Slit-Scan Photography: An Abstract Stop-Motion Animation Technique

By Sam Komer and Asher Young

Digital slit scans (Frederic 1980)

 

Slit-scan photography is a frame-by-frame photographic and cinematographic technique that involves the placement of a slit in between a moving stop-motion camera and its subject during a long exposure. The process results in an image that appears stretched, abstracted, or distorted. In photographic form, slit-scan technology originated in the 1850s with the invention of the first panoramic cameras in Europe, which were created for mapping and other scientific uses. The technology was later adapted for use in horse and car race finish photography in the 1940s and 50s, the slit scanning the image across a horizontally-transported film strip. In film and television, slit-scan photography was first used in the 1960s, and has historically been associated with science-fiction media, some notable examples being in 2001: A Space Odyssey (1968, dir. Stanley Kubrick),  Star Trek: The Next Generation (1987, Gene Roddenberry), Doctor Who (1963, Sidney Newman, C.E. Webber, Donald Wilson), and Interstellar (2014, dir. Christopher Nolan).

Drawing upon the technology of panoramic cameras and race finish photography, the technique is a uniquely mechanical and analog process (though it may be digitally emulated nowadays). Cinematic slit-scan comprises a few key elements: a camera with a stop-motion shutter, a screen with a thin slit, and a transparent subject. The effect is created frame-by-frame as the subject is backlit. A single frame is exposed over several seconds, while the camera is moved towards or away from the subject. The camera’s position is then reset before the next exposure. Its gradual change relative to the slit distorts the shape of the object seen through it, making it appear to stretch into a wall of color as it enlarges in the frame. Importantly, the slit is not centered relative to the camera, but is slightly offset to create distinct “walls,” rather than an enlarging bar in the center of the frame– exposures are thus taken twice, with alternating slit positions, in order to create a double wall. This effect was first created by animator John Whitney, who developed it for the opening credits of Alfred Hitchcock’s film Vertigo (1958), and was built upon by Douglas Trumbull while he was working on 2001: A Space Odyssey. Trumbull’s setup was made up of an electronic dolly, a stop-motion camera, and two large glass panes, one with a slit, and one painted with abstract artwork. This was set up so that Trumbull could precisely move both the camera and subject at the same time during an exposure– the added dimension of the subject’s movement heightened the effect by further abstracting and distorting the result.

The famous “Star-gate” sequence from Stanley Kubrick’s 2001: A Space Odyssey remains one of the most iconic scenes in science fiction, even over 50 years later. It also displays one of the earliest and most well-known uses of slit-scan photography techniques within cinema. Special effects for this film were done by Douglas Trumbull, whose inspiration for using these techniques was Kubrick’s desire to see the camera “go through something” (Trumbull 1969, 998). The aesthetic of this film “was meant to support Kubrick’s intention to present it as a “science speculation” film, not as science fiction” (Turnock, 2015, 71). Slit scan is often used in film to create abstract and colorful intro sequences, including the Dr. Who warped tunnel and the Vertigo opening credits featuring spiral shapes flying at the camera. Commonly seen in science fiction or psychological genres, these psychedelic sequences of color and motion are a unique form of animation that gives opportunity for abstracted visuals beyond what live-action materials can do. Both are displays of light and color, but slit scan is animation done frame by frame. Before this style appeared in cinema, slit scan techniques originated in panoramic photography in the 19th century. Panoramics were used largely to take landscape photos that were too vast to be captured in a single static frame. Both slit scan and panoramics distort the images, giving them a disfigurement that isn’t seen in traditional photography. Notable panoramic photographers include George Barnard, who took photos of military fortresses during the Civil War, and William J. Johnston, who patented the Cirkut panoramic camera in 1904, which became extremely popular with commercial photographers.

With modern technology, slit scan was developed to be used digitally. For example, editing software such as Adobe After Effects allows users to manipulate already existing videos to warp the subjects into new still images (Andreev 2016). Many photographers today use slit scan for their own craft. Even with new technologies accessible, the use of film cameras is still alive and well. And many artists prefer it because “A handmade print has a totally different feel,” according to Italian artist and filmmaker Paolo Gioli (Antonini 2015). Other photography methods we see used today that are remnant of slit scan techniques include light trail photography. The main difference is that in this method, the shutter only closes once, rather than many times, to create one image. But both methods experiment with camera exposure to capture distorted images using movement and light.

 

Bibliography:

“A Brief History of Panoramic Photography | Articles and Essays | Panoramic Photographs | Digital Collections | Library of Congress.” n.d. The Library of Congress. https://www.loc.gov/collections/panoramic-photographs/articles-and-essays/a-brief-history-of-panoramic-photography/.

Andreev, Andre. “How to Create the ‘2001’ Slit Scanning Effect with Digital Tools.” nofilmschool. Nov 3, 2016. https://nofilmschool.com/2016/11/how-to-create-2001-slit-scanning-effect

Antonini, Marco. Experimental photography: a handbook of techniques. Thames & Hudson Inc., 2015.

Jung, Stefan. “The Visual Peak: Saul Bass as Hitchcock’s ‘Pictorial Consultant’” Reassessing the Hitchcock Touch (2017): 153-169 https://doi.org/10.1007/978-3-319-60008-6_9

Levitan, Eli L. Handbook of Animation Techniques. New York, New York: Van Nostrand Reinhold Co., 1979.

Parke, Frederic, “ADAPTATION OF SCAN AND SLIT-SCAN TECHNIQUES TO COMPUTER ANIMATION”, Computer Graphics Vol. 14 No. 3 (1980): 178-181 https://dl.acm.org/doi/pdf/10.1145/800250.807489

Ryan, Kristen. 2020. NIGHT PHOTOGRAPHY PART 3: LIGHT TRAILS. https://kristenryanphotography.com/blog/2020/6/25/night-photography-part-3-light-trails

Trumbull, Douglas, “The Slit-scan Process As Used In “2001: A SPACE ODYSSEY”-And Beyond …”, American Cinematographer International Journal of Motion Picture Photography and Production Techniques Vol. 50 No. 10 (1969): 998-1026 https://cdn.theasc.com/AMERICAN_CINEMATOGRAPHER_VOL.50_1969_10.pdf

Turnock, Julie. Plastic Reality: Special Effects, Technology, and the Emergence of 1970s Blockbuster Aesthetics. Columbia University Press, 2015.

TIFF Originals. “DOUGLAS TRUMBULL | Master Class | Higher Learning.” YouTube, 2012. https://www.youtube.com/watch?v=FBaZQojd1_s