Filming & Production
Matte box
Also called: mattebox
A matte box does two jobs. Filter trays hold square or rectangular glass, ND, polarisers and diffusion, in front of the lens where they can be swapped or rotated without unscrewing anything, which matters when exposure changes between shots. French flags and side wings shade the front element from lights just outside the frame that would otherwise throw flare across the image or lift the contrast.
It is rig gear rather than something a solo creator needs. A matte box adds bulk, weight and setup time, and screw-in filters with a lens hood cover the same ground on a talking-head channel. On a lit shoot with frequent ND changes it saves real time; on a desk setup it is decoration.