I recently tried caffenol development for the first time. I was developing TriX shot at 1600, which I couldn't find a developing time for. I went with a two hour stand development and noticed that the entire negative strip came out completely black and opaque. Is this due to overdevelopment? I also didn't use instant coffee but brewed coffee that was still slightly above room temp.
There could be 1001 reasons why your negative turned out the way it did. But assuming:
- you had used a proven recipe (google Caffenol Cookbook) and
- you have done your development properly (too many tutorials on this if you care to google),
then my best guess would be that somehow your negative had been exposed to light prior to development. Evidence to support this includes:
- it is completely black and opaque, not even the DX barcodes on the edge of the film can be seen
- the nature of caffenol being a compensating developer. It is highly unlikely for a roll of film be completely opaque (due to overdevelopment) even after 2 hours of soaking. Caffenol-C-L is one recipe suitable for stand development for 1-2 hours.
If my assumptions above were wrong, then I would say there was no development at all.