What technique, essential for both the Vitascope and the Cinématographe, involved stopping the film momentarily during projection?

Answer

Intermittent movement

Intermittent movement was the necessary technique utilized by late 1890s projectors like the Vitascope to stop each frame momentarily in front of the light source and lens for clear projection before moving the next frame.

What technique, essential for both the Vitascope and the Cinématographe, involved stopping the film momentarily during projection?
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