of a dimming external strobe as in the example, the time t _T until the external strobe fires
As a result, the time t _s until the light emission of the built-in flash is extended by the light emission time of the external strobe. In the case of code 0, simultaneous light emission occurs, so it is better to use the light emission time table.

After the lens is extended (step S7)
3), the value of "CODE" is determined (step S7).
4). In this judgment, when “CODE” = 0, 1, 2
to t ₁ put a value corresponding to the Av-Sv + Dv (step S79), but "CODE" = 3,4,5,6 time of, to t ₁ Av-Sv (step S75), Dv to t ₂
Put a value corresponding to (step S76), was calculated under the amount of light intensity (step S77) after putting a value corresponding to the under amount of light intensity to t ₃ (step S78).

Depending on the code, the pre-flash causes t
A required value of _{1 to} t ₃ is sent, and when CODE = 0 is not set, t _T time is also sent as a pre-light emission interval (step S8).
1 to step S86). Then, shutter control is started ((step S) S89). Then, the state of the AE switch, which is the reference timing, is determined (step S92),
If it is off (NO), pre-light emission is further performed when "CODE" = 0. The exposure timer is started (step S93). Next, it is determined whether or not the time t _T has elapsed (step S94), and after the time t _{T has} elapsed, "COD
The value of "E" is determined (step S95), and "COD
If E ″ = 0, 2, 4, 6 then main light emission is performed while controlling the light quantity so that it is under one step (step S9).
6). If the external strobe side is also under-one step, it will be appropriate for both strobe lights.

Next, the seconds are checked (step S9
7) When the predetermined time has elapsed, the shutter control is ended (step S98), and one frame is wound (step S9).
9) Return to the normal display loop.

FIG. 15 shows a preflash detection circuit for the external strobe, and FIG. 16 is a time chart showing the output waveform of each circuit of the detection circuit. The output of the light receiving element 43 is logarithmically compressed by the photometric logarithmic compression circuit 38, and the level shift circuit 3
9 to the sample hold circuit 42 via the gate 41. After the remote control transmission, the gate 41 is turned off so that the sample hold circuit 42 latches the luminance before the pre-emission. Since the brightness difference before pre-flashing and during pre-flashing can be sufficiently determined in about 1.5 steps, the level shift circuit shifts the logarithmic compression level by 1.5 steps, and this value is compared with the sample-held value by the comparator 40. This outputs a square wave d.

The timing of turning off the gate of the sample hold may be any time before pre-emission, but here, it is turned on at the start of remote control communication and turned off at the end of remote control transmission.

Next, referring to the flow charts of FIGS. 17 and 18, the operation of the external strobe side of the third embodiment will be described.

When the power is turned on, "CODE" is initialized to "0" (step S111), and it is determined whether or not the mode switch is turned on (step S112). Every time the mode switch is turned on, "CODE" is turned on. Add "1" to "" and return to "0" when it becomes "7".

Next, the charging voltage is checked (step S1
14), charge at less than 330V (step S115),
Charging is stopped at 330 V or higher (step S116).
LED indication that this charging is completed (step S
117).

Then, it is checked whether the release switch provided on the external strobe is half pressed (step S11).
8). Until the switch is pressed halfway (NO), the mode switch process, charge check, and LCD display process are performed. However, when it is pressed halfway (YES), the spot irradiation LED
Is turned on (step S119), and the central position of the strobe light is illuminated. This may be shared by increasing the visible light component of the wavelength of the LED that outputs far-out light for remote control. The red LED is used here because it is easy to obtain a bright brightness with a relatively small current.

Thus, photographing can be performed after confirming the irradiation position of the external strobe.

After the LED is turned on, the remote control is transmitted (step S120). In this case, "CODE" is set to "7" to convey the half-press on the strobe side.

Whether half-press is off (step S121)
Also, the state of the second release further pushed after half-push is checked (step S122), and when half-push is turned off (NO), the spot irradiation LED is turned off.

When the second release is turned on (YES), the spot irradiation LED is turned off (step S124), the charging voltage is checked (step S125), and the charging is stopped (step S126). The sample hold gate is turned on (step S127), remote control transmission is performed (step S128), and the sample hold gate is turned off (step S129) to latch the brightness at the time of remote control transmission.

Further, "1" is added to the number of pre-flashes (step S130), reception of pre-flashes is started (step S131), and information of t ₁ to t ₃ is input according to "CODE" ( Step S132 to Step S13
6).

Then, it is judged whether or not "CODE" is "0" (step S137), and if "CODE" is not 0 (NO), the value of t _T is also input to respond to "CODE". The light amount control value is determined (steps S138 to S143), and light is emitted while controlling the light amount after t _T time from the pre-light emission at the reference timing.

When "CODE" = 0 in step S137 (YES), the light amount control value is determined (step S14).
4), along with the main flash of the camera (step S14)
5) Emit light while controlling the light amount (step S1)
46).

Here, the camera-side under amount used in “CODE” = 5 and 6 in Table 2 is the difference between the required Gv value obtained by the equation (4) and the Gv value of the strobe in the camera. An under-luminance component other than the flash light amount may be added.

When the exposure correction is performed on the camera side, the time t ₁ corresponding to Av-Sv + Dv or Av-Sv can be easily adjusted by adjusting the amount according to the correction amount.

Further, the present invention is not limited to the above-mentioned embodiment, and it is needless to say that various modifications and applications can be made without departing from the scope of the invention.

[0100]

As described in detail above, according to the system including the camera and the strobe of the present invention, information is transmitted from the camera to an external strobe that is mechanically independent from the camera by using pre-flash. By doing so, the photographer can perform daylighting photography from any direction with a simple operation.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of a first embodiment of the present invention.

