I’ve had some questions and interest lately in my collodion dry plate negatives. If you have my book, “Chemical Pictures - 2020” you’ll see on pages 136-139 the collodion dry plate process. I give the basic outline of what I use in the “modern” version of the process. I have modified Russell’s original process a little bit from reading Thomas Sutton and James Mudd over the last years. Just like all of these processes, you have to find your own way - practice, experiment, practice some more, experiment some more. You’ll get it.
“Mohawk Rocks” Early morning light on the mountain. I tried to frame it with the tree branches. I really like the limbs crawling into the top of the frame. This is very “soft” light and changes the quailty of the print a lot. It was a 10-minute exposure at f/8 - 90mm lens. Platinum Palladium print - Whole Plate. May 19, 2022
Major Russell first introduced the collodion dry plate process in 1861. I recommend you download and read his book, “The Tannin Process”, it’s free on Google Books. Moreover, I recommend you read the real jewel, “Collodion Processes, Wet & Dry” 1862 by Thomas Sutton. That’s where my practice is mostly based. Sutton has been a game-changer for me in photography.
Three collodion dry plates ready to load into the holders.
Tannic acid is a preservative. It allows you to keep the properties of the silver iodide and silver bromide “active” over a long period of time. Think of it as AgI and AgBr hibernation. The drawback is exposure time. I average between 5 minutes and 20 minutes. You can go a bit shorter or a lot longer depending on the aperture and the quality of light. There are plenty of other dry processes, too. The Coffee process, The Oxymel process (honey and acid), the Fothergill process, the Collodio- Albumen process by Taupenot, etc. The tannin process is the most popular because it’s easy to do and the preparation is simple.
The quality of the plate will depend on iodides and bromides in your collodion. Sutton talks about the perfect “opaqueness” of the plates. I can get them almost perfect for what I do. I rate them at ISO 1.
If you’re working in the wet plate process, or have worked in the wet plate process, you’re 95% of the way there. I would encourage everyone that wants the freedom to travel to areas where a mobile darkroom is not possible to explore these processes - especially the tannin process. Again, you don’t need anything special if you’re working in the wet plate process - tannic acid and maybe some pyrogallic acid if you don’t have it already. Simple.