| 摘要 |
PURPOSE:To hold the quantity of exposure constant regardless of the brightness of an object by performing photography under shutter time control type exposure control when the required quantity of illumination light controlled according to the brightness of the subject is more than the maximum quantity of light of a lighting system. CONSTITUTION:When the brightness of the object 10 photodetected by a photodetection part 6 is smaller than brightness set in a comparator 12 as a reference level, photographic is carried out while lighting lamps 7 and 8 are dimmed below constant brightness held so far. On the other hand, when the level of an output electric signal inputted to the photodetection part 6 is higher than the reference level of the comparator 12, the comparator 12 outputs ''1'' and the driver 13 of a relay 15 outputs ''0'' to operate the relay 15. When a shutter switch is released in this state, a lighting dimming circuit 19 operates regardless of the output of the photodetection part 6 through a relay contact 17 and dims the lighting lamps 7 and 8 to some constant quantity of light which is determined previously in the dimming circuit. |
