| 摘要 |
PURPOSE:To obtain automatically the proper quantity of exposure even in daylight synchronization by selecting a minimum values which is common between two aperture values based upon distance information from a distance detecting circuit and stationary light measurement. CONSTITUTION:For example, a shutter is released and light is emitted by a discharge tube 1 through the operation of a preliminary light emitting circuit with a pulse from a pulse generator 16; and reflected light from a subject strikes on a photodetecting element and a voltage corresponding to its quantity of photodetection inverts outputs of some of comparators, e.g. 37-39. Then, when comparators 43 and 44 corresponding to the ambient brightness of a stationary light measuring circuit 64 are in an inverted state, a selector 55 decides a common minimum aperture F5.6 and a main discharge tube 2 emits light corresponding to F5.6 with a pulse from a delay circuit 17. Comparator groups 37-42 and 43-48 correspond to aperture values. Therefore, an aperture value is determined on the basis of aperture information based upon the ambient brightness and distance information to control the quantity of emitted light, and the quantity of light is controlled automatically even in daylight synchronization to obtain the proper quantity of exposure.
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