Flatbed editor

A flatbed editor is a type of machine used to edit film for a motion picture.

Picture and sound rolls are placed onto separate motorized disks, called "plates," and then threaded through picture and sound transports, each of which has sprocket rollers that transport the film or magnetic stock forwards or backwards at variable or fixed speeds while maintaining their precise positions. The transports can be "locked" together, either mechanically (KEM, Steenbeck, Showchron) or electronically (Moviola), so that they move in harmony and maintain synchronization between picture and sound. They can also be unlocked to move them independently. A prism reflects the film image onto a viewing screen, while a magnetic playback head reads the magnetic audio tracks. The two most common configurations are the "six-plate" (one picture transport and two sound transports) and the "eight-plate" (two picture and two sound transport) models. (The edges of two of the plates on the six-plate model can be seen pictured at the right.)