Wet-plate collodion photography has been around since Frederick Scott Archer introduced it to the world in 1851. Collodion was used to produce glass negatives as well as ambrotypes and tintypes. It usurped the Daguerreotype in its ease and versatility, and has aesthetic merit today.
When slightly over-exposed and over-developed, a beautiful negative is created that can be used to produce multiple prints of the same image. When under-exposed and under-developed, a beautiful thin negative is produced on glass that, when backed with black, appears as a positive. When exposed onto a piece of metal (not really tin, but a blackened piece of aluminum), the image also appears as a positive and is not as fragile as glass. One downside: Because each image has to be made while the glass is still wet, photographers have to carry everything required with them when in the field.
There has been a resurgence in the use of collodion over the last several years by contemporary artists, many of whom are combining techniques that span the three centuries of photographic tools. The hands-on quality of this process is uniquely expressive and intriguing to both artist and viewer.
There is a learning curve to this process, but that, too, is fun. The emulsion is not sensitive to many colors: red, orange, yellow, brown, green, or blue. So the first thing you might want to do is take a photograph of objects with different colors as well as shoot them with a digital camera to test how they will appear in this medium. It’s like making your own color wheel. The faded tonalities, blurs, and flaws in each image make them truly unique and reminiscent of the past.
The process of wet-plate collodion photography entails taking a piece of glass (or with tintypes, aluminum), cutting it to size, cleaning it, and then “pouring the plate.” That means pouring the collodion mixture on the glass, then placing it in a silver bath. Once this is done, the plate is put into a plate holder (similar to a film holder) and exposed. After exposure, the plate needs to be developed immediately (hence the name “wet plate”). Once the image dries, it is varnished for permanence.
Students take workshops and leave thinking they cannot possibly do collodions on their own because of all the equipment required. A lot is needed, but there are ways to get around some of it, so read on.
Before you go out and get everything, you need to be mindful about your ventilation. You should not do this process at home if you don’t have a safe place to work. You not only need good ventilation, but you also need to have safety glasses, gloves, apron, and glass containers.
You cannot just go out and buy the chemicals anywhere. You have to order them from specific supply houses, and they must be delivered to a building— not a post box. I have included a list of sources at the end of this article that is pretty good, but not all-inclusive by any means. I use glass beakers, bottles, stirrers, and funnels. You can get them online or at some stores that sell scientific supplies. I also have a mixer—it works with a magnet and mixes the chemicals for you. Mixers have gotten very expensive, but look on eBay.
More things that you need
When making collodion negatives, you need to be near your darkroom— remember this is the wet-plate process. The glass needs to stay wet through coating and sensitizing, as well as shooting and developing.
You also need a glass-plate holder. Glass is thicker than film, so you need to either make one out of an old film holder or have one made for your camera. You also can use old Brownie cameras and make images the size of that particular camera. Other than that, you are ready to go.
I clean my glass with Bon Ami. It is a nonabrasive cleanser that is cheap and easy to get at most grocery stores. Pour some on the glass and use a cloth or paper towels and hot running water. Make sure the water runs down the glass in a sheet, like a waterfall. If you see uneven areas, then wash it again.
Once the glass is washed, set it on a drying rack until you are ready to coat with emulsion.
Pouring the plate
With white lights on, hold the glass in your left hand (if you are right- handed) by the lower left corner or underneath using your finger tips for balance. Pour the collodion in the center of the plate and gently tilt first to the lower left corner, then the upper left corner, then the upper right corner, and when you get to the lower right corner, tilt the plate and let the excess collodion run back into the bottle. Rock the plate from side to side to prevent lines from forming.
Now, turn the white lights off and under a red or amber safe light, and using protective gloves, lower the plate into the silver solution. This is called sensitizing the plate. Do this in one swoop or you will get a line where you hesitated. If you are using a tray, make sure the plate is collodion-side up. The plate is ready after about 3 minutes. When you take the plate out of the silver, you should not see any lines or beading up—it should look smooth (like the clean glass did under the water).
Place the plate in the plate holder under an enlarger or directly into a box camera and expose your image. Start off assuming the plate is ISO 1. Because collodion is not sensitive to red wavelengths, the exposures are trial-and-error. After awhile you will get used to it and can figure it out as you go along.
There are several ways you can develop your plate. • Tray developing. While this is not the best way to develop, it is the easiest.
• A helper tray. This is a piece of Plexiglas with a hole in the bottom and all sides built up. It helps keep the developer on top of the plate.
• In your hand. This is the most “professional” way to develop, but by far the hardest. It takes practice to hold the plate steady enough that the developer does not fall off the edges but still moves the on top of the plate.
You want just enough developer to cover the plate. The less developer used, the stronger the image. You want to stop developing before you see your deepest shadows. This step should take about 15 seconds. If it takes longer than about 20 seconds, then you have probably underexposed your image. If you see the image come up before about 10 seconds, then you probably overexposed your image.
Rinse your plate under cool running water until the greasy look is gone from the top of the plate. You should wash the front and back of the plate.
You can now turn on the white lights.
Fix and wash
Sodium thiosulfate fix: Fix for about 5 minutes. Wash for about 10 minutes in running water.
Cyanide fix: You should not fix in cyanide for more than 3 to 4 minutes. As soon as you see the image clear, time it for 2 minutes, then remove immediately or the cyanide will bleach the image (be sure to wear protective gloves). Wash for about 10 minutes in running water.
Your image will lighten as it dries.
1. Heat the varnish by placing it into a beaker of hot water for a few minutes.
2. Heat the back of your plate over a lamp until it is warm, but not too hot to touch. I use an oil lamp with clear, smoke-free oil.
3. You want both the varnish and the plate to be around the same temperature so that the varnish flows evenly over the plate.
4. Pour the varnish on the plate the same way you poured the collodion. However, you can go slower, and unlike pouring collodion, you can go back and forth.
5. Drain the varnish back into a used- varnish bottle, not the clean-varnish bottle. This varnish has to be filtered before it can go back into the clean bottle.
6. Set the plate vertically and let it drain onto newspaper or a paper towel. Then set it on a rack to dry. When it has, store the plate in an archival envelope.
Now it’s time to decide how you want to display your images. As you can see from the collodion portraits reproduced here, the wet-collodion process may not be simple, but it creates images no other photographic process produces.