Split screen (filmmaking)

In film and video production, split screen is the visible division of the screen, traditionally in half, but also in several simultaneous images, rupturing the illusion that the screen's frame is a seamless view of reality, similar to that of the human eye. There may or may not be an explicit borderline. Until the arrival of digital technology in the early 1990s, a split screen was accomplished by using an optical printer to combine two or more actions filmed separately by copying them onto the same negative, called the composite.

In filmmaking split screen is also a technique that allows one actor to appear twice in a scene. The simplest technique is to lock down the camera and shoot the scene twice, with one "version" of the actor appearing on the left side, and the other on the right side. The seam between the two splits is intended to be invisible, making the duplication seem realistic.

Several studio-made films in the 1960s popularized the use of split screen. They include Indiscreet (1958), John Frankenheimer's Grand Prix (1966), Richard Fleischer's The Boston Strangler (1968), Norman Jewison's The Thomas Crown Affair (1968), Airport (1970), (1970), The Andromeda Strain (1971), Carrie (1976) and More American Graffiti (1979).

In "Indiscreet" the technique was famously used to bypass the censors and allow Cary Grant and Ingrid Bergman to be in bed together, and even to appear to pat her on the bottom.

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