JP2909094B2 - TTL dimmable camera and strobe device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Application of the Invention) The present invention relates to a camera capable of so-called TTL dimming, in which a strobe light incident through a photographing lens is directly measured or a photometric integration of a reflected light thereof, and a camera mounted on the camera. The present invention relates to an improvement of a strobe device.

BACKGROUND OF THE INVENTION In conventional systems of this type, in many cases the flash dimming level is automatically calculated according to the film speed, the selected aperture and the tuned shutter speed, etc.
It was unique. This produces very good results for some subjects (eg, an 18% gray reflector), but is unsatisfactory for others. For example, it has been a common experience that a white subject does not appear white or a black subject does not appear black. In particular, it was remarkable in photographing with a reversal film in which correction printing was difficult.

In order to solve the above-mentioned drawbacks, there is known a system which can set a correction value indicating a variable amount of a strobe light control level independently of an exposure level determined by ordinary light.

Although this method can certainly reflect the intention of the photographer, it has the following disadvantages.

In other words, there is no problem when used in combination with a strobe device having means for setting a correction value representing a variable amount of the flash light control level and a camera having means for changing the light control level according to the correction value. Since the system described above has recently been realized, there is a possibility that it will be used in combination with a strobe device with a means for setting the correction value and a camera without means for changing the dimming level. Can also be considered.

In such a case, despite the setting of the correction value and the display accompanying the setting on the strobe device side, the dimming correction operation is not performed during the actual photographing, which confuses the user. .

(Object of the Invention) It is an object of the present invention to solve the above-mentioned problems and to provide a TTL light-controllable camera and a strobe device that do not give a user a false recognition as if performing a light control correction operation. It is.

(Characteristics of the Invention) In order to achieve the above object, the present invention provides a determining means for determining whether or not a mounted flash device is a flash device capable of setting a correction value representing a variable amount of a flash dimming level; A variable unit for changing the strobe light control level in accordance with the transmitted correction value; and a correction value set in the strobe device when the determination unit determines that the device is a strobe device capable of setting a correction value. Information is transmitted to the variable means, and when the determination means determines that the electronic flash device is not a strobe device for which a correction value cannot be set, correction value information indicating that the correction value is "0" is transmitted to the variable means. And a dimming operation control means.

Further, a correction value setting means for setting a correction value representing a variable amount of a flash light control level, an output means for outputting correction value information set by the correction value setting means, Determining means for determining whether the camera is operable; and prohibiting means for prohibiting the setting of the correction value when the determining means determines that the camera is not capable of changing the dimming level. It has a configuration with.

FIG. 1 is a block diagram showing an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a strobe device, which is a microcomputer
2, a setting unit 3 for setting a correction amount representing a variable amount of the flash light control level, a display unit 4 for displaying the correction amount, etc., a charge detection circuit
5, a trigger circuit 6 and a dimming circuit 7 are provided. Reference numeral 11 denotes a camera body, which includes a microcomputer 12, a photometry circuit 13, an integration circuit 14, a D / A converter 15, a comparison circuit 16, a setting unit 17 for setting a projection mode such as a fully automatic mode, and information on a shooting mode and the like. The display unit 18 includes, for example, an LCD for displaying. The strobe device 1 and the camera body 11 exchange signals through terminals SI, SO, SC, C, TRI, and STOP.

The port C of the microcomputer 12 has a terminal C, the port E has a terminal TRI, the port D has a D / A converter 15, the port F has an integrating circuit 14, the port G has a display section 18, The setting unit 17 is connected to the port H.

The trigger circuit 6 and the dimming circuit 7 are the same as those used in a conventional flash circuit. The charge completion detection circuit 5 monitors the voltage of the main capacitor in the strobe device 1, and when the voltage becomes equal to or higher than a predetermined voltage at which the Xe tube can emit light, a charge completion signal is sent to the camera body 11 via the terminal C. Is output.

