Base recipe
All-purpose developer
| Water | 500 ml |
| Sodium carbonate | 20 g |
| Ascorbic acid (vitamin C) | 3 g |
| Aspirin | 3 g · about 3 sachets |
Adjust time to the film
First version (June 2016), starting point for tests.
Homemade chemistry · black & white · 2016 · Français
Homemade developer
recipes
The developers I created in 2016 and taught to my students in darkroom workshops. Everyday products — washing soda, vitamin C, coffee or aspirin — instead of industrial chemistry, in the spirit of caffenol. Shared freely: test them, adjust them, and tell me how it went.
Film developers
Tested on Ilford HP5+. Stand development: agitate at the start, then leave to stand. Seconds in brackets are agitation times.
HP5+ · box speed
Normal development
| Water | 500 ml |
| Sodium carbonate (washing soda) | 27 g |
| Vitamin C (ascorbic acid) | 8 g |
| Aspirin | 1 g |
30 min stand · agitation 15″ + 15″
HP5+ · push +1
Underexposed by 1 stop
| Water | 500 ml |
| Sodium carbonate (washing soda) | 27 g |
| Vitamin C (ascorbic acid) | 8 g |
| Aspirin | 1 g |
60 min stand · agitation 30″ + 30″
Same recipe as box speed.
HP5+ · push +2
Underexposed by 2 stops
| Water | 500 ml |
| Sodium carbonate (washing soda) | 27 g |
| Vitamin C (ascorbic acid) | 8 g |
| Aspirin | 1 g |
60 min stand · agitation 15″ + 15″ + 15″ + 15″
Same recipe as box speed.
HP5+ · pull −1
Overexposed by 1 stop
| Water | 500 ml |
| Sodium carbonate | 40 g |
| Vitamin C (ascorbic acid) | 12 g |
| Aspirin | 1.5 g |
15 min stand
Paper developer
B&W paper
Paper developer
| Water | 500 ml |
| Sodium carbonate | 20 g |
| Ascorbic acid (vitamin C) | 5 g |
| Aspirin | 2 g |
Develop by inspection until the blacks are deep
In the darkroom
- Mix — dissolve the powders one by one in warm water, in recipe order. Mix just before use: the developer oxidises quickly.
- Develop — pour into the tank (film) or tray (paper) and agitate as shown.
- Stop — rinse thoroughly with clean water.
- Fix — sodium thiosulfate fixer, following its instructions.
- Wash and dry — wash in running water, dry away from dust.
Safety. Sodium carbonate irritates skin and eyes: wear gloves and glasses in a ventilated room. Never reuse darkroom utensils for food. Used baths, especially silver-laden fixer, must not go down the sink: take them to a recycling centre.
Frequently asked questions
Can you develop black and white film with coffee or vitamin C?
Yes. Washing soda (sodium carbonate) makes the bath alkaline, while ascorbic acid (vitamin C) and compounds from coffee or aspirin act as developing agents. This is the idea behind "caffenol". The recipes below give the amounts and times I use.
Do these recipes work for photographic paper?
Yes, with a recipe richer in vitamin C (see the paper developer). Develop by inspection until the blacks are deep.
Do I need a special fixer?
No, a standard sodium thiosulfate fixer works. Used fixer contains silver: take it to a recycling centre.