A clapperboard is a device used in film, television, and advertising production to assist with the process of synchronizing the sound and film recordings. Because sound and film are usually recorded separately, they must be matched carefully during the editing process, or the resulting production will feel slightly off to viewers. When the synchronization is extremely poor, it may become almost comic, but even small discrepancies can be very disorienting for viewers.
are two components to a clapperboard: the clapper, and a slate. The
clapper consists of two pieces of wood or plastic which can be snapped
together to make a distinctive clacking noise which is easy to find on
the sound recording. By matching the sound of the clack to the physical
action on the film, the editor can synchronize the sound and film
recordings. Clapperboards are sometimes also given away as mementos of
The slate is used to record information about
the production, including the name of the production, the director, the
director of photography, and the scene. The take number and camera angle
are also written out on the slate. This information assists people in
the editing room, allowing them to quickly know what they are looking at
by reading the clapperboard.