Mixing It Up With Caffenol

Run out of your usual black and white developer? No longer have a traditional film store in your local high street? Annoyed by people asking you rhetorical questions? Then pop in to town and pick up a jar of cheap instant coffee, some soda crystals, and a dash of powdered vitamin C. Mix with water and voilĂ  : you have caffenol.

Here’s What You’ll Need

Instant Coffee: Coffee contains caffeic acid, which acts as the developing agent. Any old cheap rubbish will do by all accounts. I bought the cheapest and nastiest stuff I could find.

Soda Crystals: A developer needs to be alkaline to work, but coffee is fairly acidic. That’s where soda crystals come in. Adding them to the mix raises the PH and allows the development process to kick in.

One thing I found from my research that you don’t often see mentioned, is the different types of soda crystals. Most recipes you find online assume the soda crystals are anhydrous (i.e. water free). However, here in the UK the most common brand you’re likely to come across is Dri-Pack Crystals. These are not anhydrous, and people who are smarter and have more time on their hands than me have worked out you should multiply the amount by 2.7 to compensate for this.

Powdered Vitamin C: This considerably speeds up the developing time, making the process more practical. You should be able to pick this up from a pharmacist or health food store like Holland & Bollocks. Strictly speaking what I’m making here is known as caffenol-C. You can make plain old vanilla caffenol without the vitamin C – the only difference is you’ll be hanging around for a lot longer.

The Quantities

To make 1 litre:

  • 150g Dri-Pak Soda Crystals
  • 16g Vitamin-C powder
  • 40g Instant Coffee
  • Water to make 1000ml of solution

I don’t think this stuff really keeps, so it’s best to mix only what you need. Here are the minimum amounts to process a single roll of 35mm and 120 in a paterson tank:

35mm

  • 45g Dri-Pak Soda Crystals
  • 4.8g Vitamin-C powder
  • 12g Instant Coffee
  • Water to make 300ml of solution

120

  • 90g Dri-Pak Soda Crystals
  • 9.6g Vitamin-C powder
  • 24g Instant Coffee
  • Water to make 600ml of solution

The Method

  • Fill the beaker with half the target amount of water. In other words, 300ml if you want to create 600ml of developer.
  • Add in the soda crystals and stir for a good few minutes until dissolved. This seems to quickly lower the temperature by about 10℃. If I had a clue about chemistry I might be able to tell you why.
  • Vitamin C next; make sure it’s properly stirred-in.
  • Repeat as above with the coffee. Things don’t look or smell too good at this stage.
  • Top up with water to the desired level; 600ml in this example. Mix.
  • It’s probably a good idea to let it rest for 5 minutes or so, just to let the bubbles settle. You can use this time to get it to the pre-requiste 20℃ whilst you’re waiting. Putting the beaker in a bowl of hot water is good for raising the temperature. To lower the temperature of my developer I always use the genius invention that is plastic ice cubes.
  • From here on you can develop as normal, at the usual temperature of 20℃. For this roll of Tri-X 12 minutes worked well for me. After emptying the developer down the sink, give the tank a good rinse with water rather than using stop (I rarely use stop these days), and fix and rinse as normal.

In was really surprised how well these pictures came out. I thought they’d be some compromise; that they wouldn’t be particularly sharp or perhaps too grainy. But this seems to work as well as any other developer. I don’t know how often I’ll be using Caffenol in the future, but I’ll certainly keep the ingredients handy in the cupboard in case of emergencies.

All photos taken with Yashica Mat on Kodak Tri-X. Developed in Caffenol-C for 12 minutes