Shutter timing apparatus

Claim 1

IN A PHOTOGRAPHIC CAMERA, AND EXPOSURE TIMING CIRCUIT INCLUDING PHOTORESPONSIVE MEANS HAVING AN ELECTRICAL PROPERTY WHICH VARIES IN MAGNITUDE IN ACCORDANCE WITH THE INTENSITY OF LIGHT INCIDENT ON SAID PHOTORESPONSIVE MEANS, SAID CIRCUIT COMPRISING FIRST ACTUATING MEANS SELECTIVE OPERABLE TO INITIATE A TIME INTERVAL; SECOND ACTUATING MEANS OPERABLE TO TERMINATE SAID TIME INTERVAL IN RESPONSE TO THE TIME INTEGRAL OF SAID ELECTRICAL PROPERTY, COMMENCING AT INITIATIONOF SAID TIME INTERVAL, REACHING A PREDETERMINED VALUE; SAID PHOTORESPONSIVE MEANS BEING CHARACTERIZED BY HAVING A TIME LAG BETWEEN A CHANGE IN THE INTENSITY OF LIGHT INCIDENT THEREON AND THE CORRSPONDING CHANGE IN THE VALUE OF SAID ELECGTRICAL PROPERTY BEARS DIFFERENT RELATIONSHIPS TO THE TIME INTEGRAL OF THE INTENSITY OF LIGHT INCIDENT OF SAID PHOTORESPONSIVE MEANS WHEN OF LIGHT INCIDENT ON SIAD PHOTORESPONSIVE MEANS WHEN SAID INTENSITY IS SUBSTANTIALLY CONSTANT AND WHEN SAID INTENSITY VARIES; AND COMPENSATING MEANS MOVABLE BETWEEN A FIRST POSITION WHEN THE INTENSITY OF LIGHT INCIDENT ON SAID PHOTORESPONSIVE MEANS IS SUBSTANTIALLY CONSTANT DURING SAID TIME INTERVAL, AND A SECOND POSITION, WHEN THE INTENSITY VARIES DURING SAID TIME INTERVAL, MOVEMENT OF SAID COMPENSATING MEANS FROM SAID FIRST TO SAID SECOND POSTION BEING EFFECTIVE TO ESTABLISH A RELATIONSHIP BETWEEN SAID TIME INTEGRAL OF SAID ELECTRICAL PROPERTY AND SAID TIME INTEGRAL OF LIGHT INTENSITY INCIDENT ON SAID PHOTORESPONSIVE MEANS WHICH IS SUBSTANTIALLY THE SAME WHEN SAID INTENSITY VARIES DURING SAID TIME INTERVAL AS WHEN SAID INTENSITY IS COSTANT DURING SIAD TIME INTERVAL.