Line describing a cone

"In Line Describing a Cone, the conventional primacy of the screen is completely abandoned in favour of the primacy of the projection event. According to McCall, a screen is not even mandatory. He succinctly describes the film: 'The viewer watches the film, by standing with his, or her, back towards what would normally be the screen, and looking along the beam towards the projector itself. The film begins as a coherent line of light, like a laser beam, and develops through the 30 minute duration into a complete, hollow cone of light.

The audience is expected to move up and down, in and out of the beam - this cannot be fully experienced by a stationary spectator. The shift of image as a function of shift of perspective is the operative principle of the film. External content is eliminated, and the entire film consists of the controlled line of light emanating from the projector; the act of appreciating the film-i.e., 'the process of its realisation'-is the content."
Deke Dusinberre, Studio International, Nov/Dec 1975..