The setting section 3 has two keys 3a, 3 as shown in FIG.
b (hereinafter referred to as + SW, -SW), and the correction amount is controlled by this as described above. The display unit 4 is, for example,
It is constituted by an LCD. Here, if, for example, + 1F is displayed as shown in FIG. 2, it means that the light control amount is over one step.

As will be described later, an SPD is used for a sensor in the photometric circuit 13, and the circuit has an amplification function. Light emitted from the strobe device 1 is reflected on the film surface through the lens, and the reflected light is received by the SPD.

The integration circuit 14 starts integration of the voltage V _IN from the photometry circuit 13 at the same time as the START signal is input from the port F of the microcomputer 12, and outputs the voltage IN2.

The comparison circuit 16 compares the voltage IN1 from the D / A converter 15 with the voltage IN2 from the integration circuit 14, and if IN1> IN2, the terminal S
A low-level signal is output to the dimming circuit 7 of the strobe device 1 via the TOP, and a high-level signal serving as a timing signal for stopping the strobe emission if IN1 <IN2.

The D / A converter 15 converts the input digital value D into a voltage (analog voltage) IN1 as described above.

FIG. 3 shows a program incorporated in the microcomputer 12 when the camera body 11 is a camera with a variable light control level, and FIG. 4 shows a program when the camera is not a camera with a variable light control level. When the strobe device 1 is a strobe device having the setting unit 3 for setting a correction value (in the case of a configuration as shown in FIG. 1), a program incorporated in the microcomputer 2 is shown in FIG. FIG. 6 shows a program of the microcomputer 2 assuming a strobe device not having the setting unit 3 in FIG.

In the above configuration, serial communication between the strobe device 1 and the camera body 11 via the terminals SC, SI, and SO is performed as follows.

In the microcomputer 12 in the camera body 11, serial data input from the flash device 1 is stored in a serial register SIR, and serial data output from the camera body 11 to the flash device 1 is stored in a serial register SA. And Conversely, the microcomputer 2 of the strobe device 1
It is assumed that the serial data input from the camera body 11 is stored in the serial register SR, and the serial data output to the camera body 11 is stored in the serial register CA.

A serial clock signal is emitted from the camera body 11,
Synchronous transmission of 8-bit serial data is performed. The format is shown in FIG. 8, and the communication timing is shown in FIG.

First, a compatibility communication request (DR) is transmitted from the camera body 11 to the strobe device 1, and at the same time, serial data is sent from the strobe device 1 to the camera body 11, and this serial data is particularly defined as can be seen from FIG. It has not been.

Next, dimming level operation mode data (CC) is communicated from the camera body 11 to the strobe device 1, and at the same time, serial data (SH) is sent from the strobe device 1 to the camera body 11, as shown in FIG. The correction amount is defined as follows.

The above two 8-bit communication groups are repeated thereafter (No. 9).
See figure).

Here, combinations of compatibility between the strobe device 1 and the camera body 11 are classified into cases I to IV as shown in FIG.
Regarding a strobe device capable of setting a correction amount representing a variable amount of a strobe light control level, it is assumed that a correction amount “−1” is set in advance before serial communication is performed.
Each case is described below.

<1> Case I First, the operation of the microcomputer 12 in the camera body 11 will be described with reference to FIG.

 This program is started from step 451.

In step 451, an initialization operation is performed. This operation will not be described in detail since neither step 452 nor the following is a feature of the present embodiment.

 Therefore, description will be made from step 453.

In step 453, “1” is substituted into the register SA in preparation for the next communication to the flash device 1, and the process proceeds to step 454.

At step 454, register S with the serial clock
Output the value of A to the flash unit 1 from the terminal SO, and
Go to 55.

In step 455, 81H (H: hexadecimal) indicating that the dimming level is variable is substituted into the register SA, and the process proceeds to step 456.

At step 456, register S with the serial clock
Output the value of A to the flash unit 1 from the terminal SO, and
Go to 57.

