Definition & Meaning of "bipack"

What is "bipack"?

Bipack is a filmmaking technique where two separate layers of film stock are exposed simultaneously to create a specific visual effect. This is done by placing one piece of film on top of another in the camera, allowing both to be exposed to light at the same time. Bipack is often used to combine different visual elements, such as blending live action with special effects or creating unique color effects. This technique allows filmmakers to achieve complex images and effects that would be difficult or impossible to create with a single layer of film.