Monday, December 1, 2014

Caffenol Black LF (low fog)

Because Caffenol is a one shot developer, I use minimal amounts of stuff in order to make it cheap enough. I have been changing the coffee brand and the original recipe that uses only coffee and soda may produce more or less fog, depending on film and coffee brand. So, I started using Sodium Chloride (table salt) as anti-foggant. First only 2g/liter and then 4g/liter. Because salt is a restrainer, the developing time had to be increased from 70 to 90 minutes at 20ºC.

The formula, for a 500ml batch is now as follows:

150 ml water
10g Soluble, not decaf. robusta coffee
3 g Sodium Carbonate (or 300ml of a 1% solution)
2 g Sodium Chloride (or 20ml of a 10% solution)
Water to make 500 ml

Develop for 90 minutes at 20ºC

Here some photos I made recently using Agfaphoto APX 100 (may be like Ilford FP4), exposed in a Cosina plastic body with a Vivitar 50mm/1.7 lens. The iris of this lens are broken, it is always full openned and I used speeds from 1/500 to 1/2000s according to light conditions.





4 comments:

Minhaz Mahmood said...

Hello sir, I have Fujifilm 200 iso 35mm film. Will this solution work and should developing time be 90 mins? Thanks.

Henrique Sousa said...

Never used that film but I don't think the time will be very different. I would give it the same time, but it is up to you! You may also use a small portion of the tail of the film and make a test. Develop the portion for 75 min. and fix it and observe it against the light. If it lets too much light trough then increase the time. If not use it or decrease a little.

tcdp said...

In this case, didn't you use Ascorbic acid and in place of it it used common salt?? No Vit c at all??

Henrique Sousa said...

Coffee, alone, is a developer. Salt is used as anti-fog agent, like KBr. Vit. C is also a developer alone. But gives very weak negatives. Combined with coffe or Phenidone, gives excellent results.