JPS63253337A - Film sensitivity setting device - Google Patents

Abstract

PURPOSE:To freely change information on film sensitivity by providing a modifying means which modifies film sensitivity by prescribed steps in accordance with manual operations. CONSTITUTION:The titled device includes the means which sets film sensitivity information to a camera according to sensitivity information read out of a film and which increases and decreases the set film sensitivity by a few steps, i.e. 1/3 Sv, and a resetting means which resets the film sensitivity that has been modified by the increasing and decreasing means to its original, i.e. the sensitivity that is read out of the film. Namely, a film sensitivity manually setting means 3 is operated by a set sensitivity increasing means UP, a set sensitivity decreasing means DW and a resetting means RE. Thus more sensitive photographing and the exposure correction photographing whose exposure is shifted from an appropriate exposure is attainable.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a film sensitivity setting device for a camera.

RESEARCHDISCLO8UR is a technology that writes a code representing the film's sensitivity at the beginning of the film and installs a device inside the camera that reads this code to automatically set the film sensitivity in the camera.
E Aprie1980 142 pages 19223 P
Photographic fii! m codin
It is published in g. In the method described in this document, the film sensitivity is written in binary code at the beginning of the film, and a code hole is punched between the film advance perforations to detect the film advance perforation date. A detector for detecting the hole as the code and a detector for detecting the hole as the code are arranged side by side, and the binary code is read by the cooperation of the two.

When using the method described above, the camera user does not have to manually set the film sensitivity on the camera each time the film is loaded, and the film sensitivity is automatically set, which prevents forgetting or making mistakes in setting the sensitivity. Although this is very convenient, it has the inconvenience of not being able to freely set the film sensitivity value to be set in the camera when performing sensitized photography. For example, sensitized photography uses I5O400 film,
This is a photographing technique in which exposure conditions are set as 3200, a photograph is taken, and then sensitization and development processing is performed.

In addition, consider the final image quality such as graininess, and the latitude of the film to lower the film sensitivity (
For example, even with a film of 15O200, the setting (rsOloo) may be used to take slightly overexposed photographs. In such a case, the film sensitivity value set in the camera is different from the sensitivity value of the loaded film, but the technology published in the above-mentioned document uses the film sensitivity information set in the camera when frequently performing such shooting. Cannot be changed arbitrarily.

The present invention is based on the technology disclosed in the above-mentioned literature, and has been made with the object of solving the inconvenience caused when photographing is frequently performed by changing the set film sensitivity.

Therefore, in the present invention, film sensitivity information is set in the camera based on the sensitivity information read from the film, and the set film sensitivity is increased/decreased by -steps in the film sensitivity, for example, by 1/SSv, and this increase/decrease means is used to change the film sensitivity. A reset means is provided for returning the film sensitivity to the original film sensitivity, that is, the sensitivity read from the film. The present invention will be explained in detail below with reference to Examples.

FIG. 1 shows one embodiment of the present invention, and in order to facilitate understanding of the concept of the invention, each functional part is represented by a block, and the specific configuration of these blocks is shown in FIGS. 2 to 4. Indicated. The illustrated device is installed in a camera and used for sensitized photography, and in FIG. 1, 1 reads the code of the film sensitivity value recorded at the beginning of the film loaded in the camera. , a sensitivity value code reading means for outputting film sensitivity data, the specific construction of which is shown in FIG. Reference numeral 3 denotes a manual film sensitivity value setting means, which is operated by a setting sensitivity increasing means UP, a setting sensitivity decreasing means DW, and a reset means RE, which are operated by manual members. Reference numeral 5 denotes an adder circuit that reads the original sensitivity value of the loaded film, which is the output of the sensitivity value code reading means 1, and the sensitivity value (sensitization value) set by the manual film sensitivity value setting means.
and outputs a signal with the assumed sensitivity value.

In this embodiment, the manual film sensitivity value setting means 3 is not the same as the sensitivity value (sensitization value) planned for shooting (but also data indicating how much the sensitivity should be changed from the current film sensitivity in order to achieve this sensitivity). Therefore, the output signals of the two blocks 1 and 3 are added by the adding circuit 5.The exposure control device 15 of the camera adds the output signals of the two blocks 1 and 3 in accordance with the film sensitivity value which is the output of this adding circuit. Exposure control operation is performed. Reference numeral 7 denotes a display device that indicates that the camera is set to manual film sensitivity setting shooting mode.

Both the output signal of the film sensitivity reading means 1 and the output signal of the manual film sensitivity value setting means 3 are multi-bit signals in which numerical values related to film sensitivity are encoded in binary. Each bit of the output of the manual film sensitivity value setting means 3 is 0, that is, a low level, and when performing sensitized photography, the output line O! of block 3 is output. Since at least one of ~Oa becomes high level, this high level signal is sent to the display device 7 through the OR circuit ORI, and the display device 7 displays that the camera is set to the manual film sensitivity setting shooting mode. do.

