| 摘要 |
PURPOSE:To execute photographing of a special intention, by constituting so that photographing is executed by a desired exposure time when the desired exposure time is longer than a prescribed value, and an exposure time which is capable of synchronous flash is provided, when said exposure time is short. CONSTITUTION:While an input terminal J11 is high, a transistor TR11 conducts, an electromagnet 10 is energized, and also, to a non-inverted input terminal of a comparator 16, voltage of a constant-voltage circuit 17 is inputted as it is. Therefore, when an exposure time set by a variable resistance 3 is shorter than a flash synchronizing limit speed, TR9 becomes non-conducting earlier than TR11, therefore, the exposure time is controlled by TR11, and immediately after a flash discharge tube 4b has emitted light by synchronizing with full opening of the shutter, closing of the shutter is started. In this case, a displaying circuit 21 displays the exposure time of the flash synchronizing limit speed. When the exposure time set to a manual operation is longer than the flash synchronizing limit speed, TR9 conducts when TR11 has become non-conducting due to light emission of a discharge tube 46, it becomes non-conducting after the set exposure time has passed, and closing of the shutter is started. |
