Mark Osterman
2008, 5 August
Frederic Ives Additive Color Projection - Combined image from red and green filters

Magic lantern slide
George Eastman Museum
Courtesy of George Eastman House
 
Ives Additive Color Projection
 
Demonstrated Tuesday, August 5th 2008 George Eastman House, Rochester, NY
 
Maxwell's 1861 demonstration of projected additive color photography was hampered by the limitations of ordinary UV, violet and blue sensitive wet collodion negatives. By the time Frederic Ives (Phila) presented the same demonstration in the 1880s, dyes were being used to sensitive both collodion bromide and gelatin bromide negative plates to a wider range of spectral sensitivity. While fully panchromatic plates were not produced until 1906, Ives was able to make plates sensitive to violet blue, green and orange by combining chlorophyll and eosin.
 
Ives made his exposures using a camera of his own design. This made three separate exposures on the same plate through orange red, violet blue and green filters. The negatives were developed and then contact printed onto a second plate to produce a silver bromide positive image. These three positives were cut apart and carefully mounted in a wood frame for inserting into a special three lens projector fitted with the three color filters. The Ives projector was a didactic tool; adjustable to allow separation or coincidence the images by the movement of a lever.
 
In this demonstration, three separate magic lantern projectors were used to project three black and white positive transparencies through orange red, green and violet blue filters. The pictures included here illustrate the three filtered images apart and also upon each other to create a virtual full color image. The three glass positive lantern slides were made by Mark Osterman using a gelatin bromide emulsion formula of the 1880s. Osterman used the original glass separation negatives made by Frederic Ives to produce the positives.
 
Mark Osterman
 
Process Historian
Center for the Legacy of Photography
George Eastman House International Museum of Photography and Film Rochester, NY
 
LL/29900