The slit-scan photography technique is a

photographic Photography is the art, application, and practice of creating durable images by recording light, either electronically by means of an image sensor, or chemically by means of a light-sensitive material such as photographic film. It is employed ...

and cinematographic process where a moveable slide, into which a slit has been cut, is inserted between the

camera A camera is an optical instrument that can capture an image. Most cameras can capture 2D images, with some more advanced models being able to capture 3D images. At a basic level, most cameras consist of sealed boxes (the camera body), with a ...

and the subject to be photographed. More generally, "slit-scan photography" refers to cameras that use a slit, which is particularly used in scanning cameras in

panoramic photography Panoramic photography is a technique of photography, using specialized equipment or software, that captures images with horizontally elongated fields of view. It is sometimes known as ''wide format photography''. The term has also been applied to ...

. This has numerous applications. This article discusses the manual artistic technique.{{cite web, url=https://petapixel.com/2017/10/18/role-slit-scan-image-science-art/, title=The Role of the Slit-Scan Image in Science and Art, date=18 October 2017, website=petapixel.com

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 Animation is a method by which still figures are manipulated to appear as moving images. In traditional animation, images are drawn or painted by hand on transparent celluloid sheets to be photographed and exhibited on film. Today, most ani ...

. It enables the cinematographer to create a

psychedelic Psychedelics are a subclass of hallucinogenic drugs whose primary effect is to trigger non-ordinary states of consciousness (known as psychedelic experiences or "trips").Pollan, Michael (2018). ''How to Change Your Mind: What the New Science ...

flow of colors. Though this type of effect is now often created through computer animation, slit-scan is a mechanical technique. John Whitney developed it for the opening credits of the Hitchcock film ''

Vertigo Vertigo is a condition where a person has the sensation of movement or of surrounding objects moving when they are not. Often it feels like a spinning or swaying movement. This may be associated with nausea, vomiting, sweating, or difficulties ...

''. After he sent some test sequences on film to

Stanley Kubrick Stanley Kubrick (; July 26, 1928 – March 7, 1999) was an American film director, producer, screenwriter, and photographer. Widely considered one of the greatest filmmakers of all time, his films, almost all of which are adaptations of nove ...

, the technique was adapted by

Douglas Trumbull Douglas Hunt Trumbull (; April 8, 1942 – February 7, 2022) was an American film director and innovative visual effects supervisor. He pioneered methods in special effects and created scenes for '' 2001: A Space Odyssey'', ''Close Encounters ...

for '' 2001: A Space Odyssey'' in 1968 for the "star gate" sequence which required a custom-built machine. 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 John Devon Roland "Jon" Pertwee (; 7 July 1919 – 20 May 1996) was an English actor, comedian, entertainer, cabaret performer and TV presenter. Born into a theatrical family, he served in the Royal Navy and the Naval Intelligence Division during ...

and

Tom Baker Thomas Stewart Baker (born 20 January 1934) is an English actor and writer. He is well known for his portrayal of the fourth incarnation of the Doctor in the science fiction television series '' Doctor Who'' from 1974 to 1981.Scott, Danny. ( ...

used between December 1973 and January 1980. Slit-scan was also used in '' Star Trek: The Next Generation'' (1987–1994) to create the "stretching" of the starship ''Enterprise''-D when it engaged

warp drive A warp drive or a drive enabling space warp is a fictional superluminal spacecraft propulsion system in many science fiction works, most notably ''Star Trek'', and a subject of ongoing physics research. The general concept of "warp drive" was i ...

. Due to the expense and difficulty of this technique, the same three warp-entry shots, all created by

Industrial Light and Magic Industrial Light & Magic (ILM) is an American motion picture visual effects company that was founded on May 26, 1975 by George Lucas. It is a division of the film production company Lucasfilm, which Lucas founded, and was created when he began pro ...

for the series pilot, were reused throughout the series virtually every time the ship went into warp. Slit-scan photography was also used on '' Interstellar'' for scenes in the

tesseract In geometry, a tesseract is the four-dimensional analogue of the cube; the tesseract is to the cube as the cube is to the square. Just as the surface of the cube consists of six square faces, the hypersurface of the tesseract consists of ei ...

at the end of the movie.

Description

Stevemann selfportrait home-made slit-shutter camera1992

Slit-scan is an animation created image by image. Its principle is based upon the camera’s relative movement in relation to a

light source Light or visible light is electromagnetic radiation that can be perceived by the human eye. Visible light is usually defined as having wavelengths in the range of 400–700 nanometres (nm), corresponding to frequencies of 750–420 terah ...

, combined with a long

exposure Exposure or Exposures may refer to: People * The Exposures, a pseudonym for German electronic musician Jan Jeline Arts, entertainment, and media Films * ''Exposure'' (film), a 1932 American film * ''Exposure'', another name for the 1991 movie ...

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.

References

External links

Example code to create slit-scans

Unwrapping the 2001 Slit Scan sequences

ABC Movie of the Week opening sequence, created in 1969

Total Recall (1990) main title sequence

A Slit-Scan camera you can use through your web browser

Convert video to a Slit-Scan image (free program).
Special effects Photographic techniques