The autochrome was
first patented in 1903 in France and 1906 in the United States by Auguste and
Louis Lumiere. The Lumiere brothers, who had already made a name for themselves
as early motion picture entrepreneurs with the cinematograph, turned their attention
to color photography around the turn of century (Lumiere.org, n.d.). Earlier
color photographic processes, such as the trichrome, required three separated
exposures through colored lenses that then needed to be superimposed to create a
full color image. The autochrome allowed color images to be taken in one long
exposure.
American Patent for the Autochrome 1906. Retrieved from http://www.google.com/patents?id=vytZAAAAEBAJ
Autochrome slides
were prepared by scattering millions of red, green, blue grains of potato
starch over a glass plate varnished with a mixture pine tar and beeswax. Lampblack,
a substance similar to soot, was used to fill in the gaps between the colored starch
particles. The grains were then covered with a shellac sealer to encapsulate
them and provide a clean surface for the orthochromatic silver gelatin bromide emulsion.
This plate was then loaded into the camera with the emulsion side facing away
from the lens, so that light would first pass through the colored particles (Friedman,
56). Because much of the light was blocked in the filtering process, the
exposure times were much longer than black and white photography of the day. After
exposure the plate was washed and developed just as any black and white glass
plate of the time. The negatives were treated in a chemical bath and exposed to
white light to redevelop the residual colored positive impression (Baldwin, 10).
Because of the colored filter and lampblack,
the image was extremely dark when viewed with just the naked eye. Thus the
autochrome was viewed one of two ways. Either with a devise called a diascope,
which used a mirror and sunlight to backlight the image, or a projector, which
ran the risk of heating up and damaging the autochrome. The striking image had
bold brilliant colors with a grainy affect similar to the pointillism technique
in painting.
Straus, N. [Autochrome portrait of Flora Stieglitz Straus] Yale Collection of American Literature, Beinecke Rare Book and Manuscript Library
As autochromes are
unique transparency images, great care must be taken to preserve both the
fragile glass and emulsion from heat, humidity, and physical damage (LOC,
n.d.). An autochrome’s stability may be compromised during digitization, and
the use of specialized equipment is needed to capture the original color
scheme. Autochromes, as well as other reflective photographic surfaces, should
be shot at a 45 degree angle to reduce glare, and in some cases a piece of
treated glass may be placed over the image to reduce Newton’s Rings.
References:
Autochrome. Retrieved February
26, 2013, from http://www.institut-lumiere.org/english/lumiere/autochrome.html
Baldwin, G. (1991) Looking at Photographs: A Guide to Technical
Terms. Malibu, California: J. Paul Getty Museum.
Deterioration and
Preservation of Autochromes. Retrieved February 27, 2013, from http://www.loc.gov/pictures/collection/agc/autochrome.html
Friedman, J. PhD. (1944) History of Color Photography. Boston:
The American Photographic Publishing Company.
Videos:
A brief history the autochrome
and the works of Heinrich Kuehn
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