The storage device 13 is a magnetic storage device such as a RAM or a magnetic storage device equipped with a writing and reading device, or an electrochromy device, which is constantly supplied with power from the time the film is loaded until all the frames have been photographed or the film is taken out midway. Consists of non-volatile memory.

The setting sensitivity display device 17 displays the normal sensitivity of the film used when shooting is not performed using manual film sensitivity setting, and displays the set film sensitivity when shooting using manual film sensitivity setting, but this display is not always performed. Since there is no need to display the camera, it is better to have a configuration that displays the display only when the photographer presses the display button.

FIG. 2 shows a specific circuit configuration of the film sensitivity reading means 1 shown in FIG. In FIG. 2, F is a film and PH is a perforation for feeding the film. The film sensitivity code is 6-bit data, with the part between two perforations at the beginning of fill 11 as 1 bit, and these 6 bits and 1-bit codes each indicating the beginning and end of the sensitivity data code. Area S for 8 bits in total
Recorded in H. The code is recorded as number 1 if there is a hole between the perforations in the region SH, and as 0 if there is not. This code is read using two sets of light emitting diodes Ll, L2 and light receiving elements PD1. P
It consists of D2. These light emitting diodes and the light receiving element face each other with the film F in between, and the perforation PH of the film F and the through hole 11 as a code pass through the pair of the light emitting diode L1 and the light receiving element PDI. It has become. Only the perforations of the film F pass between the pair of light emitting diode L2 and light receiving element PD2.

Therefore, the output of the photodetector PDI is perforation PH
It includes both the detection signal of the code hole and the detection signal of the code hole.

Further, the output of the light receiving element PD2 includes only the detection signal of the perforation PH of the film F. So PDI
By subtracting the output signal of PD2 from the output signal of , only the code hole detection signal is obtained. This subtraction operation is performed by the light receiving element P.
An AND gate ANO is opened and closed using a signal obtained by inverting the output of D2 by an inverter INO, and the output of the light receiving element PDI is taken out through this AND gate ANO. What is indicated by b in the time chart of FIG. 3 is the code hole detection signal train obtained in this way, and FIG. 3a is the perforation detection signal train which is the output of the light receiving element PD2. Second
Returning to the figure, ST is a hole indicating the beginning of recording the sensitivity code, SE is a hole indicating the end of recording the sensitivity code, and the sensitivity code is recorded between ST and SE. During the process of loading film into a camera and winding the film until the first frame is at the photographing position, the film moves in the direction of the rightward arrow in FIG. 2, and during this time the sensitivity code described above is read. As mentioned above, the code hole detection signal is a pulse train as shown in FIG. 3, and is a temporally series signal. The circuit shown in Fig. 2 converts this time series signal into a time parallel signal and stores it in the storage device 13 (Fig. 1). The signal train shown in the figure is read into the shift register while being shifted by the perforation detection signal shown in FIG. 2, and the train of JK flip-flops JPI to JF6 in FIG. 2 constitutes the shift register.

The circuit configuration and operation of FIG. 2 will be described in further detail below with reference to the time chart of FIG. 3. Figure 3 shows the case where the film sensitivity value is recorded as 110110 in 6 binary bits, and the first pulse signal (left end) in the figure shows the detection of the through hole ST indicating the start of recording in Figure 2. The last (rightmost) pulse in the signal is a detection signal of the through hole SE indicating the end of recording. When the film is loaded into the camera and the back cover of the camera is closed, power is supplied to a winding mechanism (not shown) and the circuits shown in FIGS. 1 and 2, and the film is wound up to the first frame. 21 is a circuit that lights up the light emitting diodes L1 and L2, and 23 and 24 are light receiving elements PDI and PD2.
This is a circuit that shapes the output of

FFI is an RS-flip-flop and is reset at the rising edge of the output of the inverter INI, that is, the falling edge of the signal from terminal a (Fig. 3 a), and the signal from the output terminal A of the AND gate ANO shown in Fig. 3 is reset. Since it is set at the rising edge, the Q output C of this flip-flop FFI is the third
The waveform shown in Figure C is output. In addition, R8-flip-flop FF2 and hexadecimal counter CO1 are reset output from a power-on reset circuit (not shown) when the film (F) is attached, the back cover is closed, and power supply is started. It is reset by the signal FOR. Therefore,
The carry terminal CY of the counter CO1 and the Q output of the flip-flop FF2 are at "Low". However, the detection signal of the through hole ST is still the carry terminal output of the counter COI is 0, and the output of the inverter IN2 is “High”.
Therefore, the output from the AND circuit AN2 sets the flip-flop FF2, and the Q output d becomes "High".
AND circuit AN3 is opened, and the third
As shown in Figure e, a detection signal of the perforation PH is output by the light receiving element PD2.

