Caffenol – September 2023

Ilford HP5 35mm film shot on Pentax K1000. Black and white negs scanned in colour, as I do love the tones on caffenol negs. Recipe still not quite decided as variables in experiments keep changing. In essence, caffenol uses a home made film developer in place of the chemical developers usually used. Its made from instant coffee, washing soda, vitamin C powder, salt and water. I acknowledge that coffee is not an entirely sustainable and ethical substitute but am interested in it’s use as a less chemical solution to end up in drains, waterways or gardens. My hope is that by taking the time to understand the chemical processes of caffenol development I can adapt that understanding gradually to other local materials with similar abilities, or waste coffee grains. Litmus paper has been purchased for further diy recipe tests.

Tests to date have used a wide variety of cameras, as analogue mediums have a tendency sometimes to give up or go nuts. This is my second roll from my new Pentax K1000 gifted by an uncle who no longer used it. On this roll, the camera rightly decided it needs a full service and clean, with light leeks from the right and sticking mirrors. The photo’s are still coming out nice even if the control of these experiments may not be as easily documented.

With the last batch of HP5 I developed I found the images just a little flat so I left the film to develop a minute longer. I had been using about 13 minutes up till now. Film is developed as normal with caffenol solution. Pour into tank, agitate for 1 minute and then again for 10 seconds every minute. I stop bath using water with vinegar added for 1 minute. Im still using a chemical based fixer, Ilford Rapid Fix, but I reuse this for quite some time. Fix for 6 minutes and then wash in clean water for 15 minutes (running water forced through for a few minutes then reduced to a trickle to conserve water.)