Broadwalk (1972)

Originally, this was a four-minute time-lapse film that was shot continuously over a twenty-four-hour period. The camera was positioned on a busy pathway in Regent's Park, and recorded three frames a minute. The shutter was held open for the twenty-second duration between exposures, so that on projection, individual frames merge together making the patterned flows of human movement clearly perceptible. The time-lapse original was then expanded by various processes of re-filming to reveal the frame-by-frame structure of the original. – William Raban