Archived posting to the Leica Users Group, 2005/11/23
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]> I've been up and down and in and out on stop baths. Back and forth. > I stopped because it seem for awhile that all the real hard core darkroom > people had stopped using it for all these various reasons. Pinholes. The > shock of the acid making more grain. Or grain clumping. I think there is something to that... Any time you can keep the chemical or physical conditions (pH, ionic strength, temperature) as constant as possible, the image benefits. On and on. > They only thing I figured out different was my fixer (HYPO) lasts a heck of > a longer time when I use stop bath. Really conks out faster when I don't. I use Ryuji Suzuki's neutral rapid fixer which is NH4 thiosulfate in sulfite/metabisulfite solution (pH 7.0-7.1). I have never had the fixer itself conk out (ability to clear film in less than 40 seconds) but the sulfite/metabisulfite oxidizes to sulfate rapidly (carried over developer has nothing to do with this) and it won't facilitate the removal of the @#$%^ antihalation dye from 35mm film as efeciently as fresh. Tri-X and TMX/TMY are the worst and need fresh sulfite and lots of washing to decolorize. I usually make fresh fixer every two sessions anyway, or use a sulfite/metabisulfite wash aid. > This is part of general information I'm surprised no one said that yet. > Everything but! > I never got a pin hole in my life. > And that a thing I would never lie about. You will probably not get pinholes if you don't use sodium carbonate accellerated developers. They produce CO2 gas when combined with acid, sometimes, such as acetic acid stop or fixer. Borate buffered developers don't do this. Old time D76, I think, used to have sodium carbonate in it but has been reformulated to use borax/boric acid or metaborate I think. No gas. Take Tums and you won't get pinholes! JB