| 摘要 |
A camera shutter includes sectors 16 and 17 pivotably mounted for movement to and fro to open and close a shutter opening. Movement of the sector 17 is detected by a photocoupler 19 whose beam 19a is interrupted or allowed to pass by a part which passes across the beam. The time of initial interruption represented by TS is used to calculate the initial speed of the sector 17 and this is used to determine the time of continued opening of the sector. A matrix of such timings is contained in a read only memory 30a in a central processing unit 30, which timings are accessible by brightness dependent exposure quantities and the measured initial speed values. In addition a data modification circuit 28 contains selectively operable switches S by operation of which binary values may be addressed to the CPU 30 to modify the measured initial speed values used to address the matrix for obtaining timings. As the timings set in the read only memory in production refer only to average camera values, and errors may be detected upon trials of a camera, the switches S are selectively operated to overcome the errors in practice. <IMAGE> |
