Jumat, 17 Mei 2013

An evening with the Wet Collodion Process

Last night I attended an introductory demo of the wet collodion process at the Center for Alternative Photography in New York. Wet plate was the principle photographic process from the 1850's through the end of the 19th century. The process was used to sensitize metal plates to make tintypes, and glass plates to make ambrotypes.  The solution is very cumbersome to apply because the collodion, which is the carrier for the light sensitive silver nitrate, needed to maintain its wet state during the entire process, including the taking and developing of the image. For landscape photographers this meant having a darkroom tent with them when they were out in the field.

The Center for Alternative Photography in New York presents a variety of lectures, classes, and demos relating to older forms of photography.
The wet collodion process was used by most of the famous 19th century photographers, including Nadar, Mathew Brady, W.H. Jackson, Carleton Watkins, and Roger Fenton. It is still used today by artists and purists who love the process for the unique characteristics.

The demo was conducted by Eric Taubman, founder of the Center. After a brief intro, Eric took us through a step-by-step demo of the entire process from coating the plate to taking and processing the image.
Collodion looks like maple syrup and has a similar consistency. Once a plate is coated with the collodion it is dipped into a tray of silver nitrate, which then adheres to the collodion and makes the plate light sensitive. The plate must be then put in the camera, exposed, and processed all within about a three minute period so the collodion  does not harden.

Collodion is poured onto the plate and any excess is drained off leaving a thin, even coating. From this point on the photographer has about three minutes to complete the entire picture taking process including processing the image while still wet.
In the dark the wet plate is dipped into a solution of silver nitrate to sensitize it.

The camera and subject are set up ahead of time in preparation for taking the photograph.

As soon as the plate is sensitized it is transferred to the camera and the photographer guesses from experience what exposure time to use. The exposure is very slow so any portrait subjects had to hold very still.
Developer is poured over the exposed plate in the darkroom. Developing takes only about 15 seconds, after which the plate is immediately rinsed in water to arrest the process.

Rinsing the plate after development. Once the plate is rinsed it is no longer light sensitive.

For added permanence, the plate is run through a fixer bath.

The finished plate is then put out to dry and after a day or so is coated with varnish to make it permanent and protect it from scratches.
The wet collodion process is extremely fine grained, and with proper prep and processing also has exceptional resolution and permanence. Its sensitivity to the color spectrum gives it a unique look much coveted by artists who use the process today.

Bottles of prepared collodion and developer.

A 19th century book, The Silver Sunbeam, describes early photographic processes including wet collodion.
If you are in New York and interested in learning about early photographic processes, or want to know how to do them, I highly recommend the Center for Alternative Photography as a valuable resource. It is a non-profit organization dedicated to preserving all forms of early photography. Many of the courses are done in conjunction with ICP (the International Center of Photography) in New York, and encompass cyanotype, wet plate, calotype, salt paper, palladium, and many other interesting topics.

In addition to the courses, the Penumbra Tintype Portrait Studio is located on the same premises. You can arrange to drop by and for a very nominal fee ($75and up depending upon size) have your tintype portrait taken.

If you're really into early photographic processes, this place has a lot to offer.

Details:

Center for Alternative Photography
36 East 30th Street
New York, NY 10016
917-288-0343  

All photos in the post were taken available light with a Fuji X-Pro1 using either the f/1.4 35mm lens or 18-55mm zoom.  ISO was normally around 1600 except for the darkroom shots where I had to push it to 6400.

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