At step 457, register S
It is determined whether or not the value stored in the IR is FFH. At this time, since the value of the register SIR is F1H (= −1), the flow branches to step 458.

In step 458, the value of bit0 of register SIR (the value of b _o of the serial data SH of FIG. 8) is "1" or not, that is the strobe device 1 determines whether the correction value can be set ,
At this time, since the value of the register SIR is F1H, the flow branches to step 459.

At step 459, 4b is set for register SIR (8 bits).
The result of subtracting "16" from the value "15" shifted to the right of it (-
After substituting 1) into the correction value variable S, step 452 is performed again.
Return to

 Thereafter, the above operation is repeated.

Next, the operation of the microcomputer 2 of the flash device 1 will be described with reference to FIGS.

FIG. 5 shows the main operation of this program.

When power is supplied to the strobe device 1, the program is started from step 501.

In step 501, an initialization operation (details are omitted) is performed, and the process proceeds to step 502.

In step 502, “1” is set for a variable MODE indicating whether or not the mode is the correction value setting mode, “0” is set for a variable S indicating the correction value, and F
Is initialized by substituting “0” into the register CA and FFH into the register CA.

In step 503, it is determined whether MODE = 1 or not. In this case, since it is "1", the flow proceeds to step 504.

In step 504, the SW operation of the setting unit 3 is performed, and a certain correction value variable S is set. Here, as described above, S
Assuming that -1 has been set, the process proceeds to step 505.

In step 505, a process unrelated to the description of the present embodiment is performed, and the process proceeds to step 503 again.

After that, while MODE = 1, this program will
Repeat 503 → 504 → 505 → 503.

Here, a value other than “1” is not substituted for the variable MODE in the main routine shown in FIG. 5, but may be rewritten to another value in the communication processing program shown in FIG. . This communication processing program will be described.

When an interrupt of serial communication (first time) occurs from the camera body 11, this program interrupts the main program process and starts the process from step 401.

In step 401, the camera body 1
It is determined whether or not the value of bit 7 of the register SR (= 1) storing the data from 1 is "1" (for distinguishing between data CC and DR in FIG. 8). Here, since bit 7 is “0”, step 402
Branch to

In step 402, it is determined whether the value of the register SR is “1”. Since the value of the register SR is "1" at this time, the flow branches to step 403.

In step 403, “1” is set in the flag F, and the process proceeds to step 404.

In step 404, the value of the correction value variable S (FFH [8 bit]) defined in the main program is shifted left by 4 bits (to F0H) and "1" is added (to F1H). Assign the value to register CA. This register CA is
The data is output to the camera body 11 as serial data at the next serial communication.

When a serial communication (second time) interrupt occurs again from the camera body 11, the program interrupts the main program process and starts the process from step 401.

In step 401, the camera body 1
It is determined whether or not the value of bit ₇ of the register SR (81H) storing the data from 1 (the value of b7 of the serial data SH in FIG. 8) is “1”. Here, since bit 7 is “1”, step 411
Branch to

In step 411, it is determined whether the value of the flag F is "1". Since the flag F is "1" in the first communication, the process branches to step 412.

In step 412, a logical sum operation is performed between the register SR (81H) and “1”, the result (= 1) is substituted for a variable MODE, “0” is substituted for a register CA, and the process proceeds to step 422. move on.

This register CA is output to the camera body 11 as serial data at the next serial communication.

 At step 422, the flag F is set to "0".

As described above, the communication program ends and returns, and resumes processing from the position of the main program that was interrupted.

FIG. 11 shows the state of serial communication in case I.

<2> Case II First, the operation of the microcomputer 12 of the camera body 11 will be described with reference to FIG.

In step 453, “1” is substituted for the register SA, and the process proceeds to step 454.

At step 454, register S with the serial clock
The value of A is output from the terminal SO to the strobe device 1, and step 4
Go to 55.

At step 455, 81H (H: hexadecimal) is assigned to the register SA, and the process proceeds to step 456.

At step 456, register S with the serial clock
Output the value of A to the flash unit 1 from the terminal SO, and
Go to 57.

