BROWN COATING ON FILM

[Tomas Polensky]

I processed 30m of FOMPAN 100 R film in MORSE G-3 tank. I used standart FOMA Reversal KIt. Everything was fresh and unused before. I even doubled the time of each step. The result is brown non-transparent coating which cover the whole film strip. There is a visible image but the brown coating disables to see through. I tried to put it back in clearing bath but it didn't work. So I mixed 2g of KMnO4 with 1 l of water. The brown coating dissolves in KMnO4 but it turn out to be negative even though the visible image on damaged film is positive. Do you have any experience with it? Any suggestions?

Thank you

[Simon Wyss]

Make sure you have enough agitation in the clearing bath. That is as important a step with reversing as are all others but often neglected. A little additional alkali might help in the desired direction.

 

No harm from a short water bath after the bleach.

 

Next, second exposure must be thorough and with incandescent light only. Give the whole film two minutes under a frosted 60 W bulb at 18 inches distance, no less, in motion, under water (the film, not the bulb).

[Tomas Polensky]

Make sure you have enough agitation in the clearing bath. That is as important a step with reversing as are all others but often neglected. A little additional alkali might help in the desired direction.

 

No harm from a short water bath after the bleach.

 

Next, second exposure must be thorough and with incandescent light only. Give the whole film two minutes under a frosted 60 W bulb at 18 inches distance, no less, in motion, under water (the film, not the bulb).

 

I really don't know what what I did wrong. I know that motion is very important and that's what I did. Acording to the morse g-3 manual I winded the whole reel for less than 1 min a than again repeating till the end of each step. I rinsed the film with running water after each step. For second exposure I used exactly what you've written but I gained brown coating on the whole film strip. I seems to be between base and silver image. This wasn't my first time processing. I did exactly what I've been doing every time. i just don't understand what could cause it. Any idea? It's just a mystery to me.

[Simon Wyss]

Well, now, it looks like something is wrong with the bleach step. What acid do you have in there?

Edited August 15, 2012 by Simon Wyss

[Brian Pritchard]

It sounds to me as if the anti-halation undercoat has not been bleached away before the second developer. This is made from colloidal silver and is designed to be bleached away when you bleach the negative image. Unfortunately if this is the problem you cannot remove it without losing the image. This anti-halation coating prevents you using the film stock as a negative.

 

Brian

[Richard Tuohy]

I agree with Simon's suggestion: did you perhaps forget to add the acid to the bleach?

[Richard Tuohy]

Another thought: you say you doubled the times, but what times did you double? The times specified by Foma for tank processing ... or do they also specify times for rewind processing? Rewind processing takes a lot longer.

[Simon Wyss]

Yes, very good, this must be it. I am not familiar with the Morse apparel but there’s the rub.