Slit-scan photography
Encyclopedia
The slit-scan photography technique is a photographic
and cinematographic
process where a moveable slide, into which a slit has been cut, is inserted between the camera
and the subject to be photographed.
during the production of Stanley Kubrick
's 2001: A Space Odyssey
and used extensively in the "stargate" sequence. It requires an imposing machine, capable of moving the camera and its support. This type of effect was revived in other productions, for films and television alike. For instance, slit-scan was used by Bernard Lodge
to create the Doctor Who
title sequences for Jon Pertwee
and Tom Baker
used between December 1973 and 1979. Slit-scan was also used in Star Trek: The Next Generation
to create the "stretching" of the starship Enterprise-D when it engaged warp drive
. Due to the expense and difficulty of this technique, the same three warp-entry shots, all created by Industrial Light and Magic
for the series pilot, were reused throughout the series virtually every time the ship went into warp.
created image by image. Its principle is based upon the camera’s relative movement in relation to a light source, combined with a long exposure
time. The process is as follows:
Naturally, this effect is very time-consuming, and thus expensive, to create. A 10-second sequence at 24 frames per second requires a minimum of 240 adjustments.
Photography
Photography is the art, science and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor or chemically by means of a light-sensitive material such as photographic film...
and cinematographic
Cinematography
Cinematography is the making of lighting and camera choices when recording photographic images for cinema. It is closely related to the art of still photography...
process where a moveable slide, into which a slit has been cut, is inserted between the camera
Camera
A camera is a device that records and stores images. These images may be still photographs or moving images such as videos or movies. The term camera comes from the camera obscura , an early mechanism for projecting images...
and the subject to be photographed.
Use in cinematography
Originally used in static photography to achieve blurriness or deformity, the slit-scan technique was perfected for the creation of spectacular animations. It enables the cinematographer to create a psychedelic flow of colors. Though this type of effect is now often created through computer animation, slit-scan is a mechanical technique. It was adapted for film by Douglas TrumbullDouglas Trumbull
Douglas Huntley Trumbull is an American film director, special effects supervisor, and inventor. He contributed to, or was responsible for, the special photographic effects of 2001: A Space Odyssey, Close Encounters of the Third Kind, Star Trek: The Motion Picture, Blade Runner and The Tree of...
during the production of Stanley Kubrick
Stanley Kubrick
Stanley Kubrick was an American film director, writer, producer, and photographer who lived in England during most of the last four decades of his career...
's 2001: A Space Odyssey
2001: A Space Odyssey (film)
2001: A Space Odyssey is a 1968 epic science fiction film produced and directed by Stanley Kubrick, and co-written by Kubrick and Arthur C. Clarke, partially inspired by Clarke's short story The Sentinel...
and used extensively in the "stargate" sequence. It requires an imposing machine, capable of moving the camera and its support. This type of effect was revived in other productions, for films and television alike. For instance, slit-scan was used by Bernard Lodge
Bernard Lodge
Bernard Lodge is a British designer best known for his work on the BBC television series Doctor Who. He designed the first four series logos, and designed and engineered the first five title sequences. These include the 'howlaround' versions and the 'slit-scan' time tunnel ones...
to create the Doctor Who
Doctor Who
Doctor Who is a British science fiction television programme produced by the BBC. The programme depicts the adventures of a time-travelling humanoid alien known as the Doctor who explores the universe in a sentient time machine called the TARDIS that flies through time and space, whose exterior...
title sequences for Jon Pertwee
Jon Pertwee
John Devon Roland Pertwee , was an English actor. Pertwee is best known for his role in the BBC science fiction television series Doctor Who, in which he played the third incarnation of the Doctor from 1970 to 1974, and as the title character in the series Worzel Gummidge...
and Tom Baker
Tom Baker
Thomas Stewart "Tom" Baker is a British actor. He is best known for playing the fourth incarnation of the Doctor in the science fiction television series Doctor Who, a role he played from 1974 to 1981.-Early life:...
used between December 1973 and 1979. Slit-scan was also used in Star Trek: The Next Generation
Star Trek: The Next Generation
Star Trek: The Next Generation is an American science fiction television series created by Gene Roddenberry as part of the Star Trek franchise. Roddenberry, Rick Berman, and Michael Piller served as executive producers at different times throughout the production...
to create the "stretching" of the starship Enterprise-D when it engaged warp drive
Warp drive (Star Trek)
Warp drive is a faster-than-light propulsion system in the setting of many science fiction works, most notably Star Trek. A spacecraft equipped with a warp drive may travel at velocities greater than that of light by many orders of magnitude, while circumventing the relativistic problem of time...
. Due to the expense and difficulty of this technique, the same three warp-entry shots, all created by Industrial Light and Magic
Industrial Light and Magic
Industrial Light & Magic is an Academy Award-winning motion picture visual effects company that was founded in May 1975 by George Lucas and is owned by Lucasfilm. Lucas created the company when he discovered that the special effects department at 20th Century Fox was shut down after he was given...
for the series pilot, were reused throughout the series virtually every time the ship went into warp.
Description
Slit-scan is an animationAnimation
Animation is the rapid display of a sequence of images of 2-D or 3-D artwork or model positions in order to create an illusion of movement. The effect is an optical illusion of motion due to the phenomenon of persistence of vision, and can be created and demonstrated in several ways...
created image by image. Its principle is based upon the camera’s relative movement in relation to a light source, combined with a long exposure
Exposure (photography)
In photography, exposure is the total amount of light allowed to fall on the photographic medium during the process of taking a photograph. Exposure is measured in lux seconds, and can be computed from exposure value and scene luminance over a specified area.In photographic jargon, an exposure...
time. The process is as follows:
- An abstract colored design is painted on a transparent support
- This support is set down on the glass of a backlighting table and covered with an opaque masking into which one or more slits have been carved.
- The camera (placed high on top of a vertical ramp and decentered in relation to the light slits) takes a single photograph while moving down the ramp. The result: at the top of the ramp, when it is far away, the camera takes a rather precise picture of the light slit. This image gets progressively bigger and eventually shifts itself out of the frame. This produces a light trail, which meets up with the edge of the screen.
- These steps are repeated for each image, lightly peeling back the masking, which at the same time produces variation in colors as well as variation of the position of the light stream, thus creating the animation.
Naturally, this effect is very time-consuming, and thus expensive, to create. A 10-second sequence at 24 frames per second requires a minimum of 240 adjustments.
External links
- Example code to create slit-scans
- Slit-Scan Photography
- Unwrapping the 2001 Slit Scan sequences
- Video of the 1973 Doctor Who title sequence, which used this technique
- Video of the 1974 Doctor Who Slit-Scan title sequence
- An Informal Catalogue of Slit-Scan Video Artworks
- ABC Movie of the Week opening sequence, created in 1969
- Total Recall (1990) main title sequence