Mark Osterman

ROBERT | Mark, you are the Photographic Process Historian at the George Eastman House International Museum of Photography and Film. In your job, you researched and then recreated the evolution of photographic processes based on original writings and examples from the museum, and later taught these processes to the general public. How were you introduced to photography, and how did you finally end up at the museum?

MARK | Actually, my job at the museum was initially to teach photograph conservators how to identify early photographic processes. This also included how to determine the difference between a well-made photographic image in poor condition compared to a poorly made image in good condition.

My father originally introduced me to conventional silver based photography when I was a boy. He helped me put together a little darkroom in the dirt floor basement of our eighteenth century farm house in Pennsylvania. By the time I was in high school, I already owned several antique ambrotypes, but had no idea how they were made until I started my own research in the mid-1980s while I was teaching photography in a private high school.

By the time I met France in 1990, I was making collodion plates, mainly positives. Shortly after, France and I established Scully & Osterman and we were exploring what we could do with the process. I was also teaching my high school students wet collodion and several other processes at this time. In early 1995 a representative from George Eastman House International Museum of Photography and Film in Rochester, New York, asked to come down and watch us make some images. Shortly thereafter we were asked to come to the museum to teach what turned out to be the first public workshop of the current collodion revival. We also wrote a complete basic manual for workshop participants, which is still a popular resource for people learning the process.

ROBERT | One of the things that people doing wet plate often do not know is that collodion based photography never really died, and thus nobody really brought the wet plate process back. Please tell us something about the history of the process, i.e., about its invention in 1851, and explain to our readers the difference between collodion negatives and ambrotypes and tintypes.

MARK | That’s true. The wet collodion process never really died. It was used up to the late 1960s in parts of the world for commercial photomechanical work. There have also always been pockets of people working with the collodion process in isolation for different reasons. So, the embers were still plenty warm when we came on the scene. France and I just fanned it to a more healthy flame. In 1995 we began publishing The Collodion Journal, a quarterly that gave us a platform for our research.

Several different people were involved in the development of collodion as a photographic binder, but Frederick Scott Archer is acknowledged as the “inventor” since he was the first to publish a complete working formula in 1851. His process was originally used for making negatives on glass, followed by stripping the thin collodion film and transferring that to a sheet of paper. The second step was abandoned by most photographers until it was revived for graphic arts use in the twentieth century.

Between the mid-1850s and 1900 many variants of the process were introduced, but the ones that have become the signature of the modern collodion movement have primarily been the ambrotype and tintype. These are both direct positive processes; meaning there is no intermediate negative needed. They are direct positive images on glass or black metal plates respectively.