“Coloratura. This is the process of Pathé Exchange at Bound Brook, N. J. Negatives are made by the bi-pack method. Prints are made on double-sided film and are dye-toned on one side and metallic-toned on the other. The double-sided film, having two developed silver images is first treated on one side to make it dye-selective and from then on the film is totally submerged to receive both colors, the blue-green tone on one side and red dye on the opposite side, neither color going to the wrong side. The film is treated by machinery so that the work is completed in a single trip of the film through the device.”
(Report of the Color Committee. In: Journal of the Society of Motion Picture Engineers. July 1931, p. 116.)
Original Technical Papers and Primary Sources
Society of Motion Picture Engineers (1931): Report of the Color Committee. In: Journal of the Society of Motion Picture Engineers. July 1931, p. 116.
Eggert, John (1932): Kurzer Überblick über den Stand der Farbenkinematographie. In: Bericht über den VIII. Internationalen Kongress für wissenschaftliche und angewandte Photographie, Dresden 1931. Leipzig: J. A. Barth, pp. 214–221, on pp. 215–218. (in German)
Klein, Adrian Bernhard = Cornwell-Clyne (1940): Colour Cinematography. Boston: American Photographic Pub. Co., 2nd revised edition, p. 210.
Nowotny, Robert A. (1983): The Way of All Flesh Tones. A History of Color Motion Picture Processes, 1895-1929. New York: Garland Pub., p. 271.
Ryan, Roderick T. (1977): A History of Motion Picture Color Technology. London: Focal Press, pp 99.