An editing technique and special effect that blends two or more shots (of separately photographed action) on the same film strip in such a way that the images are seen simultaneously. The technique of superimposition always draws attention to itself since it breaks up the apparent continuity of time and space. During a lap dissolve, one image is momentarily superimposed on another. In contrast, however, a superimposition usually lasts longer than the blending of two shots in a lap dissolve, and unlike a lap dissolve, usually does not signify a transition from one scene to another. Superimpositions are frequently used in montage sequences.
