Caffenol (C-M)
A developer made from coffee, soda, and vitamin C — no store chemistry.
About this developer
Caffenol works because polyphenols in instant coffee develop film much like a conventional developer — washing soda makes the solution alkaline, and vitamin C boosts and speeds up the reaction. Use it immediately after mixing: it oxidizes and loses activity fast.
Mixing & using it
- 1Dissolve the coffee in part of the water.
- 2Separately dissolve the washing soda in another part of the water.
- 3Combine the coffee and soda solutions, then add the vitamin C last.
- 4Pour into the tank immediately and develop at 20°C.
- 5Agitation: continuous for the first 30 sec, then 3 inversions per minute.
- 6Pour out, rinse the film several times, fix, and do a final wash.
Development time
| Film | ISO | Time @ 20°C |
|---|---|---|
| Fomapan / Neopan 100 | ISO 100 | 15 min |
| Ilford Delta 400 (with salt) | ISO 400 | 15–20 min |
For films above ISO 100, add a pinch of salt — it suppresses the fog coffee causes at higher sensitivities.
Recipe for 1 liter
1 L
Water
54 g
Washing soda
16 g
Vitamin C
40 g
Instant coffee
Mix in this order: coffee → soda → vitamin C last. Dissolve the soda in a separate container to avoid a sharp temperature spike when it meets the vitamin C.