I've literally started reversal processing B&W this week, and my first results were not perfect (lack of contrast on FP4+) but certainly there was something usable (accidentally overexposed the film by 1/2 stop - maybe that's it?)!
I've done a lot of reading and seem to come across a couple of conflicting ideas regarding potential brown staining caused by a KMnO4 + H2SO4 bleach. Some methods suggest that this stain can be cleared using a Na2S2O5 solution (not sure if this is what's in the Foma clearing bath you use) but some methods suggest that Na-metabisulphite will NOT work, and instead one must use potassium metabisulphite.
Now, as I mentioned, I've started playing with B&W reversal this week and I used a KMnO4 + H2SO4 bleach with a NaS2O5 clearing bath and it worked fine... perhaps the staining issue is therefore dependent on the age of solutions?
I don't know if there's anything useful in my musings, but maybe it is worth checking/changing your clearing bath and see if that eliminates the problem? BTW - my method (at this early stage) is an almost direct implementation of that in Jens Osbahr's pdf (freely available online - and linked to on here), in which Rodinal is used as the 1st & 2nd Dev. - seemingly without any significant brown-tone issues. The only change I made was that I used Ilford multigrade as the 1st and 2nd dev. and like I said, slight lack of contrast (and possibly low D-max) - but worked with no staining.
Last edited by Jim Taylor; 05-22-2013 at 06:58 AM. Click to view previous post history.
Reason: correct bad spelling!!!