Wet plate collodion is a very old process that dates back to 1851 and is the process that followed the daguerreotype. Its inventor is usually considered to be Frederick Scott Archer but it appears that Gustave Le Gray came to the same conclusions simultaneously.
Photography evolved quickly from then on moving on to dry plate collodion and modern emulsions.
A small group of people continued to use (or resuscitate) the process. There seems to be an increasing interest in slow photography, creating single images and the look that is so specific to wet plate. Maybe it’s just wanting to return to a way of working for which you take the time, that cannot be fixed in post-processing. Whatever the reason you have to enjoy a challenge and I don’t think any of us continue to do this without loving it completely.
The steps of the process
1) Preparation of the substrate: usually a glass plate (ambrotype) or black anodised aluminium (tintype)
2) Pouring the plate: collodion, a syrupy yellow liquid, is poured onto the plate. This is the base of the emulsion.
3) The plate is dipped into a solution of silver nitrate for a few minutes to make it photo-sensitive. The silver allows the image to print itself onto the emulsion.
4) The plate is put into the holder and exposed in the camera.
5) The plate is developed.
6) Then it is rinsed abundantly to stop is developing too far.
7) Then it is put into a fixing bath turning the negative into a direct positive.
8) The plate is set on a rack to dry.
9) It must then be varnished and/or waxed to protect the image from oxidisation, humidity and oils left behind after touching it.
A well-made plate that was preserved adequately should still be intact 150 years from now. The process is slow and complex. The emulsion must stay wet through most of the steps. If it dries it loses its sensitivity.
Due to the nature of this technique each image you make is unique, impossible to reproduce. There is no noise or grain like you would find in later processes. The detail you can achieve is incredible. You end up having an object in your hands, you made a picture, you didn’t just take it.
Yes, you can scan a plate, most of us do but you lose some of it along the way. The result just isn’t the same.
Wet plate holds some element of “mystery”, the balance between the chemicals is fragile, it doesn’t take much for it to subtly shift into something with very different results creating artefacts, edges, faster of slower collodion, and so on.
It is this part of uncertainty that probably keeps us interested. You do not have much of a chance to get bored and the learning curve is steep and long. Some days it works beautifully, others it won’t for not noticeable reason which is when the detective work becomes necessary.
Exposure times tend to be longer than for more modern mediums. Back in the day you did not smile when you sat for a portrait. It is impossible to keep a natural looking smile for 10 seconds without it turning into a grimace. Today modern (and old) technology can help dramatically reduce exposure times. We are so much more accepting of out of focus images. A wet plate portrait can really show you something special, the blurriness can be more expressive and the longer exposure times allow us to go wherever we go in our minds when we are not being watched. The photographer fusses over equipment leaving the sitter to feel. Some portraits or entire sessions can be deeply moving.
Colours also need to be ‘translated’ into wet plate. The emulsion reacts strongly to the blue spectrum of light. Because of this, blues become lighter (blue eyes can become white, blue make-up disappears), tattoos can disappear altogether, reds and yellows become black. If you have freckles they will be more visible.