baby: A small spotlight.
baby legs: A short adjustable tripod used for low-angle shots. Called a shorty in the USA.
back coating: A thin conductive coating applied to the non-magnetic side of recording tapes to improve winding qualities, particularly at high speed.
back focus: The distance from the rear element (3) of a lens to the image plane.
background: (1) The main video picture source in a keyer.(2) Sound that defines the nature of a location. Called atmosphere or atmos in the UK. (3) The visible area in a shot behind the main action of the scene. (4) In computer graphics or animation, the image layer furthest from the viewer.
background light: Light shining on the background (3) of a shot. Also called set light or dressing light.