Footage a length of exposed motion-picture film iris-in an effect usually functioning as a transition between shots in which the image is initially dark, then a widening opening-often a circle or an oval- reveals more and more of the next image, usually until it is fully revealed iris-out an effect usually functioning as a transition between shots in which the image is closed out as a constricting opening-usually a circle or an oval-closes down on it jump cut a transition between shots that causes a jarring or even shocking shift in space, time, or action lap dissolve a transition between shots in which one shot begins to fade out as the next shot fades in, overlapping the first shot before replacing it master shot a shot usually made with a wide-angle lens that records an entire scene match cut a transition between two shots in which an object or movement (or both) at the end of one shot closely resembles (or is identical to) an object or movement (or both) at the beginning of the next shot montage a technique in film editing in which a series of short shots are edited into a sequence to condense space, time, and information.

A history of narrative film 4th edition