Continuity editing

Continuity editing is the process, in film and video creation, of combining more-or-less related shots, or different components cut from a single shot, into a sequence so as to direct the viewer's attention to a pre-existing consistency of story across both time and physical location. Often used in feature films, continuity editing, or "cutting to continuity", can be contrasted with approaches such as montage, in which the editor aims to generate, in the mind of the viewer, new associations among the various shots which can then be of entirely different subjects, or at least of subjects less closely related than would be required for the continuity approach.

Continuity editing can be divided into two categories: temporal continuity and spatial continuity. Within each category, specific techniques will work against a sense of continuity. In other words, techniques can cause a passage to be continuous, giving the viewer a concrete physical narration to follow, or discontinuous, causing viewer disorientation, pondering, or even subliminal interpretation or reaction, as in the montage style.

The important ways to preserve temporal continuity are avoiding the ellipsis, using continuous diegetic sound, and utilizing the match on action technique.

An ellipsis is an apparent break in natural time continuity as it is implied in the film's story. The simplest way to maintain temporal continuity is to shoot and use all action involved in the story's supposed duration whether it be pertinent or not. It would also be necessary to shoot the whole film in one take in order to keep from having to edit together different shots, causing the viewer's temporal disorientation. However, in a story which is to occupy many hours, days, or years, a viewer would have to spend too long watching the film. So although in many cases the ellipsis would prove necessary, elimination of it altogether would best preserve any film's temporal continuity.

Diegetic sound is that which is to have actually occurred within the story during the action being viewed. It is sound that comes from within the narrative world of a film (including off-screen sound). Continuous diegetic sound helps to smooth temporally questionable cuts by overlapping the shots. Here the logic is that if a sonic occurrence within the action of the scene has no breaks in time, then it would be impossible for the scene and its corresponding visuals to be anything but temporally continuous.

Match on action technique can preserve temporal continuity where there is a uniform, unrepeated physical motion or change within a passage. A match on action is when some action occurring before the temporally questionable cut is picked up where the cut left it by the shot immediately following. For example, a shot of someone tossing a ball can be edited to show two different views, while maintaining temporal continuity by being sure that the second shot shows the arm of the subject in the same stage of its motion as it was left when cutting from the first shot.

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