| 摘要 |
PURPOSE:To realize appropriate automatic exposure control, by correcting the difference between the multiple photometric output and output of photoelectric element for minitor. CONSTITUTION:Before release action of a camera, a processing circuit A2 to input photometric outputs P1-P5 by TTL open photometry from a photometric circuit A1 outputs an optimum multiple photometric output P6 of the conditions of a subject. In succession, an operating circuit A3 computes Pans1 from outputs P1, P6- P8, and applies the result to an operating circuit A5. After release action, the circuit A3 holds Pans1 under the control of sequence controlling circuit A9, and an aperture controlling circuit A6 operates to obtain a photometric output P1 of a photoelectric element for minotor PD1. The circuit A5 inputs the output P1 and the output of circuit A3, and computes, and applies an output Pans2 into the circuit A6. This output Pans2 expresses the shutter speed which is determined by the multiple photometric output P6 and aperture value Au. That is, the difference between the output P1 and output P6 is corrected at this point. Then, the circuit A6 operates a composite electromagnet Mg to block the stop-down. A shutter control circit A7 integrates the exposure time from the start of exposure by the running of the front curtain, and when the outpt of this circuit reaches the specified relation, the shutter rear curtain is closed. |
