Introduction: Caffenol-C: Coffee Film Developer
To develop a roll of film and make negatives for printing, it is necessary to strip the film's exposed silver halides. Usually, this is done with conventional developing solutions. Since the developer is the primary ingredient in the process, a lot of it is used. Unfortunately, the developer is one of the most problematic chemicals used in photography. It's awful for the environment, and it can be expensive. It smells pretty nasty, too. (Fixer, a chemical used later in the process to preserve the negatives, has similar issues, but it won't be covered in this article.) Developing solutions are even worse after they've been used. Most of the silver halides from the film are washed away in the developer (some are left over until the stop bath), leaving you with a chemical that you can't just toss in the yard.
To get rid of used developer, it has to be stored until it can be taken for hazardous waste disposal. Before I learned all this, I was used to tossing my bucket of chemicals into the soil in my backyard. It was pretty close to a storm drain, too. Not all that cool. It would be great to have a developing solution that could be thrown out the window, but even Caffenol won't get us that far (ugh, silver!). Using it as an alternative developer, however, will reduce the nastiness and eye-burning odor a bit. Even better, it's cheap! You don't often see greener options that are cheaper than their nasty counterparts.
Caffenol is a developer consisting of only washing soda (which is used commonly as a laundry detergent), coffee crystals (like Instant Folgers), and sometimes vitamin C (for making Caffenol-C). It replaces the commercial developing chemical in developing black and white film. It was introduced seventeen years ago by Dr. Scott Williams and his class at the Rochester Institute of Technology when he experimented with his class to find a household developer. After reading a bit about Caffenol, I followed the instructions on the Photojojo blog (link below), so the steps here are based off of their methods and tips from some helpful photographers at the printing lab.
Note: Every photograph in this article, with the exception of three stock images, is shot in black-and-white and developed with Caffenol-C.
Helpful links and sources:
Step 1: Collecting and Prepping Supplies
I managed to get all of my supplies from the local hardware store, photography lab, and under my sink. It's not too hard.
From the photo store:
Film, if you don't already have a roll that you want to develop
A daylight developing tank - nothing specific, just don't forget a matching spool!
Changing bag or a dark room
Fixer - I use Kodak Professional
Optional: Brown chemical storage jug (or two)
From the hardware store:
Washing Soda - I use Arm & Hammer (not baking soda)
A few measuring cylinders - 16 oz. each
Large glass cups, unless you already have some that you're willing to clean well
You might already have all of these things. They're pretty common, you know.
From under the sink:
Vitamin C powder - You might need to get this at a drugstore or online.
Instant coffee crystals - Well, it's above the sink, but hey.
An eency bit of dishwashing liquid soap
Bottle opener and scissors
A few gallons of water - Get it from the hose, nearby pond, doesn't need to be fancy.
A clothespin or binder clip
Once you're finished with the process, you'll be left with a strip of negatives that will need to be cut and sent to a photo lab for printing, unless you have a negative scanner or you're able to print them yourself.
Fill two glasses with 6 oz. of water each. Mix 5 teaspoons of instant coffee crystals and between 3/4 and 1 whole teaspoon of vitamin C (see step five for more detail) into the first glass. Mix 3-1/2 teaspoons of washing soda into the second glass. Don't leave too many lumps! When everything's mixed, stir the two solutions together in a single glass. Ta-da! It's Caffenol-C!
Follow the instructions on the bag your fixing chemical came in to make a batch. I decided to mix my whole bag at once and keep it in a brown chemical jug under the counter. It should last for a while, and you can reuse fixer a few times.
Fill another clean glass with water and stir in a few drops of dishwashing liquid. It doesn't need to be specific, it'll just be used to wash the fixer and other leftovers off of your film. Don't get too many bubbles, though, since it can be a pain to pull your film out of a bucket of foam.
Step 2: Loading Film and Checking Your Station
If you're using a changing bag, follow the instructions in italics and then move on to the next step.
Open up the changing bag and put the exposed film canister, daylight developing tank, bottle opener, and pair of scissors inside. Be sure to close allof the zippers! Then, roll up your sleeves and stick your arms in the bag.
Make sure there aren't any light leaks in the changing bag or darkroom. Use the bottle opener to open the canister, and cut the film strip off of its spool. Cut tiny little corners off of one end of the strip. They shouldn't be too big, just about one square millimeter triangles. Wind the strip onto the reel that fits into the tank, winding trimmed-end first. Put the reel back in its tank and close everything up before opening the changing bag and removing the items.
