Follow Focus
A geared mechanism that allows focus to be adjusted precisely and repeatably, usually by a second operator.
Measured in
degrees
In depth
A follow focus provides a marking disc on which positions can be recorded, so a rehearsed move can be repeated exactly take after take. Wireless versions let a focus puller work from beside the subject rather than at the camera, which is essential when the camera is on a gimbal or a crane.
Examples in practice
Two marks on the disc let a focus puller move between an actor's start and end positions identically on every take.