To efficiently cancel the prohibition setting of flash light emission.

An IC 18 incorporated in a stroboscopic device 14 is provided with a photographing frequency counter 33. When the frequency of contact of a synchro switch 20 reaches the photographable frequency, the action of a 1st boosting circuit 25 is prohibited to make it impossible for the stroboscopic device 14 to emit flash light and a validating circuit 32 is activated to start picking up a sound from a microphone 19. An audio signal inputted from the microphone 19 is compared with a previously stored reference audio information. When the audio signal and the audio information coincide, the function of the 1st boosting circuit 25 returns to allow emission of flash light.