I made a bath of 3% solution of CD-4 and some drops of lemon to prevent oxidation. This bath, lasting 5 minutes, the time may be exceeded without over-development, is made «at room temperature» . After that, and without rinsing, a 500 ml bath of Caffenol made of 7 g (1 tsp) Sodium Carbonate, aka washing soda, and 14 g soluble coffee (4 tsp) lasting 10 minutes at 38 ºC. Maybe this bath can be shortened. After this, I fixed the film to see how it was. Very black silver. Then I bleached and fixed again to complete the process. And that is all. The Bleach was like previous made of Potassium Dichromate and Sulfuric Acid and the Fixer is the common one, Ammonium Thiosulfate.
And here are the photos
Actualization
Resuming, the normal procedure should be:
Bath | Duration /min. | Temperature / ºC | Obs. |
CD-4 | 5 | R.T. | First minute agitation |
Caffenol | 10 | 38 | First minute agitation |
Rinse | 1 | Warm from tap | 3 times fill |
Bleach | 2 | 30-38 | Continuos agitation |
Rinse | 1 | Warm from tap | 3 times fill |
Fixer | 5 | 20-30 | First minute agitation |
Washing | 30 | R.T. | 3 times fill and then take from tank and leave in water |
Dry | 90 min. | R.T. |
Formulary:
Developer (H. Sousa, 2012):
Bath A - 3% solution of CD-4 (CAS n.º 25646-77-9) with some drops of lemon juice to prevent oxidation
Bath B - 7 g soda + 14 g soluble coffee + water to make 500 ml
Bleach (Franz Dietrich ,1988)
9,5 g Potassium Dichromate, CAS number 7778-50-912 ml Sulfuric Acid ConcentrateDiluted 1:3
Water to make 1000 ml
Fixer (universal formula)
160ml Ammonium Thiosulfate 60%, CAS number 7783-18-8Water to make 1000 ml
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