Douglass Color No. 1
“This two-color additive system for color cinematography was invented in 1916 by Leon Forrest Douglass of San Rafael, California. A special beam splitter camera would advance each roll of film two frames per exposure with its double frame pull down mechanism. Roll A would thus be exposed behind a red filter, resulting in a red separation negative with alternate frames completely clear. Likewise, roll B would be exposed behind a green filter with only every other frame carrying a latent green image. These negatives were then printed onto normal black and white print film producing a continuous print with alternate frames containing an image from each of the camera negatives. After processing, the release prints were projected additively through a rotating shutter that contained a red filter in one opening and a green filter in the other. As with Kinemacolor, these prints were projected at 32 frames per second.
A public demonstration was given on February 14, 1918, at the Wurlitzer Fine Arts Hall, 120 West Forty-first Street, New York City.“
(Nowotny, Robert A. (1983): The Way of All Flesh Tones. A History of Color Motion Picture Processes, 1895-1929. New York: Garland Pub., p. 129.)
Cherchi Usai, Paolo (2000): Silent Cinema. London: BFI, p. 35.
Nowotny, Robert A. (1983): The Way of All Flesh Tones. A History of Color Motion Picture Processes, 1895-1929. New York: Garland Pub., pp. 129-131.
Ryan, Roderick T. (1977): A History of Motion Picture Color Technology. London: Focal Press, pp 30-32.
Theisen, Earl (1936): Notes on the history of color in motion pictures. In: International Photographer, Vol. 8, No. 5, June 1936, pp. 8-9 and p. 24, on p. 9.
Kelley, William Van Doren (1918): Natural Color Cinematography. In: Transactions of the Society of Motion Picture Engineers, 7, Nov. 1918, pp. 38–43, on p. 42.