Caffenol experiment

Those are attempts at developing film with Caffenol

First roll, Fomapan 100 from Flexaret (test) 2024-09-08

This is a roll of film that I knew was damaged by the camera (rollers for 35mm film dug into the emulsion and backing paper. I fixed it since)

Tried to develop it in Caffenol’s- main recipe

• Sodium Carbonate 54 g
• Vitamin C 16g
• Instant coffee (Belle France, store brand) 40g
• tap water to 1L

I think temperature was around 24 degrees, but I proceeded as if it was 20 degrees.

Dev for 15 minutes using ILFORD style agitation (1 minute, then 4 inversion per minute in a span of 10 seconds)

Results came out quite dense, with a lot of base fog.

Next time, control for temperature better.

May use this tool to convert the time. It seems the mixing of the soda is exothermic, and raise the water temperature by a few degrees.

As a reference, according to this online tool based on the ILFORD chart, 15 minutes of development should have been converted to 10 minutes

Second roll, fomapan 100 (2024-09-27)

Same recipe developed for 10-30 minutes, as the temperature was the same.

Same ILFORD agitation. Results were usable but still had fogging. Fogging was uneven. Unsure why.

I cannot easily source the right potassium salt (Kbr?). A friend mentioned to me that simple table salt sodium chloride could work as a anti-fogging agent. I have no idea. May try that next time.