Shutter time control circuit

A shutter control circuit for a shutter having a mechanical condition producing a delay, comprising:

• (a) a counter circuit for counting pulses when a shutter release operation is performed;
• (b) preset means having impedance means for adjustably presetting time information corresponding to a mechanical condition of the shutter mechanism;
• (c) detecting means for producing a detecting signal when the value counted by said counter circuit has assumed a value corresponding to said impedance means;
• (d) a shutter time information setting circuit including a first part for setting a digital value corresponding to the exposure time and a second part to which the output of said counter circuit is connected, said second part being responsive to the output of said detecting means arranged for setting a digital value corresponding to the content of the counter when said detecting means produces an output;
• (e) a shutter time control circuit coupled to said counter circuit and the first and second parts of said shutter time information setting circuit for forming a shutter closing signal when the value counted by said counter circuit has assumed a value corresponding to the sum of the digital values set by said first and second parts of the shutter time information setting circuit;
• and
• (f) means for closing the shutter in response to the closing signal.

A shutter control circuit for a shutter having a mechanical condition producing a delay, comprising:

• (a) a counter circuit for counting pulses when a shutter release operation is performed;
• (b) preset means having impedance means for adjustably presetting time information corresponding to a mechanical condition of the shutter mechanism;
• (c) a timer for counting the time and producing an output after counting the time corresponding to the impedance of said impedance means, said timer being arranged to be actuated by the shutter release operation;
• (d) a shutter time information setting circuit including a first part for setting a digital value corresponding to the exposure time and a second part to which the output of said counter circuit is connected, said second part being responsive to the output of said timer and arranged for setting a digital value corresponding to the content of the counter when said timer produces an output;
• (e) a shutter time control circuit coupled to said counter circuit and the first and second parts of said shutter time information setting circuit for forming a shutter closing signal when the value counted by said counter circuit has assumed a value correspoding to the sum of the digital values set by said first and second parts of the shutter time information setting circuit;
• and
• (f) means for closing the shutter in response to the closing signal.

A shutter control circuit for a shutter having a mechanical condition producing a delay, comprising:

• (a) a counter circuit for counting pulses when a shutter release operation is performed;
• (b) preset means having impedance means for adjustably presetting time information corresponding to a mechanical condition of the shutter mechanism;
• (c) a shutter time information setting circuit including a first part for setting a digital value corresponding to the exposure time and a second part, said second part having converting means for converting the time information preset by said impedance means into a digital value and setting the digital value converted by said converting means;
• (d) a shutter time control circuit coupled to said counter circuit and the first and second parts of said shutter time information setting circuit for forming a shutter closing signal when the value counted by said counter circuit has assumed a value corresponding to the sum of digital values set by said first and second parts of the shutter time information setting circuit;
• and
• (e) means for closing the shutter in response to the closing signal.