Thursday, March 29, 2012

pH must be higher than 9,5

The last film I developed in Caffcol II (two baths developer), was very thin in density. The color was typical greenish, shifting the positive to magenta but after correction in software, all colors appear, I don't thing that is a problem.
But the second developer bath had a low pH and that didn't help CD-4 to work well. I also added sodium metabisulfite to CD-4 to preserve it from oxidation. And metabisulfite makes solutions more acid, so maybe I had less than 9,5 at the end and that caused the development not to be satisfactory. About the temperature, the experience I already made, showed me that all temperature above 26 ºC until 40 ºC will work with no significant changes in results.
Some of the past ones
Next time I expose and develop a color film I will use the strong coffee developer with sodium hydroxide. It gave good results at the end. And I hope to stablish the recipe for Caffcol II.

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