*Traditional film setting:* both camera and tape recorder equipped with a special crystal sync control unit that governs the speed of both units. To make editing simple, a slate with a clapper is filmed with the sound of the clapper closing recorded. In editing, the two are matched.

*Time code slates:* Slate and recorder time codes are matched. The frame on which the sticks have closed and banged is noted as the sync point for the picture and sound.