Caffenol

So I did something odd this weekend: I successfully developed film using £8.65 of stuff I bought at Morrisons in a panic.

In true recipe-blog style, the backstory: I got a new lens as an impulse purchase (20mm f/2.8 AF-D, it’s lovely, never used anything that wide before), and since I was off out for a walk thought I’d shoot a roll of film to try it out with. Got home, set up to develop it, found there was no developer. Wait! There was a new bottle of developer.

Neither Iona nor I could open it. We tried for ten minutes before admitting defeat.

But, wait once more! Caffenol! Which I had vaguely wanted to try one day. Rapid googling confirmed, yes, it was achievable. Clock said 22.40. Sprint to Morrisons, and find everything (including their one single bag of washing soda) just before they closed up.

First attempt a bust, but I went out the next day with a replacement film, and after a more careful reading of the instructions, these emerged on Sunday evening:

HOLLOWAY Police horses Dennis Queuing Lunch stall

In terms of the actual process, I used the Caffenol C-M recipe from DigitalTruth with a bit of crosschecking against the Caffenol blog on the complicated issue of what on earth actually constitutes “washing soda”.

The eventual mix I used (for my own reference as much as anything else):

  • 500ml water (only making enough for one film) at ~20C
  • Add 73g “washing soda” – the recipe calls for 27g but the stuff I got is actually “Sodium Carbonate Decahydrate”, which means about 63% by mass is water. Stir thoroughly until it is all dissolved
  • Add 8g vitamin C – I could not *find* pure vitamin C so I bought the highest value supplement I could find, 1000mg effervescent tablets. Made a surprising amount of reddish froth but a good stir dissolved it all neatly. (Each tablet was 4g so this presumably meant 24g of miscellaneous other crap ended up in the mix – probably mostly sugar)
  • Add 20g of the cheapest instant coffee Morrisons had on offer – their own-brand stuff, tucked away at the bottom of a shelf. Stir this, again, until all dissolved.
  • Let the mix stand for a good ten minutes at least. (I did this in a warming bath to make sure it was up to about 20-22C, since it was a cold room)

Then develop promptly, don’t let it stand too long – I tried to pour carefully to avoid any sediment from the tablets/coffee, but there didn’t seem to be much. For this film, the recommendation was 13m30, initial agitation then a couple of inversions every minute – a bit longer than I’m used to but sure. Drain – delighting in the fact that this is fine to just go down the sink – and rinse with running water as a stop bath. I gave it a little longer than usual for rinsing (maybe 1m30-2m?) since it was still coming out brown-tinged after a minute.

Finally, fix – I was very cautious here as my fixer had ended up a bit ominously tinted after the last botched attempt, and had been sat out all night, plus Bergger recommend a longer fixing time anyway. So I erred wildly on the side of caution and gave it nine minutes.

And it worked! Some very fogged images and I may try some of the variant recipes in future – adding a little potassium bromide or iodised salt helps with this apparently? But it is also possible that when we get better light, trying this with 100 speed film will work much more nicely.