| 摘要 |
<p>PURPOSE:To cause no photographing error even in case of a camera having no camera shake alarm informing means, by executing photometry of luminance of an object to be phtotgraphed, informing the low luminance in case of a prescribed value or below, also supplying a DC power supply to a main capacitor of an electronic flash device. CONSTITUTION:When a switch (S) 9 is turned on, a base current flows to a transistor (TR) 10 from a DC power supply 1, the TR10 is turned on, electric power is supplied to a photometric circuit 13, luminance of an object to be photographed is photodetected by a photodetector 11, and it is detected by a luminance level detecting circuit 12. In a state that there is the possibility of causing a camera shake due to a low detecting level of luminance of the object to be photographed, the fact that light emission of a flash tube 7 is required is informed by an alarm informing circuit 8, by an output signal from the circuit 2 is also operated, the electric power supply 1 is supplid to a DC-DC converting circuit 3, and a main capacitor 4 is charged. When a trigger S5 is turned on after prescribed charging, a triggering circuit 6 is operated, the flash tube 7 emits light, and flash photographing is executed. In this wya, photographing error can be prevented.</p> |
