Quote Originally Posted by Jerevan View Post
I know that this is really out on the fringe of emulsion making, but why does one use collodion for wet plates? What better (or different) properties does it have compared to gelatin or gum arabic?
Great question, Jerevan!

I seem to remember a story that Dr Maddox, who's credited with discovering gelatin as an emulsion base, was motivated by the smell of ether. He hated it! I've heard of worse motivations for discovery.

Gelatin dry plates were seen as a real breakthrough in photographic technology. Mostly, at first, it was about convenience. You could make the plates ahead of time, take them into the field and bring them back weeks or months later for processing. I can't even imagine how nice it must have seemed not to have to haul your darkroom every place you went. And, even with your darkroom (wagon or tent) at your elbow, in hot, dry conditions it could still be a challenge to get a plate poured and exposed and developed before the collodion dried and became unusable.

After gelatin came along, it was discovered that silver bromide could be used instead of the silver iodide in the collodion process (And my history goes way soft here. Someone who does wet plate could tell more about the details.) Using gelatin let the silver bromide, which is inherently much more sensitive than silver iodide, be 'ripened' at high temperatures for a long enough period of time that it got even more sensitive, i.e. 'faster' speed. Convenience, combined with better speed, pretty much revolutionized photography, almost literally overnight, especially when commercial manufacturing took over and photographers could buy their materials instead of having to make them on the spot. Of course, that exact artisan characteristic is most of the appeal of wet plate collodion today.

Motto: Never second guess the future, at least as far as historians and artists are concerned!