JPH0714976Y2 - camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a camera, and more particularly to a camera having a device for displaying a warning when an inappropriate photographing condition is set.

For example, in a camera with an aperture priority exposure control method, information on subject brightness and film sensitivity is input, an aperture value is set by an external operation, and an appropriate shutter speed is calculated according to the input information and the set value. There is something. If the calculated shutter speed exceeds a predetermined range, for example, a range between the upper limit and the lower limit of the controllable shutter speed or the shutter speed below the shutter speed at which camera shake may occur, it is inappropriate. Conventionally, there is a display device that warns that the shooting conditions have been set.

However, even when such an inappropriate photographing condition is set, if the external operation is further performed to change the aperture value setting, the appropriate shutter speed calculated accordingly falls within the predetermined range. There are times. Even in such a case, the conventional display device merely gives a warning. Therefore, giving the impression that shooting is impossible, and
There were various problems such as not knowing which direction the external operation should be performed.

Therefore, in order to solve these problems, the applicant has devised a device that displays what kind of operation should be performed when inappropriate shooting conditions are set.

The above-mentioned device devised by the applicant will be described below with reference to the accompanying drawings.

FIG. 1 is a device devised by the applicant as described above, in which the power supply voltage is applied between the power supply lines Vcc and GND. The constant current source 1 gives a current to the variable resistors 2 and 3. The variable resistor 2 constitutes a film sensitivity input means and has a high resistance value when a high film sensitivity is set and a low resistance value when a low film sensitivity is set. The variable resistor 3 constitutes aperture value setting means, and the resistance decreases when the aperture is closed and increases when the aperture is opened. The light receiving element (photodiode) 4 receives an object. A photo diode 4 is connected between both input terminals of the operational amplifier 5, and a logarithmic compression diode 6 is connected to a feedback loop of the operational amplifier 5. Variable resistance 2,3
Output voltage biases the non-inverting input terminal of the operational amplifier 5. When the film sensitivity (SV), aperture value (AV), subject brightness (BV), and shutter speed (TV) are displayed in the Apex display, the output corresponding to TV = BV + SV-AV appears at the output terminal of the operational amplifier 5. . That is, the operational amplifier 5 generates the voltage V _T corresponding to the proper shutter speed. This voltage V _T is transmitted to the shutter controller via terminal 7. The aperture value of the lens can be arbitrarily selected by operating the preset aperture ring between the aperture value (maximum aperture diameter) and the maximum aperture value (minimum aperture diameter) peculiar to the lens. To do. Also, the voltage V _T is given to the voltage follower 8,
The voltage follower 8 operates the meter 9 to display the shutter speed. Further, the comparators 10 and 11 constitute a judging means for judging whether or not the proper shutter speed is within a predetermined range. Voltages corresponding to the proper shutter speed of the operational amplifier 5 are given to the inverting and non-inverting inputs of the comparators 10 and 11, respectively. Further, the non-inverting input of the comparator 10 is supplied with a high reference voltage Vref ₁ , corresponding to the maximum controllable shutter speed. A low reference voltage Vref ₂ according to the shake limit shutter speed is applied to the inverting input of the comparator 11. Therefore, when the proper shutter speed is between the controllable maximum shutter speed and the shake limit shutter speed, the voltage V _T corresponding to the proper shutter speed is
Is between both reference voltages Vref ₁ and Vref ₂ , and at this time the comparator
The output of 10,11 becomes H. Next, when the proper shutter speed is equal to or higher than the controllable maximum shutter speed, the voltage V _T becomes higher than the voltages Vref ₁ and Vref _2, and therefore the comparator 10 outputs L
It produces an output and the comparator 11 produces an H output. Further, when the proper shutter speed is lower than the shake limit shutter speed, the voltage V _T becomes lower than the voltages Vref ₁ and Vref ₂ , so the comparator 10 generates an H output and the comparator 11 generates an L output. To do. The LEDs 14 and 15 form display means. The resistors 16 and 17 are current limiting resistors. When the proper shutter speed exceeds the controllable maximum shutter speed, the output of the comparator 10 becomes L, so that a current flows through the LED 14 to turn it on. Further, when the proper shutter speed becomes lower than the shake limit shutter speed, the comparator 11 generates an L output, and a current flows through the LED 15 to turn it on.

Next, the operation will be described.

