I wanted to try a coffee-free caffenol to reduce a) the smell and b) the cost. The general consensus seems to be that instant coffee contains around 3 % caffeine, so I replaced the 40 g of instant coffee with 1.2 g caffeine, and used the rest of the formula for Caffenol C-H just as is. The film I used was Kentmere 400 (because I wanted to test with an inexpensive film first). I settled on 15 min development because that is typically what I use for Caffenol C-H, and got completely underdeveloped negatives:confused:. I would say the N+3 to N+4 looks about normal density. Over and above that, the film was fogged significantly. So I tried increasing the caffeine content to 3 g, and added 1 g KBr to prevent the fogging, keeping the rest the same. This only made things significantly worse, by about another two stops. N+5 looks like something can be rescued from it, but it is still under by a stop at least. Okay, so what now? I can only infer that the super-additive component in instant coffee isn't the caffeine, but something else. Or my pure caffeine somehow differs from the form in coffee, but I have never come across any reference to that being a possibility. The ascorbate I use is the same that gives totally acceptable results with instant coffee. Can anyone else make sense of this? I desire a non-staining caffenol-type developer for paper, too, purely for environmental reasons, and was hoping this would work, but it seems it's back to phenidone for now.