I've been away from DA for almost 9 months and during that time many things happened, good and less good. So let me tell you about the good things, or better, the best thing, which is my start with the wetplate collodion process, a process I fell in love with the first time I saw some plates at a demonstration some years ago.
As for the process, Frederick Scott Archer described 1851 an application of salted collodion on sheets of glass for the purpose of making glass plate negatives. He detailed a process where potassium iodide was combined with a solution of diluted Collodion (diluted with alcohol and ether), applied to a glass plate, which was then immersed in a silver nitrate bath resulting in a light-sensitive layer of silver iodide.
Well, that sounds pretty simple, which actually is. The important part in this process is the security. You need to get familiar with the chemical hazards associated with this process, as most of the used chemicals are flamable or explosive, as well as poisonous. You need to burn this in your brain. Improper use can cost your life!
I had the good luck and honor to catch the knowledge and "hand moves" from one of the most appreciated "Collodionist" in Europe, Quinn Jacobson. In August 2009 I was finally infected by the collodion process virus
In the next lines I will try to describe the "birth" of such an image, so you get a clue what happens behind the scenes.
First of all you will need a camera that is able to hold a substrate (glass plate, aluminum plate).
View cameras with modified film holder can be used as well as wetplate cameras that you can order from designated manufacturers. In order to stay timely with the process, 1850 and later, most collodion afficionados use camera designs and lenses from that period.
Below you can see my camera, an 8x10 Anthony Style Bellows camera, built by Ray Morgenweck of Starcamera Company, NJ. Is a cherry wood replica, built after original plans.
The lens is a french Derogy No.4, an original from 1869 (according to the serial number and VadeMecum).
Ok, so let's move to the next steps.
this is the glass plate that will cary the image scrupulous cleanliness is required. cleaning the substrates avoids that the collodion will peel off and your image is free of spots.
pouring the salted collodion. this is the layer where the image will be created.
silver nitrate bath. it makes the collodion layer light sensitive.
after 3 minutes in silver nitrate bath the plate is ready. wipe off the excessive silver nitrate from the rear side of the plate. it keeps your plate holder clean... and your hands too (black hands)
place the plate into the film holder and you're ready to shoot
after exposure, the plate is taken out and developed using a ferrous sulfate developer
at the end of developing, rinse with water
and then fix
The final image can be now varnished and is ready for framing. Clear glass negatives can be used for further process, such as albumen or salt prints after intensifying, or create contact prints on traditional silver gelatine paper.
If you wonder about "slow photography", here's the reason why. Unless you have an assistant that is cleaning, pouring, sensitizing and developing plates for you, you need to expose each plate right after the plate is in holder and still wet, hence the name "wetplate". All that takes its time, usually 15 mins per plate.
Another point for "slow photography" is the fact that the used collodion has an ISO value less than 1 (yes, ONE) and the most common exposure time is ~5 seconds depending of the light quality and the amount of UV light. 5 to 10 seconds are ok for portraits, most people can deal with it. For still lifes and landscapes it doesn't matter.
Thanks for your time, I hope you have enjoyed the reading.