Developed in the early years of the twentieth century, Autochromes were the result of the first commercially viable color photographic process. Yet the dyes used to impart the color in Autochromes are so sensitive to light that typical exhibition conditions cause rapid and irreversible fading, which has led to the Metropolitan Museum's policy of not exhibiting these vulnerable photographs. As the Museum's research scholar in photograph conservation, I spent three years studying the stability of Autochrome dyes. I began my research with a desire to better understand how and under what conditions Autochromes fade and, ideally, to devise a safe way to exhibit these important photographs. The exciting culmination of my work will take place next week, January 25–30, when five original Autochromes by Alfred Stieglitz and Edward Steichen will be displayed in low-oxygen enclosures as part of the special exhibition Stieglitz, Steichen, Strand.
The Autochrome was introduced in France in 1907 by Auguste and Louis Lumière—the same brothers who, in the 1890s, had created the earliest motion pictures. Their new color process was greeted with great enthusiasm by photographers, committed amateurs, and professionals alike, among them Alfred Stieglitz and Edward Steichen, the acknowledged leaders of the Pictorialist movement. Within months, Stieglitz and Steichen organized the first American exhibition of the Lumières' new process in New York. Members of the Pictorialist movement explored the Autochrome process with great creativity and interest, though by 1910 they gradually abandoned the technique. Even so, this short period saw the production of important early examples of color photography. Among the group of forty-five Autochrome plates in the Museum's collection are iconic images such as Steichen's Rodin–The Eve and his portrait of Alfred Stieglitz holding a copy of the journal Camera Work, which will both be on view next week.
What is it that makes the Autochrome image so unique and magical in its delicate color effects? What are the special qualities that, as with other early photographic processes such as the daguerreotype, we only see when we are able to look at originals? An Autochrome is a transparent color image on a glass support that must be viewed either with a transmitted light source or by projection in a specific device. The image is made up of a silver gelatin layer–like that used in the black-and-white photography of the time–together with a color screen of minuscule potato starch grains that are dyed red, green, and blue and filter the light during image capture, producing the color effect. The dyes used to tint the potato starch grains are very fugitive and tend to fade rapidly and irreversibly when exposed to light.
Working closely with Masahiko Tsukada of the Department of Scientific Research and under the supervision of Nora Kennedy, the Museum’s Sherman Fairchild Conservator of Photographs, I have conducted experiments that show that the fading of the color dyes in Autochrome images can be mitigated over short periods by enclosing the plates in a low-oxygen environment during display.
Oxygen-free, or anoxic, environments have been a subject of great interest to conservators recently, as it has been shown that the rate of deterioration from light exposure can sometimes be reduced, or even arrested, in an environment free of oxygen. The Met's 2007 exhibition of the beautifully restored panels of Ghiberti’s Gates of Paradise was possible because the bronze doors were displayed in custom-made anoxic cases. Likewise, the original manuscript of the Declaration of Independence is now exhibited at the National Archives in Washington, D.C., in an anoxic case. Despite well-known precedents, however, the application of low-oxygen environments to the display of photographic materials had not previously been explored.
My own interest in the influence of oxygen on the fading of dyes coincided with the desire of the curators in the Department of Photographs to show early color works from the collection. To establish how this could be done safely, I designed an experiment using samples of Autochrome dyes created in accordance with historic recipes. These samples were then systematically exposed to light under two conditions: in oxygen at environmental levels (around 21%) and in oxygen at low levels. I did this by placing the samples in plastic-capped glass tubes specially designed for the purpose. Some tubes had regular levels of oxygen, while others were purged with Argon, an inert gas that replaced the oxygen and nitrogen gases that are normally present in the air that we breathe. To absorb any residual oxygen, small tablets called “scavengers” were also placed in the purged tube before they were sealed, together with indicators capable of monitoring any oxygen ingress at levels as low as 0.01%.
The exposure to light of the complete set of tubes was carried out at the Image Permanence Institute of the Rochester Institute of Technology using an apparatus called a light-fading unit. Careful measurements were made of the intensity and tonality of the color of the samples both before and after exposure in the unit, a process that lasted several weeks. The results were dramatic and readily visible to the eye even as the samples in the tubes were being removed from the apparatus. It was clear that the Autochrome dyes had faded at a much lower rate in the absence of oxygen, making it possible to propose the display of original plates for a short period of time, on the condition that they be enclosed in a low-oxygen environment.
I am pleased that, as a result of my research, rare, original Autochromes from the Museum's collection will be on view to the public for the first time in recent history, protected in custom-designed, low-oxygen display units at carefully monitored light levels. From January 25 to January 30, 2011, visitors will be able to appreciate the beauty of five unique Autochromes by master photographers Alfred Stieglitz and Edward Steichen, temporarily replacing the facsimiles that will be displayed during the remaining weeks of the exhibition Stieglitz, Steichen, Strand.
Luisa Casella is a research scholar in photograph conservation in the Department of Photographs.
Exhibition: Stieglitz, Steichen, Strand
Heilbrunn Timeline of Art History: Alfred Stieglitz (1864–1946) and American Photography; Edward Steichen (1879–1973): The Photo-Secession Years
Department of Photographs
Science and Conservation