View Full Version : Why daylight doesn't harm developed wet-plates, but does harm film.

Sylvester Graham
16-Oct-2012, 16:44
My question is simple: Why is it that we can develop collodion wet plates and then bring them out into the daylight to fix, but can't do the same for film? Don't both processes use silver halides as a photosensitive material?

I am bringing the question here because there has been a range of responses to my thread on collodion.com and I would love the input of some of the experts here on LFforums.

Thank you

16-Oct-2012, 22:06
You can bring developed film out into light - see the BTZS instructions that say you can uncap a tube to dump the developer and put it in fixer while in room-light. Developing film reduces its sensitivity dramatically, though I couldn't tell you the chemistry of how.