<p>The automatic flash system for a camera has a voltage amplifier (1) forming a booster for the power supply (E) connected by a diode (2) to the flash tube (5) and its quenching tube (6). Interconnected with them is a monostable multivibrator (14) for the booster, and a trigger circuit (4) preceding the flash tube. Between this part of the circuit and a parallel section containing two operational amplifiers (11, 12) and a trigger circuit (13) for providing signals corresponding to light reflected from the subject, is a delay device (7). This controls the input amplifier (11) after operation of the flash tube. The voltage amplifier is delayed for a given time by a signal which triggers the flash tube.</p>
