A Slice through time: Slit–scan Art

Watching the sky – Mitchell Whitelaw

While at Node08, Joreg, one of the brains behind VVVV, demonstrated a nice patch to simulate the photographic and filmmaking process of slit scanning. It was pleasing to see the holy grey V4 teapot become stretched and contorted through a synthetic space-time continuum. The patch he demonstrated (Timewarp) is available on his user page.

The technique, which has been widely used by artists, involves taking small photographic slices (slits) of an image and then stitching the strips together to provide a time based image – a record of whole series of events, rather than a single snapshot. It turns out that Golan Levin has provided us with excellent overview of the technique with a large list of artworks that have employed this process including ones utilising digital media techniques. He also provides us with Processing and Flash source files that utilise slit-scan simulations to process images via web cams.

Probably one of the most memorable moving image slit-scan moments is the Stargate sequence in the movie 2001, A Space Odyssey. The making of the sequence is often attributed to Douglas Trumball, although research seems to suggest that there was much larger team involved in reality (including Tom Howard, Con Pederson, and Wally Veevers). The plot thickens a little more as it appears from essays by William Moritz, a respected expert in the field of Visual Music, that it was none other that John Whitney (see previous post) who originally approached Kubrick with the idea of using slit-scan special effects in the movie. He was turned down. Whitney seems to have discovered a version of the slit-scan technique via the malfunctioning of one of his own custom built mechanical computers. He used the technique his film Catalogue, made in 1961.

Radial positioning of image slits into circular forms provides a nice way of presenting a days worth of event information in a way analogous to the circularity of clock or cycle of the sun relative to the earth. Mtchl’s ‘Watching the sky’ Flickr set contains images where ‘Segments of the datasets are visualised, compressing time and revealing spatial and temporal patterns in the environment’.

Oli Laurelles ‘Travelling Around’ project captures images during train journeys and then squeezes the pictures into a series of 1 pixel wide snapshots. When stitched together radially they represent abstract visualisations of passages through time. They further give a clear indication not only of location but also the speed of the train at any particular moment in the journey.