There are many formulas for caffenol, all based on preparations that contain caffeic acid (i.e., coffee or tea) and a pH modifier, most often sodium carbonate. The chemistry of caffenol developers is based on the action of the reducing agent caffeic acid, which is chemically unrelated to caffeine.
The 1995 technical photographic chemistry class at Rochester Institute of Technology, led by Scott Williams, developed a method of developing photographic film using standard household items. They tested mixtures of tea and coffee combined with agents to balance the pH and successfully made printable images for exposed film.
- Williams, Scott. "A Use for that Last Cup of Coffee: Film and Paper Development". Rochester Institute of Technology.
- Film Photography Project: Coffee Break – Develop Film at Home with Caffenol, Film Photography Project.
- "Digitaltruth Photo: Caffenol Formulas". Archived from the original on March 22, 2016. Retrieved December 10, 2011.
- Moschetti, Vincent (March 15, 2017). "How to Develop Film with Beer". PetaPixel.
- "Wineol – Red Wine developer". June 20, 2012.
- Keating, Daniel (August 18, 2020). "Polyphenol Developer Alternatives – A World full of Options". 35MMC.