First, when the proper shutter speed calculated by the operational amplifier 5 is within a predetermined range, that is, below the controllable maximum shutter speed and above the camera shake limit shutter speed, the output voltage V _T of the operational amplifier 5 is the reference voltage. Since it is Vref ₁ or less and the reference voltage Vref ₂ or more, both comparators 10 and 11 generate an H output. Therefore, the LEDs 14 and 15 remain off. On the other hand, the voltage V _T is also given to the voltage follower 8, and the voltage follower drives the meter 9 to display the shutter speed. FIG. 2 shows the display in the finder. Inside the finder 18, there is a shutter speed instruction film 20, in which the shutter speed is indicated by the pointer 9a of the meter 9. The LEDs 14 and 15 are also displayed, but in this case both are off. This indicates that the shooting conditions are appropriate.

Next, when the proper shutter speed is higher than the maximum controllable shutter speed, the voltage V _T output by the operational amplifier 5 according to the proper shutter speed becomes higher than the reference voltages Vref ₁ and Vref ₂ . Therefore, the comparators 10 and 11 are L output and H output, respectively, and the LED 14 is turned on and the LED 15 is turned off. In this case, referring to FIG. 2, the LED 14 in the shape of the arrow on the right side lights up. This indicates a clockwise rotation of the diaphragm ring, that is, an operation of narrowing. Here, when the operation of narrowing down is performed according to the instruction, the resistance value of the variable resistor 3 decreases in association with the operation. Therefore, the output voltage V _T of the operational amplifier 5 becomes low.
That is, if the proper shutter speed is below the maximum controllable speed,
Further, when the shutter speed exceeds the shake limit shutter speed, the LEDs 14 and 15 are turned off in the same manner as the above operation, and it is understood that the photographing conditions are proper.

Next, when the proper shutter speed is equal to or lower than the shake limit shutter speed, the voltage V _T output by the operational amplifier 5 according to the proper shutter speed becomes lower than the reference voltages Vref ₁ and Vref ₂ . Therefore, since the comparator 10 generates the H output and the comparator 11 generates the L output, the LED 14 is turned off and the LED 15 is turned on. In this case, the arrow-shaped LED 15 shown in the second illustration is turned on to instruct the diaphragm ring to rotate counterclockwise, that is, open the diaphragm. When the opening operation is performed, the resistance value of the variable resistor 3 increases, and accordingly, the output voltage V _T of the operational amplifier 5 also increases. That is, the proper shutter speed is on the high speed side. When the appropriate shutter speed is below the maximum controllable shutter speed and below the camera shake limit shutter speed, LE
D14,15 goes out, and you can see that the shooting conditions have become appropriate.

In this example, both LEDs are turned off when there is a time output calculated between the maximum speed and the shake limit time, but it is also possible to turn on both LEDs.

This device is capable of operating the aperture ring and displaying the operating direction when the proper shutter speed exceeds the limit value.

However, when the proper shutter speed exceeds the maximum shutter speed and the aperture ring is set to the minimum aperture, the above-described device sets the proper shutter speed to the minimum shutter speed even if the aperture ring is operated. Cannot transition between fast shutter speeds. Also, when the proper shutter speed exceeds the minimum shutter speed and the aperture ring is set to the open aperture, the proper shutter speed is set to the maximum shutter speed and the minimum shutter speed even if the aperture ring is operated. You can't move between.

Therefore, even if the aperture ring is operated, shooting cannot be performed at an appropriate shutter speed, and the operation of the aperture ring becomes useless. In other words, there is a drawback that the operation is confusing when the proper shutter speed exceeds the limit value.

It is an object of the present invention to solve such a drawback and to provide a display device for a camera that does not bother the operation when the appropriate shutter speed exceeds a limit value.

FIG. 3 shows a first embodiment of the present invention. In this example, O
The configuration other than the R gate 21, switch 22, OR gate 23, and switch 24 is the same as that shown in the first diagram. The parts having the same functions as those shown in FIG. 1 are designated by the same reference numerals. In this embodiment, an OR gate 21 having an inverting input is provided on one side,
A switch 22 for opening and closing is connected between the inverting input and the negative power supply line GND, and the output of the comparator 10 is given to the other input. The output of the OR gate 21 is connected to the LED 14. The switch 22 is turned on to the maximum aperture value when the aperture value set by the external operation corresponds to the minimum aperture diameter that cannot be further reduced. Therefore, in that case, the shutter speed is higher than the maximum controllable shutter speed, and the comparator 10
Even if generates L output, the output of the OR gate 21 becomes H and the LED 14 remains off because the switch 22 is ON.
No more instructing to narrow down. Further, an OR gate 23 having an inverting input is provided on one side, a switch 24 for opening and closing the inverting input and the negative power supply line GND is connected, and the output of the comparator 11 is given to the other input. The switch 24 is turned on when the aperture value set by an external operation reaches an open aperture value that cannot be further opened. Therefore, when the open aperture value is set, even if the proper shutter speed becomes equal to or lower than the shake limit shutter speed and the output of the comparator 11 becomes L, the output of the OR gate 23 is output because the switch 24 is turned ON. Becomes H and LED15 goes out. That is, there is no need to give an instruction to open the diaphragm.

