psvensson
Member
Some of you may have seen my complaints about graininess in sulfite-free phenidone-ascorbic Gainer formulas on photo.net. I've experimented a bit further, and have managed to get fine grain without sulfite by keeping pH low. Using borax + boric acid works, for instance, as does TEA (though this is somewhat surprising, since I believe borax should have a lower pH all by itself than TEA).
The problem is that with low pH, shadow speed is also quite low, perhaps a stop or 2/3 below D-76 on Tri-X and Delta 400. Adding back some sulfite helps increase emulsion speed, but grain increases too, at least until I add so much sulfite that the solvent effect starts to kick in (at perhaps 50g/l) - and then I'm back where I started.
One thing I've noticed is that doubling the amount of phenidone, without increasing ascorbic acid, raises the shadows. This fits in with the description of phenidone as a developer that works quickly but doesn't acheive much contrast. However, the Delta 400 negs get a somewhat odd, mushy look. Haven't tried printing them yet. If I increase phenidone by less than double, the speed bonus decreases proportionately.
Anyone have any suggestions on dealing with the speed issue, apart from downrating the film?
The problem is that with low pH, shadow speed is also quite low, perhaps a stop or 2/3 below D-76 on Tri-X and Delta 400. Adding back some sulfite helps increase emulsion speed, but grain increases too, at least until I add so much sulfite that the solvent effect starts to kick in (at perhaps 50g/l) - and then I'm back where I started.
One thing I've noticed is that doubling the amount of phenidone, without increasing ascorbic acid, raises the shadows. This fits in with the description of phenidone as a developer that works quickly but doesn't acheive much contrast. However, the Delta 400 negs get a somewhat odd, mushy look. Haven't tried printing them yet. If I increase phenidone by less than double, the speed bonus decreases proportionately.
Anyone have any suggestions on dealing with the speed issue, apart from downrating the film?