FIG. 2 is a diagram showing a situation in which the camera and strobe system of the first embodiment are used.

FIG. 3 is a diagram showing a specific circuit of a communication unit from a camera to a strobe.

FIG. 4 is a flowchart showing a gate control operation in the gate control circuit.

FIG. 5 is a diagram showing switching of transistors
It is a circuit diagram which controls ON / OFF of LED.

FIG. 6 is a time chart showing a light emitting operation of a camera and an external strobe.

FIG. 7 is a flowchart showing a release operation (REL) on the camera side.

FIG. 8 is a flowchart showing an operation on the strobe side.

FIG. 9 is a circuit diagram showing an integrating circuit provided in an external strobe.

FIG. 10 is a diagram showing a situation in which the camera and strobe system of the third embodiment are used.

FIG. 11 is a time chart showing an output waveform of each code for pre-emission of the camera.

FIG. 12 is a diagram showing a schematic configuration of a third embodiment.

FIG. 13 is the first half of a flowchart showing the main operation (main flow) of the camera of the third embodiment.

FIG. 14 is the second half of the flowchart showing the main operation (main flow) of the camera of the third embodiment.

FIG. 15 is a circuit diagram showing a circuit section for detecting pre-emission provided in an external strobe.

16 is a time chart showing an output waveform of each circuit forming the detection circuit unit of FIG.

FIG. 17 is a first half portion of a flowchart showing the operation on the external strobe side of the third embodiment.

FIG. 18 is the second half of the flowchart showing the operation on the external strobe side in the third embodiment.

[Explanation of symbols]

1 ... Camera, 2 ... Film sensitivity information, 3 ... F number information, 4 ... Time information from reference timing to light emission, 5 ...
Pre-light emission interval calculation means, 6 ... Pre-light emission control means, 7 ... Reference timing generation means, 8 ... Light emitting member, 9 ... External strobe, 10 ... Light receiving means, 12 ... Light emission timing detection means,
13 ... Light emission control means, 14 ... Strobe light emitting member, 15 ...
Subject, 30 ... Subject distance information.

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[Procedure amendment]

[Submission date] August 20, 1991

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0015

[Correction method] Change

[Correction content]

Each of the above-mentioned information is input to the pre-light emission interval calculation means 5 and converted into the time of the light emission interval of the pre-light emission according to a predetermined method described later, and the pre-light emission control means 6 causes the light emitting member 8 to emit the light. Flash multiple times at intervals. Herein, the pre-emission is a light emission performed in the exposure previously, small strobe light emission or the amount of light is performed from a portion of the stored energy of the main capacitor, it is assumed that light emission due to the amount of the large LED ..

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0028

[Correction method] Change

[Correction content]

[0028]

[Equation 1]Square both sides and take the logarithm, log2GNo^Two= Log2FNo^Two 
 + Log2d^Two+ Log2S (100) -log2
S ... (2) where Gv; log2GNo^Two, Av = log2FNo^Two, D
v = log2d^Two  Sv = log2S, Sv (100) = log2S
If (100) ... (3), then Gv = Au + Dv + Sv (100) -Sv (4). Dv value here is the distance from the camera to the subject
However, the distance between the external flash and the subject is usually not very different.
Since the Gv value obtained by the equation (4) is t,₁Time
Convert and send in between.

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0037

[Correction method] Change

[Correction content]

Next, the shutter control is started (step S2
5), which is the standard of the exposure time, and from on before exposure
It waits until it is turned off (step S26). When the AE switch is turned off (YES), the fourth pre-flash is performed to send the reference timing (step S27), and the reproduction at the time is started.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0064

[Correction method] Change

[Correction content]

The pre-light emission of the codes 3 and 4 is 5 shots.
The time t ₁ of the second shot is a value corresponding to Av-Sv, and the distance information Dv is sent at the time t ₂ of the second shot and the third shot, and the time of the third shot and the fourth shot. At t _T , light is emitted t _T time after the fifth light emission. With code 3, the camera emits main light, and with code 4, it does not. On the strobe side, the distance can be measured or the reflected light amount can be integrated on the strobe side without using the distance information t ₂ to optimize the exposure.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0077

[Correction method] Change

[Correction content]

Then, the presence or absence of the remote control signal is checked (step S63), and when the remote control signal does not arrive, the predetermined display item of step S60 is displayed. However , when the remote control signal arrives (step S64), the received "COD
It is determined whether "E" is "7" (step S65), and "CO"
If "DE" is "7" (YES), it means the communication is confirmed.
Sound PCV (step S66) and step S60
Return to.

Claims (2)

[Claims] 1. A pre-light emitting means capable of continuously emitting a plurality of pre-flashes, a light emission information storage means for storing information on a light emission amount and a light emission timing of an external flash which is not connected, and read from the light emission storage information means. Based on the information on the emitted light amount, the calculating means for calculating the interval between the plurality of pre-flashes, and the start of the exposure based on the pre-flash interval calculated by the calculating means and the light emission timing of the external strobe. A camera comprising: a light emission control unit that performs pre-light emission in advance to control a light emission amount and a light emission timing of the external strobe. 2. A light receiving means for receiving pre-light emitted by the camera according to claim 1, photoelectrically converting the light, and outputting a control signal, and information relating to the light emission amount and light emission timing based on the control signal. A system comprising an external strobe that is not connected to a camera, the system including a detection unit that detects information related to the camera, and a light emission control unit that controls the light emission amount and the light emission timing of the external strobe based on the detection unit.