Traveling-Matte Method

a method of combined filming that involves the use of an opaque silhouette (the traveling matte) of a moving actor or other object filmed on special masking film for the purpose of forming the complete image on each frame of the film by parts. The method makes it possible to obtain completely filmed sequences without sending the actors out on complicated expeditions and without the construction of expensive scenery; the method is also useful in the filming of apparently dangerous scenes.

There are many methods of obtaining a traveling matte. In the USSR, special infrachromatic film, sensitive to infrared rays, is extensively used for this purpose. One traveling-matte method was worked out by Mosfil’m and the Scientific Research Motion Picture Institute on the basis of proposals by the cameraman B. K. Gorbachev and the engineer V. I. Omelin. In this method, the filming process consists of two stages.

In the first stage, the actor is photographed simultaneously on two films: the usual negative film (black-and-white or color) and an infrachromatic one. The actor is placed in front of a special background that radiates only infrared rays in the direction of the apparatus. The actor himself is illuminated by white light from which a filter excludes infrared rays. A filter that lets through only infrared rays from the background is placed in front of the infrachromatic film. After filming, the infrachromatic film is processed by the reversal-development method, and an opaque silhouetted image of the actor on a completely transparent background—that is, a traveling matte—is obtained. A latent image of the actor is formed on ordinary negative film, which is not sensitive to infrared rays. This film is not developed.

The second stage consists in the filming or projected imprinting of the background of an acted scene—for example, a drawing, mock-up, or nature landscape—which is not to be visible through the negative image of the actor. For this purpose, the film with the traveling matte is superimposed on the previously exposed negative film (on the lens side) in such a way that the silhouetted and negative image of the actor completely coincide. The filming of the background takes place. After shooting, the negative film—with the combined image imprinted on it—is developed and printed in the usual manner.