Caffenol: Developing Film with Coffee, an Intro
Ask any analog photographer who has developed their own film and they will talk your ear off. They will wax eloquent about the process and the romance of the whole doing-it-yourself-in-the-darkroom. It’s intoxicating, I admit, and not in a chemically-induced way. There’s a mystique around developing your own film rather than waiting for the film to return from the lab. You get more of an “ohhhh” effect when you first take out freshly developed film that you did yourself; you don’t get that feeling when you finally get your film back from CVS.
There are quite a few ways to develop film, but they all rely on the same basic process: an acid is applied to the exposed film, another acid is used to stop development, and a fixer is applied to “fix” or prevent the film from reacting further to light. Really simple process overall.
Typically, developer is made up of hydroquinone, phenidone, or dimezone. All of which are acidic. Acid is needed to bring out the silver halides in the film. Sometimes other chemicals are used to increase the acidity like sodium hydroxide or sodium carbonate. A stop bath is added to prevent over-exposing the film by halting the developer and washing it completely away. An acetic acid is used in this step, however, water and very thorough rinsing to wash away remaining developer may also be used (there’s a lot of debate over this aspect, but if you do it thoroughly and quickly, like I do, you never notice a difference). Lastly, the fixer. This step is typically made up of using either ammonium thiosulfate or sodium thiosulfate. The fixer washes away any unexposed silver in the film and preventing any further reaction to light. The image is now “fixed” on the film. Clever name, eh?
So, with names like acetic acid and hydroquinone, one has to wonder . . . are these chemicals really necessary? They can be, but that’s not what Caffenol is all about. Back in 1995, a clever bloke who goes by the name of Dr. Scott Williams, PHd of Rochester Institute of Technology (RIT) discovered an alternative way to develop black and white film using household items that aren’t toxic and can be bought at your local market or pharmacy. And, it’s so easy that a caveman can do it!
The Ingredients
Caffeic acid: This can be found in any number of things like coffee, tea, wine, or spirits. Instant coffee is more commonly used. It’s not the caffeine we’re after, but the caffeic acid. So, buy the cheapest instant coffee you can find, especially if it’s labeled “strong”. Right now I have a big ol’ tub of Folger’s in my chemical arsenal. Make sure you buy crap-coffee, because it’s useless afterwards when you use it to develop film so there’s no sense in buying Starbucks for this.
Vitamin-C: In powdered form! You can find this easily in health food stores and those vitamin shoppes that only huge bodybuilders (and wannabes) frequent for their protein shakes. “C” works as a second developer and helps give the film more contrast. A lot of recipes omit C, but I think it’s essential. Plus, C plays well with caffeic acid, so it assists in speeding up developing time (which is already long enough with caffenol than regular developer).
Washing Soda: Soda is used as a pH modifier which helps make the caffenol solution more alkaline. It’s big job is to activate the developing agents thus making the whole song-and-dance happen. Most problems with caffenol originate with the washing soda, which must be “water-free” or “anhydrous”. Baking soda will not work! If your soda has water in it, it must be cooked out. In other words, pain-in-the-butt. So, just buy proper washing soda and save yourself from putting yourself in the poor house via the Swear Jar when your film comes out under-developed, or not at all.
Potassium Bromide: Ok, this one isn’t exactly a household item, however its replacements are. Bromide is used as a restrainer and anti-fogging agent. It basically keeps the developer in check and not going hog-wild. Fast films (+400iso) and anyone who develops using the “standing” method (more on that later with Caffenol C-L) should absolutely use it. Iodized salt works as a replacement to bromide, just use 10x the stated amount of bromide. Regular non-iodized table salt may be used in a pinch [cue, rimshot], just use 20x the stated amount of bromide. Ideally, use bromide. If you don’t have some and you’re just starting out and your film is ‘slow’, go with the salt.
Dihydrogen Monoxide: Water, Helen. Water. If you have funky water—or if you live in Flint, Michigan—it might be a good idea to use demineralized water. Personally, I’ve never had an issue with tap water. After all, this whole process is about simplification, so keep it simple! The only boggle with water is you want to maintain a pretty consistent temperature. So, use a thermometer, or, better yet, a Sous-vide machine, if you have one. I use one and it simplifies the whole process! Keeping the developing tank in a tub fitted with a sous-vide machine keeps the temperature very consistent, which comes in handy for standing development.
Process
Ok, now comes the fun part! Choose your recipe and gather your ingredients! (All ingredients below are measured per liter. Also, I’m going to assume you know something about developing film.)
Caffenol C-M and Caffenol C-H, below, both require the same process, however their ingredients vary slightly and they are used for slightly different reasons.
Caffenol C-M
Used for medium speed films
Used if pulling/pushing film is needed
54 g Washing Soda
16g Vitamin-C
40g Instant Coffee
Caffenol C-H
Used for general purpose developing
54g Washing Soda
16g Vitamin-C
1g Potassium Bromide
40g Instant Coffee
Pour 1L of 20˚C water into a beaker or measuring glass. Mix in ingredients in order being sure each addition is completely dissolved before adding the next one. Let rest 5 mins for coffee to fully dissolve.
Pour into film canister and agitate for 10 seconds each minute for 15 minutes.
Pour out Caffenol and rinse thoroughly with water.
Add fixer for 6 mins, agitating every 50 seconds for 10 seconds.
Dry and hang, as normal
Caffenol C-L
Used for general purpose developing
Used when finer grain is needed for slow film
Note: This process involves Standing Development which means the solution is left alone during the majority of the development phase. There is very little agitation, so make sure each ingredient is thoroughly dissolved before adding the next one. Potassium bromide is important for this process! 1.5g is a suggestion. I usually do between 1g and 2g depending on how contrasty I want my film to be.
16g Washing Soda
10g Vitamin-C
1.5g Potassium Bromide
40g Instant Coffee
Pour 1L of 20˚C water into a beaker or measuring glass. Mix in ingredients in order being sure each addition is completely dissolved before adding the next one. Let rest 5 mins for coffee to fully dissolve.
Mix into film canister and agitate for first 30 seconds. Leave standing for 70 minutes.
Pour out Caffenol and rinse thoroughly with water.
Add fixer for 6 mins, agitating every 50 seconds for 10 seconds.
Dry and hang as normal.
Final Thoughts
Personally, Caffenol C-L is my go-to developer for Caffenol developing. I’ve had the most luck with it and it produces very low-grain and yummy contrast. C-L takes much longer than regular developer, which takes about 7 minutes. But, C-L yields the best results of any alternative developer I’ve had the pleasure to use so far.
A couple of things to keep in mind:
Caffenol developer can not be stored before or after use. Mix it, let it rest for 5 minutes, use it, and pour it down the drain. No, you can’t use it for coffee in the morning (yuck). This stuff smells like dog food when you mix it. (double yuck).
Keep the temperature as consistent as you can throughout development. Since I prefer the C-L, which stands for over an hour, this is why I use my sous-vide.
Do not use it on anything uber-important! Caffenol can fail easily if your washing soda is corrupted.
Caffenol will more than likely stain your film brown. This isn’t incredibly important overall, just don’t be shocked when you take it out of the solution.
Examples