At step 457, register S
It is determined whether or not the value stored in the IR is FFH. At this time, the value of the register SIR is F1H.

At step 458, it is determined whether or not the value of bit 0 of the register SIR is “1”. Since the value of the register SIR is “0”,
Branch to step 460.

At step 460, the variable “S” representing the correction value is set to “0”.
After that, the process returns to step 452 again.

 Thereafter, the above operation is repeated.

Next, the operation of the microcomputer 2 of the flash device 1 will be described with reference to FIG.

FIG. 7A shows the main operation of the program.

When power is supplied to the strobe device 1, the program is started from step 551.

In step 551, an initialization operation (details are omitted) is performed, and the flow advances to step 552.

At step 552, “0” is set to the flag F and the register CA
After the initialization by substituting FFH into, the process proceeds to step 553.

In step 553, other processing unrelated to the description of the present embodiment is performed, and the process proceeds to step 553 again, and thereafter, this is repeated.

The communication processing program will be described with reference to FIG.

When a serial communication (first time) interrupt occurs from the camera body 11, the program interrupts the main program processing and starts processing from step 601.

In step 601, camera body 1
It is determined whether the value of bit 7 of the register SR (= 1) storing the data from 1 is "1". Here, since bit 7 is “0”, the flow branches to step 602.

In step 602, it is determined whether the value of the register SR is "1". Since the register SR is “1”, the flow branches to step 603.

In step 603, “1” is set in the flag F, and the process proceeds to step 604.

In step 604, “0” is substituted for the register CA.
This register CA is output to the camera body 11 as serial data at the next serial communication.

As described above, the communication program ends and returns, and starts processing from the position of the main program that was interrupted earlier.

When a serial communication (second time) interrupt occurs again from the camera body 11, the program interrupts the main program processing and starts the processing from step 601.

In step 601, camera body 1
From 1, it is determined whether the value of bit 7 of the register SR (81H) in which the data is stored is “1”. Here, since bit 7 is “1”, the flow branches to step 621.

In step 621, it is determined whether the value of the flag F is "1". Since the flag F is "1" in the first communication, the process branches to step 622.

In step 622, “0” is substituted for the register CA, and the process proceeds to step 612.

This register CA is output to the camera body 11 as serial data at the next serial communication.

 At step 612, “0” is set to the flag F.

As described above, the communication program ends and returns, and resumes processing from the position of the main program that was interrupted.

The state of serial communication in case II is also shown in FIG.

<3> Case III First, the operation of the microcomputer 12 of the camera will be described with reference to FIG.

 The program is started from step 701.

In step 701, an initialization operation is performed. Since this operation is not a feature of the present embodiment together with step 702, it will not be described in detail.

 Therefore, description will be made from step 703.

In step 703, “1” is substituted for the register SA, and the process proceeds to step 704.

At step 704, register S
The value of A is output from the terminal SO to the strobe device 1, and step 7
Go to 05.

In step 705, 80H is substituted for the register SA, and the flow advances to step 706.

At step 706, register S
After outputting the value of A from the terminal SO to the strobe device 11, the process returns to step 452 again, and the above operation is repeated.

Next, the operation of the microcomputer 2 of the flash device 1 will be described with reference to FIGS.

When power is supplied to the strobe device 1, the program starts from step 501. Note that, while MODE = 1, this program repeats steps → 503 → 504 → 505 → 503 as described above.

On the other hand, when serial communication is performed between the camera body and the flash device, the value of the above-mentioned variable MODE becomes "0" (the description will be given later in a communication program).

Therefore, after serial communication, in step 503, step 5
Branch to 11.

In step 511, “0” is substituted for the correction value variable S,
Proceed to step 512.

In step 512, the number representing the correction value S of the display unit 4 is turned off (FIG. 12 (a) → FIG. 12 (b)).
This indicates that the mode is not the light adjustment correction mode, and the process proceeds to step 513.

