One of the more unusual developments of film used for motion pictures was slit photography, where an image was created using a camera with a narrow shutter that captured light over a span of time. Some of the more conventional uses of this technology included panoramic photography, where the camera was synched to rotate as the film was pulled across the open shutter. Another use of slit photography was in the field of sports, where it was used to accurately record images at the finish lines of car and horse races to confirm the very close winners. With the use of a camera positioned exactly at the finish line, film was pulled across the open shutter with the result being a series of elongated shapes which appeared as elongated distortions. Some of the more innovative sports photographers such as George Silk http://www.sportsshooter.com/news/2043 noticed the bizarre shapes and forms of slit photography and created feature photo essays for magazines. The special effects supervisor Douglas Trumbull used similar equipment for the final stargate sequence in Stanley Kubrick movie film, 2001: A Space Odyssey. https://filmmakeriq.com/courses/history-science-slit-scan-effect-used-2001-space-odyssey/ As time went on, it appeared as a standard technique in the Dr. Who title sequence and other sci-fi presentations. It’s a good thing someone discovered the novelty of slit photography, because it helped to generate a feature in the Adobe’s After Effects software called Time Displacement. https://filmmakeriq.com/courses/create-bizarre-slit-scan-video/ Essentially, a grayscale image is used to displace the timing of a moving image, so that white areas go slow and black areas go fast. In the gray areas between, the familiar stretching effect of the slit scan photography emerges. One skill with this technique is in being able to generate a grayscale image that creates the desired results. After working with this feature for several weeks, I created this series of time displacement videos called Bonn which are slow moving panoramic views of the city in Germany set to fragments of music by Beethoven. Like watching the clouds roll by on a summer day, the videos use a specific grayscale map for each piece to influence the distortion and warping.