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Ub Iwerks - quotes

Quotations relating to Ub Iwerks...

Film Post-Production

The blue screen process, while it had been essentially perfected in 1958, was still not quite to the level that Hitchcock wanted. And the best examples of travelling matte work in general that Hitchcock had seen was the sodium travelling matte shot process that was used primarily at the Disney studio.

The sodium process was a method of combining foregrounds and backgrounds that were photographed at different times in an optical printer in post production. At some point, you have to create a matte, or a silhouette, that enables you to distinguish photographically between the foreground, which is usually an actor against a screen, and the background. In the sodium process, the background was illuminated by yellow sodium light. Of course, the actors in the foreground were illuminated by white light. There were two films in a special camera, an old Technicolor camera. One film was sensitive only to the sodium light on the backing. The second film in the camera was sensitive only to the white light falling on the actors. As a result, there was absolutely no contamination of the foreground actors by the lighting from the background.

Typical of blue screen shots of the period was a sort of blue fire in hair and on the edges of objects. And the sodium light, because there literally was no light from the backing on the actors at any time, the sodium system could produce a higher-quality composite that didn't exhibit the sort of blue flare and blue halos that were sometimes seen on blue screen composites of the day. Disney had brought the sodium process to a high level of perfection, and Ub Iwerks, who was the head of the Disney special processes department, was hired as a consultant, and the Disney sodium equipment was used to create the travelling matte shots on "The Birds".

Bill Taylor (2000)
keywords: Alfred Hitchcock, Technicolor, The Birds (1963), Ub Iwerks, Walt Disney, post-production, special effects, and the sodium process