In step 513, the operation of + SW and -SW of the operation member 3 is prohibited, and the process proceeds to step 505.

The operation of each step shown in FIG. 6 is performed for the communication processing program, which is almost the same as in the case I described above.
The contents of register SR in step 412 are changed from "81H to 80H"
Therefore, other processing is omitted.

When the above communication program ends, the program returns to the position of the main program in FIG. 5 where the program was interrupted, and the subsequent processing is restarted.

Even in the case of serial communication in case III, the first
Shown in Figure 1.

<4> Case IV The operation of the microcomputer 12 of the camera is performed in steps 701 to 706 in FIG. 4. However, since this is the same as the case III described above, the details are omitted.

The operation of the microcomputer 2 of the strobe device 1 is as follows: Steps 551 to 553, Steps 601 to 604, and Steps 611, 612, 621, and 622 of FIGS.
Is performed, but this is the same as in the case II described above, so that the details are omitted.

Even in the case of serial communication in Case IV,
Figure 11 shows.

(Modification) In the present embodiment, in the flash device 1 having no correction value setting unit, the communication data SH to that effect is held in the microcomputer 2 and a flash dimming level enabling operation is performed. In the case of Camera 11 that cannot perform
Although the description is being made assuming that the communication data CC is held in the memory 12, in the case where the means for setting the correction value and the means for varying the dimming level are not individually provided, Some communication data to that effect is not held, so determination in such a case (determination as to whether or not there is a means for setting a correction value and a means for varying the dimming level).
Is configured such that, for example, when communication for determination cannot be performed, the determination is made.

(Effect of the Invention) As described above, according to the first aspect of the present invention, when it is determined that the attached flash device is a flash device for which a correction value cannot be set, the flash dimming level is not adjusted. Since the correction value representing the variable amount is set to "0", it is possible to provide a TTL dimmable camera that does not give the user a false recognition as if performing a dimming correction operation.

According to the second aspect of the present invention, when it is determined that the mounted camera is not a camera capable of changing the light control level, the correction value indicating the variable amount of the flash light control level is set. Since the prohibition is provided, it is possible to provide a strobe device that does not give a user an erroneous recognition of performing a flash control operation.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing details of a display unit and an operation unit shown in FIG. 1, and FIGS. 5 to 7 are flowcharts showing the operation of the microcomputer in the strobe device shown in FIG. 1;
FIG. 8 is a diagram showing a serial communication format between the camera body and the strobe device in one embodiment of the present invention, FIG. 9 is a diagram showing the same serial communication timing, and FIG. 10 is also a combination of the camera body and the strobe device. Figure, No.
FIG. 11 is a diagram showing the exchange of serial communication in cases I to IV of FIG. 10, and FIG. 12 is a diagram showing a display example on the display unit shown in FIG. 1 when dimming correction is possible and when it is not. 1 strobe device, 2 microcomputer, 3 display unit,
4 ... setting part, 11 ... camera body, 12 ... microcomputer, 13
…… Photometric circuit, 16… Comparison circuit.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G03B 15/05 G03B 7/00-7/28

Claims (2)

(57) [Claims] A determining means for determining whether or not a strobe device mounted is a strobe device capable of setting a correction value indicating a variable amount of a strobe light control level; and a strobe light control device according to a transmitted correction value. When the variable means for changing the level and the discriminating means determine that the electronic flash device is capable of setting a correction value, the correction value information set in the flash device is transmitted to the variable means, and the discriminating means is provided. If it is determined that the flash device is a strobe device for which a correction value cannot be set, a TTL control device having a dimming operation control means for transmitting correction value information indicating that the correction value is "0" to the variable means. Light capable camera. 2. A correction value setting means for setting a correction value representing a variable amount of a strobe light control level; an output means for outputting correction value information set by the correction value setting means; Determining means for determining whether or not the camera is capable of changing the light level, and prohibiting setting of the correction value if the determining means determines that the camera is not capable of changing the dimming level. And a flash device.