Caffenol-C-M Underdevelopment Troubleshooting
So I just tried Reinhold's Caffenol-C-M recipe (http://caffenol.blogspot.com/search/label/recipe) for the first time. My negatives appear really underdeveloped, and I'd appreciate any assistance in identifying where I screwed up. :-D
The film was Neopan Acros in 120 exposed at 100 ISO in open shade.
Development was 15 minutes at 19-20 C.
-- Gentle agitation for 30 seconds during first minute.
-- Gentle agitation for 5-10 seconds every minute thereafter.
1 minute cold tap water stop bath.
5 minutes Photographers' Formulary TF-5 fix.
5 minutes cold tap water wash.
I mixed the Caffenol-C-M as follows, in the order that follows:
-- 1000ml distilled water at ~35 C
-- 54g Arm & Hammer "Super Washing Soda"
-- 16g Anhydrous Citric Acid from the Photographers' Formulary (from a new, sealed bottle)
-- 40g Valutime Instant Coffee: Original Roast. ("100% Coffee")
(All dry ingredients were measured with an inexpensive digital scale that purported to have 0.1g precision.)
The citric acid foamed like crazy when I added it to the solution, but I waited until it was clear of bubbles before adding the instant coffee. I may not have waited long enough for all microbubbles to dissipate, but there were no obvious bubbles in the solution.
After mixing the developer, I put it in an ice bath to bring it down to 20 C before using it to develop my film. It may have dipped to 19 C (or even slightly lower) over the course of the 15 minute development; I was working in a cold garage.
After searching through other Caffenol-C-M help requests, I thought that my Arm & Hammer super washing soda might not have been water free. So, this morning, I heated it up in my oven in a glass beaker to find out.
Original Sample Weight: 136.5g
After 1 Hour at 170F: 136g
(At this point, I decided to move the heated washing soda powder to a small dish to try to increase the surface area exposed to heat, to see whether that would make a difference.)
After 2 Hours at 170F: 134.7g
So, after 2 hours at 170F, the washing soda has lost less than 2% water weight. I'm comfortable saying that I used "waterfree" washing soda. I wasn't using super rigorous lab technique or great instruments for my single sample analysis, but I'm pretty darn sure that the ingredient I used wasn't monohydrate or decahydrate washing soda.
So, at this point, I think that there might be three potential errors that affected my development:
1. My instant coffee didn't have enough caffeic acid.
2. I didn't wait long enough after adding the fizzing anhydrous citric acid before adding the coffee.
3. I either didn't agitate vigorously enough or my development temperature fell well below 20 C without me noticing.
The negatives, including frame numbers, are very faint. I was able to pull an image out of them (attached), but the histogram I've attached shows how thin the image is.
Thanks in advance for any assistance!
Pat (Caffenol-C-M Test) by Cuckoo Wasp, on Flickr
Caffenol-C-M-Histogram by Cuckoo Wasp, on Flickr
Did you actually use Citric Acid or is that a typo?
Caffenol-C & variants use Ascorbic Acid
The real chemists will have to chime in about Citric Acid as a developing agent, but I don't think it is one ... if so, the only developing agent in your brew would have been the Caffeic Acid in the coffee
Argh, that's it. Complete goof on my part! Now I feel like an idiot. :-)
don't feel bad, you may have just discovered another variant.
Originally Posted by dpn
i know citric acid is sometimes used as a stop bath, but who knows
maybe you have realized it can be used in caffenol as well.
your negatives look nice, hows the grain
my stew always foams like mad when i mix in the vit c ...
As I understand it John, the "original" Caffenol used just coffee, water and some alkali (Bicarb & Hydroxide) but the development time was 25 minutes!
There's a link in the caffenol cookbook to the original research report: http://people.rit.edu/andpph/text-coffee.html
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Citric acid is not a developing agent nor can I remember anyone on APUG ever saying that it was. The Kendall-Pelz Rule can be used to identify whether an organic chemical is a developing agent or not.
A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.
~Antoine de Saint-Exupery
Citric acid kills the working pH and so the developer. Add bicarbonate and sugar and you will have a sparkling lemonade
And please don't use bicarbonate as mentioned 2 posts before but washing soda for Caffenol-C-M and other Caffenol variants. Dr. Scott Williams pH-adjustment was done differently with bicarbonate AND pot. hydroxide.
Last edited by grommi; 01-01-2013 at 10:12 PM. Click to view previous post history.
which is exactly what my post said.
Originally Posted by grommi
no suggestion that bicarb should be used
Yes, pdeeh, 100 % right. I only thought it needs to be confirmed/inforced. You can't imagine what people think they can use for making a developer and creatively interprete recipes. F.e. laundry bleach instead of washing soda..... I often get inquiries why this or that Caffenol recipe doesn't work. For 99,9 % wrong ingredients are used. But since reading and realising has become so uncool I doubt my remark was helpful.
Originally Posted by pdeeh
BTW, by far the most frequent error making Caffenol is using hydrated washing soda instead of the waterfree/anhydrous without recalculating the amounts. It's so easy to check in th the kitchen .... sigh
Best - Reinhold
Last edited by grommi; 01-03-2013 at 09:25 AM. Click to view previous post history.