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Autochrome Lumière
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The Autochrome Lumière is an early color photography process. Patented in 1903 by the Lumière brothers in France and first marketed in 1907, it remained the principal color photography process available until it was superseded by the advent of color film during the mid 1930s.
Manufacturing techniques
Autochrome is an additive color 'screen-plate' process: the medium contains a glass plate, overlaying random mosaic of microscopic grains of potato starch, with lampblack filling the space between grains, and an impermeable black-and-white, panchromatic silver halide emulsion.
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Encyclopedia
The Autochrome Lumière is an early color photography process. Patented in 1903 by the Lumière brothers in France and first marketed in 1907, it remained the principal color photography process available until it was superseded by the advent of color film during the mid 1930s.
Manufacturing techniques
Autochrome is an additive color 'screen-plate' process: the medium contains a glass plate, overlaying random mosaic of microscopic grains of potato starch, with lampblack filling the space between grains, and an impermeable black-and-white, panchromatic silver halide emulsion. The grains are a mixture of those dyed orange, green and violet, which act as color filters. The plate is processed as a slide — that is, the plate is first developed to a negative image and then reversed to a positive image — and the starch grains remain in alignment with the emulsion after processing in order to allow the colors to be seen properly.
.Source: The National Geographic Magazine, March 1921]]
To create the Autochrome plates, a slightly concave glass plate was coated with a mixture of pitch (crude pine sap), and beeswax. The starch grains, graded to between 5 and 10 micrometres in size, were coated on top of the plate. The exact methods by which they were coated still remain unclear, although it is known that approximately four million grains per square inch coated the filter in a single layer. It was later discovered that applying extreme pressure to the plate — around 5,00 kg/cm² — would improve the quality of the image, as the starch grains would be flattened slightly, reducing graininess and transmitting more light to the emulsion. Lampblack was then applied by a machine in order to fill the clear spaces between the grains. After this, the plate was coated with shellac. This served to protect the color mosaic and provided a flat surface for the emulsion, which was spread on the plate once the shellac dried.
The describes the process more generally: the grains can be orange, violet, and green, or red, yellow, and blue (or "any number of colors"), optionally with black powder filling the gaps.
Viewing techniques
Small autochromes could be viewed using a hand-held transparency viewer, but large ones required the use of a special device. Called a "Diascope", this was a flat case holding the autochrome image and a ground glass diffuser in one side, with a mirror positioned in the other. A user would let light pass through the autochrome and view the image in the mirror. Stereoscopic autochromes were particularly successful, the combined color and depth proving a bewitching experience to early 20th century eyes. Projectors, or "magic lanterns" as they were then known, were a less common but effective display technique, more commonly used for public viewing.
If an Autochrome is well made, color values can be very good. Unfortunately, the dyed starch grains are often somewhat coarse, giving a hazy effect with stray colors often appearing, especially in open light areas like skies. Nonetheless, this "dream-like", impressionist quality was a major reason behind the enduring popularity of the medium over a thirty-year period.
Although difficult to manufacture and relatively expensive, autochomes were relatively easy to use and were immensely popular amongst enthusiastic amateur photographers. However, they failed to sustain the initial interest of more serious "artistic" practitioners, largely due to their inflexibility. Not only did the need for diascopes and projectors make them extremely difficult to publicly exhibit, they allowed little in the way of the manipulation much loved by aficionados of the then-popular pictorialist approach.
Advent of photographic film
Autochromes continued to be produced as glass plates until the 1930s, when film-based versions were introduced, as Lumicolor in 1932, and Filmcolor in 1938. While it almost completely replaced glass-plate autochromes within three years, its success was short-lived, as manufacturers such as Kodak and Agfa began in earnest to produce the multi-layer, subtractive color films (such as Kodachrome, Agfacolor Neu and Kodacolor) which we know today.
Between 1909 and 1931 a collection of 72,000 autochrome photographs, documenting life at the time in 50 countries around the world, was created by French banker Albert Kahn. One of the biggest of its kind in the world, the collection is housed in The Albert-Kahn Museum on the outskirts of Paris.
In recent years, there has been a revival of interest in the process by some groups. Groups in France, working with the original Lumiere machinery and notes, and a few individuals in the United States, are attempting to recreate the process. Very few complete successes have resulted.
The 2006 film "The Illusionist," which was nominated for an Oscar for its cinematography, tried to recreate the look of autochrome.
Recently, this process was recreated by the photographer Frédéric Mocellin.
A new book containing a compilation of the Albert Kahn collection is expected to be published in 2008.
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