As described above, according to the present embodiment, if further narrowing or opening operations are impossible, instructions for those operations are not issued.

FIG. 4 shows a second embodiment of the present invention. The parts having the same functions as those shown in FIG. 1 are designated by the same reference numerals. The switch 22 is turned on when the maximum aperture value that cannot be further reduced is set, and the comparator 10 does not operate. Therefore, in this case, even if the proper shutter speed is equal to or higher than the controllable maximum shutter speed, the LED 14 does not light up, and the narrowing down is not instructed. Next, the switch 24 is turned on when the aperture value that cannot be further opened is set, and the comparator 11 is made inoperative. Therefore, in this case, even if the proper shutter speed falls below the shake limit shutter speed.
The LED15 will not light up and the narrowing down will not be instructed.

FIG. 5 shows a third embodiment of the present invention. The OR gate 21, the switch 22, the OR gate 23, the switch 24, the LEDs 14a and 15a, and the current limiting resistors 16a and 17a are different from those of the first embodiment, but other configurations are the same as those of the first embodiment. Similar to the example. The parts having the same functions as those shown in the first illustration are designated by the same reference numerals. The switch 22 is turned on when the maximum aperture that cannot be further reduced is set. Therefore,
At this time, when the proper shutter speed exceeds the controllable maximum shutter speed, the comparator 10 generates an L output, so that not only the LED 14 but also the LED 14a is turned on. FIG. 6 shows the display in the finder. When the LEDs 14 and 14a are turned on, not only is it necessary to indicate the necessary narrowing operation direction, but it is also possible that this is not possible. Therefore, in this case,
It is necessary to change the shooting conditions other than the aperture. Further, the switch 24 is turned on when the maximum aperture value that cannot be further opened is set. Therefore, at this time, if the proper shutter speed falls below the shake limit shutter speed, the comparator
Since 11 generates L output, not only LED15 lights up, but LED15a also lights up. It can be seen here that the operation to open the diaphragm is necessary and that it is impossible. Therefore, in this case, it is necessary to change shooting conditions other than the aperture, for example, to use auxiliary light of a speedlight.

FIG. 7 shows a fourth embodiment of the present invention. In this example, OR
Gate 21, oscillator 25, switch 22, OR gate 23, oscillator 26,
And a switch 24. The other configurations are the same as those in the first illustration, and the parts having the same functions are designated by the same reference numerals. Switch 22 turns on when the maximum aperture value (minimum aperture size) that cannot be further reduced is set,
It is turned off at other times. Switch 22 of oscillator 25 is ON
It operates at the same time and gives an oscillation output to the OR gate 21.
The switch 24 is turned on when an open aperture value (maximum aperture diameter) that cannot be further opened is set, and is turned off at other times. The oscillator 26 is a switch 2
When 4 is turned on, it operates to give an oscillation output to the OR gate 23.

Next, the operation will be described.

First, when the proper shutter speed is below the controllable maximum shutter speed and above the camera shake limit shutter speed, the same operation as the circuit shown in FIG. 1 is performed and the LEDs 14 and 15 remain off. This is a display indicating that the shooting conditions are appropriate.

When the proper shutter speed is equal to or higher than the controllable shutter speed and the set aperture value is between the maximum aperture value and the maximum aperture value, the switch 22 is OFF and the oscillator 25 does not operate.
The output is given to the OR gate 21. On the other hand, at this time, since the output of the comparator 10 is L, the output of the OR gate 21 is constantly L.
This indicates that the LED 14 should be constantly lit and that the narrow-down operation should be performed.

When the proper shutter speed is equal to or higher than the maximum controllable shutter speed, and the set aperture value is the maximum aperture value (minimum aperture size), the switch 22 is ON and the oscillator 25 operates and the oscillation output is OR gated. Give to 21. Further, since the oscillator 10 is producing the L output, the OR gate OR gate 21 produces the output of the oscillation frequency of the oscillator 25, causing the LED 14 to blink. this is,
Display that narrowing-down operation is necessary but impossible.

