Residual Developer in Negatives?

[Michael Veit]

I just developed 8 sheets of Tri-x in Rodinal 1/100 and found one had been ruine d 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 effect s 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-m easures.) My question is this: within seconds of immersing the negative, parts o f 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

[Doug Paramore]

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.

Regards,

[Pete Andrews]

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!)

[Ellis Vener]

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.

[Wayne]

I once took an emulsion off (accidentally) by leaving an 8x10 neg in a tray of water for a few weeks.

[Pete Watkins]

Bleach (household or otherwise) is most effective in cold water. Pete