Flash control system for camera - makes use of shutter closing signal to generate flash discharge quenching pulse

摘要

The flash gun control for the camera uses the shutter closing signal, or the removal of current to the shutter electro magnets, to generate the quenching pulse for the flash discharge. It enables the integral exposure meter to monitor the reflected flash and control an accurate exposure. The light sensing element is a non inertial type e.g. a photo diode so that a responsive and accurate exposure is obtained. The system can be used for fast films for specialised applications. The film speed can be marked on the film carrier, with a monitor to sense the type of marking and correct the exposure.