Residual developer in negatives?greenspun.com : LUSENET : Large format photography : One Thread
I just developed 8 sheets of Tri-x in Rodinal 1/100 and found one had been ruined by a hair which somehow got stuck to it in the process. Since the negative was trash anyway, I decided to experiment and stuck it into hot water to see effects of reticulation, whether I could melt the emulsion, etc... I was just fooling around. The first water bath was very hot, I didn't measure the temp, but we're talking hot enough to be uncomfortable to the touch (I don't do things by half-measures.) My question is this: within seconds of immersing the negative, parts of it darkened considerably, is it possible that there was residual developer in the thing which was activated by the temperature? I must say this was a surprise and has me a bit confused and worried.
-- Michael Veit (firstname.lastname@example.org), February 19, 2002
Michael: Maybe you scorched it. Seriously, it is an interesting effect. I do know that hot water will remove the emulsion. I once had a trainee wash six rolls of 120 film in hot water and left a clear film base. He turned the water on and left, not realizing he had turned on the hot water. Let us know if you do more experimenting and get the darkening effect.
-- Doug Paramore (Dougmary@alaweb.com), February 19, 2002.
I've dissolved the emulsion off scrap glass plates many times, just to get a piece of thin glass, and I've never seen an effect like you describe.
Maybe the film wasn't fixed properly.
BTW, the way to remove the emulsion efficiently is to use a caustic solution. A warm 5% sodium or potassium hydroxide bath takes the emulsion off much quicker than hot water alone. (Use rubber gloves and don't get it on your skin or clothes. It eats through cotton quite quickly too!)
-- Pete Andrews (email@example.com), February 19, 2002.
simple household chlorine based bleach will also take all of the emulsion off of film. Make sure there is a lot of ventilation and use gloves.
-- Ellis Vener Photography (firstname.lastname@example.org), February 19, 2002.
Anyone know if one of the emulsion removing concoctions will allow you to take it off like a polaroid transfer?
-- Dan Smith (email@example.com), February 19, 2002.
I once took an emulsion off (accidentally) by leaving an 8x10 neg in a tray of water for a few weeks.
-- Wayne (firstname.lastname@example.org), February 20, 2002.
Bleach (household or otherwise) is most effective in cold water. Pete
-- Pete Watkins (email@example.com), February 20, 2002.