Quote Originally Posted by gainer
Interesting. Did you notice tanning as well as staining? I think amidol is listed among the moderately tanning agents. I'm don't know what other ingredients you added, but would assume sulfite to be among them.
Color is sometimes dependent on grain thorugh diffraction as well as staining. Could that be a factor?
Hi Pat,
The basic formulation is Michael Smith's Azo contact paper developer formulation, so: 30 grams/liter sodium sulfite, 3 grams/liter citric acid, 2ml 10% KBr/liter. The Azo recipe calls for 8 grams/liter Amidol. I just poured in a small dollop (maybe 3 ml) of my ~ 4% Amidol/PG stock solution. The rest of the chemistry is faithful to the proportions in Michael Smith's formulation.

Since the test pieces of film are uniformly exposed to diffused light (thus no coherent image) it is difficult to judge if tanning or proportional staining is taking place. There is definitely blackened silver plus a dark olive green stain. I'll take a look with a microscope and see what else I can see.

BTW I developed a second test piece of film this evening when the solution was 8 hours old and saw no difference in activity. I fixed this piece in home brew Kodak F - 24 non-hardening fixer. The stain was very uniform this time.

I am tempted to try a roll of Efke 100 with real images. That should make it much easier to determine if tanning and/or proportional staining is happening.

Hey! Did I just step out onto a slippery slope?