A great percentage of Lab-Box backers opted for Caffenol as a developer. Caffenol is a very "simple" developer for B/W film that easily forgives exposure problems, and it’s also easy to use. Believe it or not, you can easily develop your B/W film by yourself with coffee. Ars-Imago’s kit contains all the ingredients you need and a little guide. But to get good results requires that your images have been properly exposed before.
But, unfortunately, you can’t drink it.
Caffenol is an alternative photographic development process based on instant coffee, washing soda, and ascorbic acid – aka vitamin C. There are several recipes for Caffenol, the most famous being Caffenol CM and Caffenol Delta. Among the variations, Caffenol CH is fit for higher speed films; employing the addition of potassium bromide , Caffenol CH suits higher sensitivity films best. ars-imago’s recipe for Caffenol is a variation on (o takes after) Caffenol CM.
Allegedly, the first to experiment with Caffenol were the Technical Photographic Chemistry class at RIT (Rochester Institute of Technology), in New Jersey, USA, in 1995 led by Dr. Scott Williams, who managed to develop 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.
However, mixtures of coffee and other alternative developing techniques were also used during the second World War. It was a quick alternative to chemicals for photographers reporting from war fronts. Evidence for this can be found in Hans Windisch’s The Manual of Modern Photography. Windisch was a german photographer and a university professor both before and after WW2. In his book, he mentions sources of replacement chemicals that were necessary in Germany during WW2, and is not unlike the situation home-developers find themselves in today. He was also the originator of several famous german fine-grain developer recipes that he discusses thoroughly in his book.
Website with great infographics:
Film development charts:
Videos and tutorials: