Are you intrigued by the title?
Wonder no more. This is a post about the use of coffee to process black and white film.
Known as Caffinol, this system of processing black and white film was brought to my attention by a former work colleague of mine, so I decided to give it a try.
The process is useful if you don’t like the idea of using traditional black and white film developers, are intolerant to metol (a common component in some developers) or even have run out of film developer and need to urgently process a film.
At this point I have to assume you have processed negatives before now. The technique is actually no different to conventional processing so no need to panic!
The formula
This particular version is known as ‘Delta Formula’.
12 Level teaspoons of washing soda – powder not crystals
3 teaspoons of vitamin C powder
18 teaspoons of coffee powder – not decaffeinated.
1 litre of warm water
Dissolve the washing soda in 750ml of water, the coffee in the remaining water, adding the vitamin C to the coffee solution and finally mix everything together. Leave the solution to stand for at least 5 minutes for any bubbles to disperse.
Develop the film for between 10 and 11 minutes, agitate continually for the first 30 seconds, then agitate for 5 seconds every minute for the remaining time. Rinse the film several times or use stop bath, fix the film using conventional fixer for the recommended time and finally wash the film as usual.
For the purposes of this review I used Ilford Pan 100 rated at box speed using a Nikon F90x with a Mir 35mm f2 manual focus lens.
The results
Full frame – cropped area shown below
Cropped area
Conclusions
This method of processing black and white film is best suited to slow to medium speed films since it is not a fine grain developer. Contrast however is good as sharpness.
I have used coffee developer (or caffinol) as it is more commonly known to process films from 35mm to 5×4 sheet film all with equally good results.
Note that ‘cheap and cheerful’ coffee powder works best, no need to spend a small fortune on a well known brand.
This formula used is by no means the only one, a search on the web will provide a whole gamut of variations of this formula all producing slightly different results, just take your pick.
Colin