摘要 |
In a photographic flash device comprising a main capacitor (1) for storing a large electric energy, a gas-discharge flash tube (4) to be lit by the electric energy of the main capacitor (1), a switching circuit (5+9) which switches off the discharging of the flash lamp (1), a control circuit (20) which controls the switching circuit (5+9) in a manner to switch the switching circuit (5+9) off at a sending of a stopping signal from a triggering circuit (20) to the switching circuit (5+9), and a timer circuit which controls, responding to a selected guide number (G.N.) of flash photographing, the time period from the start of flashing of the flash tube (4) to a sending of a stopping signal to the control circuit (20) (namely the time period of flashing), the improvement is that the time period is adjusted responding to the voltage across the main capacitor (1).
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