When the proper shutter speed is slower than the shake limit shutter speed and the set aperture value is not opened to the maximum opening, the switch 24 is OFF, the oscillator 26 is inactive, and the OR gate 23 is provided with an L output. Further, since the output of the comparator 11 is L, the OR gate 23 constantly generates the L output. Therefore, the LED 15 lights up constantly to indicate that the operation of opening the diaphragm is necessary and possible.

Next, when the proper shutter speed is equal to or lower than the shake limit shutter speed and the set aperture value is the open aperture value (maximum aperture diameter), the switch 24 is turned on and the oscillator 26 operates to output the oscillation output to the OR gate 23. give. On the other hand, the comparator 11 gives the L output to the OR gate 23. Therefore, the OR gate 23
Generates an output of the same frequency as and causes LED15 to blink. This indicates that an operation to open the iris is necessary but not possible. This leads to recommendations for strobe usage.

Although the lower limit of the shutter speed is set to the shake limit shutter speed in the above embodiment, the lower limit may be set to the lowest controllable shutter speed.
It is within an arbitrarily selectable range.

As described above, according to the present invention, when the set shooting conditions (shutter speed and aperture value) are not appropriate (when the exposure amount is not appropriate), and the photographer operates the aperture value setting means. If it is possible to set the proper shooting conditions by doing so, the display state of the display for instructing the external operation of the aperture value setting means is switched (when the photographer operates the aperture value setting means, Depending on whether there is a possibility of setting shooting conditions or not at all,
Since the display state of the display is switched), the photographer is not confused.

[Brief description of drawings]

FIG. 1 is a view showing an apparatus devised by the applicant, FIG. 2 is a view showing a display in a finder when the apparatus shown in FIG. 1 is used, and FIG. 3 is a first embodiment of the present invention. FIG. 4 is a view showing a second embodiment of the present invention, and FIG.
FIG. 6 shows a third embodiment of the present invention, and FIG. 6 shows a fifth embodiment.
FIG. 7 is a view showing an in-viewfinder display device using the illustrated device, and FIG. 7 is a view showing a fourth embodiment of the present invention. [Explanation of Signs of Main Parts] Photoelectric conversion means …… 4 Film sensitivity information input means …… 2 Aperture value setting means …… 3 Computing means …… 5 Judging means …… 10,11 Display means …… 14,15

Claims (6)

[Scope of utility model registration request] 1. A photoelectric conversion means for generating an output corresponding to the brightness of an object, an aperture value setting means that is externally operable and sets an aperture value according to the operation, an output of the photoelectric conversion means and the aperture. In a camera having a calculating means for calculating a proper shutter speed based on the aperture value set by the value setting means, and controlling the shutter speed by the output of the calculating means, the proper shutter speed is set to a high speed side or a low speed side. First determining means for determining that the limit value is exceeded, and second determining means for determining that the aperture value set by the aperture value setting means has not reached the limit value on the aperture side or the open side. , The appropriate shutter speed exceeds the limit value on the high speed side based on the outputs of the first and second determination means, and the set aperture value has not reached the limit value on the aperture side. And,
Alternatively, when it is determined that the appropriate shutter speed exceeds the lower limit value on the low speed side and the set aperture value does not reach the limit value on the opening side, a determination unit that generates an instruction signal, and the aperture value A camera comprising: a display unit that displays an instruction to instruct an operation on a setting unit; and a display control unit that operates the display unit according to the instruction signal. 2. A camera according to claim 1, wherein the limit value on the high speed side is a controllable highest shutter speed. 3. The camera according to claim 1 for utility model registration, wherein the low-speed limit value is a controllable lowest shutter speed. 4. The camera according to claim 1 for utility model registration, wherein the low-speed limit value is a handshake limit shutter speed. 5. The camera according to claim 1 of the utility model registration claim, wherein the control means has a proper shutter speed exceeding a limit value on the high speed side, and a set aperture value on the aperture side. A camera characterized in that when the value has not reached the value, a display for instructing to operate the aperture value setting means to the aperture side is displayed on the display means. 6. The camera according to claim 1 of the utility model registration, wherein the control means has a proper shutter speed exceeding a limit value on the low speed side and a set aperture value on the open side. A camera characterized by causing the display means to perform a display instructing to operate the aperture value setting means to an open side when the value has not reached.