I had my doubts about this process. Yes, I'd seen other people do it on other blogs but you know how things go -- it never quite works the same at home.
First things first, I gave away all my darkroom equipment years ago, so I spent some time trying to think what improvised devices I had around the house that might be lightproof. I debated an old coffee can with aluminum foil inside the plastic lid or a stainless steel drink shaker. However, both of those solutions gave no provision to the spooling of the film to keep it from touching itself or the walls of the container. It would have also taken some clever engineering to come up with a way to pour chemicals in and out without light leaks. Therefore, I decided it was easiest to pick up a second hand development tank. I posted an ad looking for a free one on craigslist but only found incredibly wishful people wanting to sell me their entire darkroom labs for several hundred dollars. I decided to check eBay and for $15 (shipping included) I ended up with a 500ml stainless steel Omega developing tank with two film spools.
Next I started collecting my developer ingredients: instant coffee, washing soda, and vitamin C.
I read that you could use white vinegar as a stop bath, but I decided several thorough rinses would be good enough.
I had read on some forum that seawater could be used as a fixer. Pursuing this research, I found out this was not true. The only known chemicals that can rinse the silver from the negatives and do proper fixing are sodium thiosulfate or ammonium thiosulfate. There are some pool chemicals used to dechlorinate water that use sodium thiosulfate, but I figured buying pool chemicals was no better than buying actual fixer.
Having to buy fixer kind of ruins the MacGuyver hipster cred of this entire process, but oh well.
Here's all my supplies.
Total cost for this experiment (not counting film) is as follows:
Developing tank & reels $15 (eBay)
Instant Coffee $6
Vitamin C pills $7
Washing Soda $2.50
(It's probably worth noting that the combined cost of the coffee vitamin C and washing soda was $15.50 and a bottle of Kodak T-MAX developer is only $11.50. Unfortunately, there's no big cost savings to this method.)
I was using Kodak T-MAX 100 film in my Leica M3, so I used Reinhold's Caffenol-C recipe but reformulated to make exactly 500ml.
50ml washing soda
8g vitamin C (They were 1,000mg tablets, so I used 8 tablets.)
80ml instant coffee
The vitamin C was in pill form, so I put them in an envelope and gently crushed them into powder with a hammer before starting.
I used a graduated measuring pitcher and a blender bottle with graduated markings on the side for my measurements.
Step 1) Put the water in the bottle. (I added a couple ice cubes to bring the temperature down to 68 degrees fahrenheit. They were gone by the time I finished mixing, but it kept the developer cool.)
Step 2) Add the washing soda and mix.
Step 3) Add the vitamin C and mix.
Step 4) Add the coffee and mix.
(The upside to using a blender bottle is that it mixes things VERY well. The downside is that the wire whisk aerates the liquid and causes a foamy head on top. Foam will not do a good job developing negatives.)
Step 5) Wait 5 minutes for foam to settle.
At 68 degrees f, I developed the film for 15 minutes. I poured the developer into the tank and agitated it for the first 30 seconds. Then I agitated it again 3 times at the top of each minute.
After 15 minutes, I poured out the coffee and filled and rinsed the tank several times with tap water.
I didn't have a large container for the fixer, so I re-calculated the formulation to make 500ml of that in the blender bottle as well. Here's the recipe:
125ml Solution A
14ml Solution B
Then add water until you have 500ml.
The instructions said to allow it fix for 3-5 minutes, so I went with 4 minutes. I poured in the fixer and agitated it for the first 30 seconds, then I gave it a couple tips at the top of each minute.
I poured out the fixer (which can be re-used for multiple rolls of film) and then rinsed the cannister again.
I held my breath as I popped open the lid, but I was relieved to find pictures printed on my negatives.
I haven't invested in a negative scanner yet, so I attempted to scan the negatives on my flatbed scanner by holding a light above them, but I couldn't get a usable scan. Plus, my scanner maxes out at 600dpi, so the print would only be twice the size of the 35mm negative.
Having failed at scanning, I decided to lay the negatives across my softbox and use the macro lens I built for my X1 to snap a photo. That worked better than scanning but I still didn't get the negative as flat as it should be and the texture of the softbox showed through the negatives.
Once I finally had a somewhat usable digital file, I pulled it into Photoshop, inverted the color and cropped it to size.
I'm sure old Sam Houston will look much better once he's scanned properly, but even at this poor resolution, I think there's plenty of proof that instant coffee is a great developer. I'm going to buy more T-MAX 100 and get back to shooting.