Stop bath for printing - water or something else?

[lee]

as a silver printer I use citric acid as a stop bath helps make the smell of a darkroom a little bit better. however, for film processing I use water as a rinse btw dev and fix

lee\c

 

[sanking]

Acidification before an acid or neutral fix is said to reduce the potential for fixer stain and formation of dichroic fog in some fixers.

If you use an acid hardener fix, you can precipitate the alum out of the fixer onto your film or paper by going from developer to water to fix. The alum is difficult if not impossible to remove and can be seen as a white crust or sheen on negatives or prints. So, a stop bath is really a good idea with acid hardening fixes.

It has also been shown that uniformity in negatives and prints is somewhat better when a stop bath is used after the developer. The best example illustrating that is with the RA paper example above. Uniformity is best with a stop after development and before the blix. On large prints and LF or MF negatives, you can often see nonuniformities, streaks or mottle in large areas of uniform density.


PE

For several years I used a plain water stop bath with films but switched back to an acid stop bath after noticing the fixer stain or dichroic fog that PE mentions. This did not happen with all films but the fact that it happened once with some 10-15 sheets of 12X20 film convinced me that the water bath was just more trouble than it was worth. And since I switched back to the acid stop bath I have not had any more dichroic fog.

Sandy