Niagara Custom Lab performs the E6 process for colour reversal stock on a modified Hills Mini-Mat 30, originally designed for the processing of slide film. A reel of film (S8, 16mm, or 35mm), spliced together using a handheld industrial stapler, is loaded into a magazine in the dark. The film passes through multiple tanks in a dark box before entering the “daylight” side of the lab just prior to the Pre-Bleach stage. Time in the tanks is determined by the number of rollers the film passes over and varies from tank to tank. Film travels from the magazine to the takeup reel in roughly an hour. A full reel of 600’ requires up to five hours, by far the longest discrete process in the lab.

Chemicals for the E6 process are purchased from Fuji in Japan at great expense and must be constantly replenished and aerated in the tanks to promote longevity. Colour developer, in particular, has the shortest shelf-life of any process chemical in the lab. The machine needs to be run at least once a week to season the tank, as well as prevent chemical exhaustion and general degradation. Because of fluctuating demand and supply, the lab has on occasion run the process for a single cartridge of Super 8, or 50' of film.

Colour reversal, or colour film which renders a positive image, is arguably synonymous with consumer-grade motion picture film cameras. Kodachrome and Ektachrome, Kodak’s two defining colour reversal stocks, are no longer in production. Kodachrome died long ago, obsolescence ensured by its complex and costly process. Early versions of Ektachrome met the same fate. (These stocks can occasionally be processed successfully as black and white negative.)

Later versions of Ektachrome, as well as lesser known "television" stocks, can be processed E6 and were stockpiled by prescient filmmakers when Kodak announced that it was ceasing production. Cartridges and spools of Ektachrome continue to trickle onto the lab's shelves, and Kodak has recently announced that it is developing a new version of Ektachrome, with plans for release in late 2017.

However, most of the colour reversal the lab sees is Agfachrome, also known as Wittner-Chrome, a blunter emulsion with notably chunkier grain and a somewhat greener colour cast, originally designed for aerial photography. Though it is the only remaining commercially available colour reversal stock, it is in fact no longer in active production. Cartridges and 16mm spools are cut down on-demand from a dwindling supply.

No colour reversal motion picture stock is currently in production. This machine processes motion picture emulsions that are all but extinct.


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Special thanks to Jen Heuson, Kevin T. Allen, Maile Colbert, Ernst Karel, Peter McMurray, Zach Poff, Benjamin Tausig and participants of the Sound Ethnographies workshop at UnionDocs. Also indebted to the guidance and expertise of Sylvain Chaussee and Sebastjan Henricksen.