Gelatin Ambrotype/Tintype Developer

5 grams Ferrous Sulphate
(dissolve in acidified water, a dropper of vinegar)
20 grams Sodium Citrate
top off with to 70ml
Add 1 dropper of 10% K Bromide.
(Add a dropper of Silver Nitrate before first use.)

Develop for 10 – 30 minutes. Keep and reuse.

This is a modified formula of the Eastman formula in Ernst Lietze’s Modern Heliographic Formula. It lessens the overdevelopment risk of the paper developer/exhausted fixer combinations, and helps with frilling problems.