JK - The circuit composed of flip-flops JF1 to JF6 constitutes a serial input/parallel output shift register, and these flip-flops JF1 to JF6
is reset by the above-mentioned power-on reset signal FOR, and the output e of the AND circuit AN3 is used as a clock pulse, and the rising signal of this clock pulse is used to sequentially output the Q output of the flip-flop FF1 in FIG. 3C. Transfer from P1 to P6. This situation is shown in Figure 3 PI-
It is shown in P6. In addition, the clock pulse from the output e of the AND circuit AN3 is also input to the clock terminal of the heptadary counter COI, and this counter receives the rising edge of the clock by 7
When the count is counted, the carry terminal output f becomes "High" (FIG. 3 f). Therefore, the gate of the AND circuit AN2 is closed and the AND circuit ANI is opened, so that the through hole SE
The signal from the output terminal of the AND circuit ANO (third
The pulse signal at the right end in the figure) is output from the AND circuit AN1, and the flip-flop FF2 is reset and its Q
The output terminal i becomes “Low” and the AND circuit AN3
is closed and the clock pulse shown in FIG. 3e is not output.
Outputs P1 to P6 of F2 no longer change, and terminals P6 to P
The output of 1 is the same as the sensitivity signal recorded on the film.
It is 6-bit film sensitivity data of 10110''.

FIG. 4 shows a specific configuration of the manual film sensitivity value setting means 3 shown in FIG. 1, which is suitable for sensitized photography. The sensitivity value (sensitivity increase) is set by operating the up and down buttons (not shown). By pressing the up or down button once, the sensitivity can be increased or decreased by -steps in film sensitivity, for example 1/S S v. CO2 is a 2-bit up-down counter, and CO3 is a 4-bit up-down counter to which the carry signal or borrow signal of counter CO2 is input, both forming a 6-bit up-down counter. Switch SW1 is a switch linked to the above-mentioned UP button, switch sW2 is a switch linked to the DOWN button, and SW3 is a switch linked to a reset button (not shown). These buttons and switches are UP in Fig. 1.
, DW, and RE. When the back cover of the camera is closed and power is supplied to the circuit, a reset signal FOR is applied to the reset terminals of counters CO2 and CO3 through OR circuit OR3, and both counters are reset.

In this state, the outputs 01 to 06 of each bit of the counters c02 and CO3 are all O (low level), so the NAND circuit N
The output of AN1 is 1 (high level), and the output of OR circuit OR4 is O. Therefore, the AND circuit AN4 is open upon receiving the high level signal from the NAND circuit NAN1 at one terminal, and the AND circuit AN5 is closed because the output of OR4 is low. When the up button is pressed, the switch SWI closes and the one-shot circuit O8I is triggered, and one pulse is outputted to the AND circuit AN4 and the embodiment counter CO2.
is applied as an up signal. When the down button is pressed, the switch SW2 closes and one pulse is output from the one-shot circuit O32 and applied as a down signal to the counter CO2 through the AND circuit AN5, but initially, as described above, the AND circuit AN4 is open and AN5 is closed. So,
Only the up button operation is valid. In other words, operation is possible only in the direction of sensitization. When the up button is pressed many times, the 6-bit counter consisting of counters CO2 and CO3 adds up the number of times the up button is pressed, and the output of output lines 01 to 06, whichever is less (one output is 1 (high level) Then, since the output of the OR circuit OR4 becomes high, the AND circuit AN5 is also opened, and the operation of the down button becomes valid, so that the counting output of the counters CO2 and CO3 can be arbitrarily decreased, that is, the sensitivity can be adjusted. It becomes possible. Output terminals 01 to 0 of counters CO2 and CO3
When all the outputs of 8 become 1, the output of NANI becomes low and the AND circuit AN4 is closed, and any further press of the up button becomes invalid, and only the operation of the down button is valid. With the above configuration, operate the up and down buttons to input 6-bit binary data to the counters CO2 and CO3.
This data can be outputted to the output terminal Of=Oa of , and this data is inputted to the addition circuit 5 in FIG. 1 as the output of the manual film sensitivity value setting means 3. If you want to cancel the settings, press the reset button (not shown) and switch SW3
is closed and the counters CO2 and C are passed through the OR circuit OR3.
A reset signal is applied to O3, and CO2°CO3 is reset.

The film sensitivity setting device of the present invention has the above-mentioned configuration,
In a camera that controls exposure based on the film sensitivity read from the film itself, it is possible to control exposure by changing the film sensitivity read above, so it is possible to use a technique called sensitized photography and to adjust the exposure value from appropriate exposure. It is now possible to shoot with shifted exposure compensation. Then, it is possible to easily return to the standard photographing state by the reset means.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a first embodiment of the present invention, FIG. 2 is a specific configuration example of the film sensitivity data reading device shown in FIG. 1, and FIG. 3 is for explaining the operation of FIG. 12. The time chart in FIG. 4 is a specific example of the structure of the film sensitivity data setting device shown in FIG.

Claims (1)

[Claims] A reading means for reading a digital signal corresponding to the sensitivity of film loaded in the camera; a digital signal read by the reading means;
a changing means for changing the film sensitivity by a predetermined step in response to a manual operation; and a digital signal read by the reading means from a changed value of the digital signal changed by the changing means in response to the manual operation. A film sensitivity setting device comprising: a reset means for returning the camera to a normal state; an exposure control means for controlling exposure of the camera based on the digital signal; and a display means for displaying based on the digital signal.