Curtis Orthotone
Description
“In 1939 Thomas S. Curtis (1889–1964) proposed Orthotone, a dye imbibition printing method that was primarily a variation of the widely used Eastman Wash-Off Relief. Orthotone offered its practitioners complete control on the contrast or gradation of the print regardless of the contrast of the original negatives (Fig. 4.15). The underlying principle of the method was the simplification of the making of the matrices and the use of dyes that transferred quickly. According to Curtis (1939: 24), one complete color print could be made every twenty minutes with his method, the time it took to transfer only one dye with Kodak’s product. Printing was as follows. From the separation negatives, three enlargements were first printed on regular black-and-white photographic paper. Once the gradation scale of the prints was judged adequate, the matrices (made on Kodak or Defender material) were exposed one and a half times more than the prints and developed in Curtis’s Special Orthotone developer. The rest of the process was the same as with Eastman Wash-Off Relief, but with Orthotone dyes. In 1942 Curtis Permatone Dyes, with better spectral quality and permanence against light exposure, were introduced; these required only two to three minutes to transfer (Curtis 1947).”
(Pénichon, Sylvie (2013): Twentieth Century Colour Photographs. The Complete Guide to Processes, Identification & Preservation. London, Los Angeles: Thames & Hudson, on pp. 141–143.)
Secondary Sources
Pénichon, Sylvie (2013): Twentieth Century Colour Photographs. The Complete Guide to Processes, Identification & Preservation. London, Los Angeles: Thames & Hudson, on pp. 141–143. View Quote