slitscan

Slitscan is an imaging technique that encodes time into space by capturing a scene through a narrow slit as the scene or the slit itself moves. The final image is built from successive narrow exposures, so each vertical line (or strip) represents a different moment in time. The result is a time-stretched or warped representation of motion, often producing surreal or abstract shapes.

In practice, a slitscan setup uses a long, narrow opening in front of the image plane or a moving slit that exposes only a thin slice of the scene at any moment. The exposure is synchronized with the movement of the slit, the subject, or the film or sensor, so that a sequence of lines is assembled into a single frame. Variations include moving the slit across a stationary subject, moving the subject past a fixed slit, or using a rotating drum with a slit to sweep the image across a camera.

History and notable examples: Slitscan has roots in experimental photography and early cinema. It gained particular notoriety in science fiction cinema during the 1960s and 1970s, where it was used to create otherworldly light patterns. A famous application is the Star Gate sequence in 2001: A Space Odyssey (1968), which employed slit-scan photography to produce the characteristic elongated, flowing forms.

Modern usage and relation to other techniques: Today, slitscan continues in art, experimental video, and data visualization, often realized with digital simulations that sample lines from successive frames. It shares a conceptual kinship with rolling-shutter distortions in video, which can produce similar time-to-space effects when scanning occurs during motion, though slitscan is typically a deliberate creative or analytical process.