At this point, you'll want to have:
• A loaded developing tank
• Three glasses of mixtures - Caffenol-C, soapy water, and fixer
• A few gallons of water nearby - a hose works well
• A stopwatch
• A rag to keep things nice and dry
• Various chemical containers to hold reusable fixer and Caffenol, and nasty water
• Music (iPod, laptop) since there's a bit of waiting time involved
• A clothespin or binder clip
Step 3: Developing, Stopping, Fixing, and Washing
Hurray! This is the slow and tedious part.
Make sure the developing tank lid is screwed on really, really tight. Then, take the rubber cap off the top. There might be an agitating rod, which you should remove as well. Slowly pour in the Caffenol-C mix. When you've finished off the cup, put the cap and the agitating rod back on the tank and immediately start the stopwatch. Begin agitating (flipping the tank upside down again and again) the tank slowly for one minute. Agitate thrice every minute until the stopwatch reads 12:00. That's one minute agitating nonstop, eleven minutes agitating three times per minute. When it's finished, take off the cap and the agitating rod and dump the soup in a storage bucket.
Fill the tank with water, and cap it. Agitate six times. Dump this water in the container with the Caffenol-C, or find a new bucket and save the developer for reuse once or twice more. Repeat this step twice more for three rinses in total.
Fill the tank with fixer, and continue to cap and uncap when it makes sense, of course. Reset the stopwatch quickly and start it up again. Agitate thrice each minute for seven minutes. I've heard it's better to go past the set time than under the set time. When finished, dump the fixer into a container. I'd recommend a second container for used fixer, as long as you mark how many times it has been used.
Fill the tank with water. Agitate thrice. Pour the water out. Fill the tank again with water. Agitate six times. Pour the water out. Fill the tank one last time with water. Agitate twelve times. Pour the water out. Bored yet?
Pour that glass of soapy water into the tank. It doesn't need to be filled. Agitate slowly twenty-four (24) times. Pour the soapy water out.
Step 4: Drying and Printing
Unscrew the main lid of the developing tank and take out the spool. It's covered in bubbles and soap. Don't fret. If you're using an oscillating plastic spool/reel, you should be able to slide the disks apart and pull the negative strip right out. If you're using a fixed metal spool/reel, you should be able to unwind the negative strip.
With your fingers or a squeegee, wipe most of the suds off the strip. You could even go the extra mile towards minimizing streaks and wipe it down gently with a photographic sponge (recommended). Hang the strip up on a shelf or something tall with a clothespin or binder clip and cut the unexposed ends off (optional).
Leave the film hanging overnight, or twenty-four hours if you want to be absolutely sure it stays straight.
I've never had the pleasure of printing from negatives myself, so you'll have to find another 'able for that. However, there's nothing wrong with getting your negatives scanned at your neighborhood photo store. Asking for prints is fine, too, but you'll sacrifice a bit of quality (though there isn't a whole lot in the first place if you're just starting off with Caffenol). I go to Marin Filmworks in the Bay Area (http://marinfilmworks.com/), and I love them. I received great help researching Caffenol and other alternative development techniques during some visits in the last year. Sorry for the bit of advertising, but I like supporting one of my favorite local businesses.
Enjoy your beautiful, unique photographs!
Step 5: Extra: the Effects of Vitamin C
When I first heard about Caffenol and Caffenol-C, I read a couple of comments questioning the addition of vitamin C. The responses suggested it reduced fogging and shortened the developing time. I decided to test how varying the amounts of C affected the contrast of final prints if I kept a constant developing time. The experiments weren't the most thorough, but I managed to get an idea of what the C was doing.
I exposed six rolls of film with shots of a black-to-white grayscale chart. I developed one without vitamin C (image #1), one with 1/4 teaspoon (image #2), one with 1/2 teaspoon (image #3), one with 3/4 teaspoon (image #4), one with 1 teaspoon (image #5), and one with 5/4 teaspoons (image #6). To measure the contrast of the final scans, I cropped chunks (image #7) from each black section and each white section of the sets, then tried to average the shade and find it's hex. value with whatsitscolor.com. It may not have been the most efficient method, but I ended up with a graph (image #8) that made sense.
The trend lines dip inward at the 5/4 mark, which leads me to believe that the vitamin C is affecting the development speed. With more C, the film was over-developing, and losing contrast while getting grainier. With the graph shown below, I was able to see what I'd expect to be a "sweet spot" for developing film with peak contrast. This may not be what one wants, however. Photojojo suggests less C. I think it's still worth experimenting solo to find the best combination of vitamin C and developing time for you.