This circuit gives multiple `stop-action` photographic effects like showing a bouncing ball in up to nine locations in a single photograph. The circuit will automatically fire the bulbs sequentially with the time between each firing variable. The circuit is functionally complete except for the actual firing system. In many cases, a simple SCR will work, as shown. The firing can be initiated in one of two ways
A trigger pulse can be applied to the trigger input terminal through a capacitor, or can operate the unit as a slave. Light from a. camera-mounted flash will activate the circuit through its built-in photocell pickup. The time period between each successive flash is determined by Cl and Rl, which is variable. After firing the circuit, it must be reset by momentarily depressing the reset button.