Caffinol…? That’s old school. Have you tried any of the Polyphenol developer alternatives?
By now most everyone who follows analog/film photography has heard of or has seen film developed in Caffenol. In the mid-90’s at RIT the chemistry majors were presented with a class project: If kodak was shut down by the EPA and you had some film to develop, how would you do so with stuff under your kitchen sink? The class discovered that Coffee, Vitamin C (Ascorbic Acid) and Wash Soda (Sodium Carbonate) would develop film. Coffee contains Polyphenols in the caffeic acid, Vitamin c is a super-additive and the wash soda( sodium carbonate) is the alkali accelerator .
Since then we have seen people using beer, red wine and other “hipster” variations. I can think of better things to do with beer and red wine at that price point and while I like the smell of coffee by itself, Caffenol stinks when you add the carbonate – it smells like an old burnt forgotten pot left to boil dry… just nasty!
My Philosophy of Home brewing
I hang out & post in a few Facebook groups and try to encourage people to mix their own chems if they have the slightest inclination. It angers me when people post questions regarding alternative home brews and others reply with derisive remarks like “oh why bother? or ” the results look grubby & inferior” or even worse, “if you can’t afford D76 maybe you should consider a less expensive hobby”.
Photography is SUBJECTIVE. I can tell you what my TASTES are, but I have NO business saying any ones images are inferior!
Why try Polyphenol Developer Alternatives?
Recently with COVID concerns many resellers had shipping interruptions. A few stores said no more shipping Rodinal (caustic ground freight restrictions). Spotty backorder situations were hitting users here & there. But, aside from these temporary supply inconveniences I still site the following reasons to consider making your own chems:
- Some of the components can be had freely
- The quality is not compromised
- Experimenting is fun
- Your darkroom can smell wonderful
- Concerns about toxic substances are lessened – so less worries about skin dermatitis or carcinogens.
What’s in YOUR garden or spice rack?
Let’s dive into that first Bullet Point above – the free components. Who gets Instant Coffee for free – or beer or wine? Nobody I know. But there are 35 other common herbs, spices & foodstuffs that have more polyphenols than coffee, I live in the very “spartan” desert of Southern Arizona and actually had 3 sources of polyphenols in my yard. We planted a rosemary bush a few years ago as my wife likes to add a sprig to roasts & stews. Two indigenous trees, Mesquite and Palo Verde produce seed pods seasonally and they contain a lot of polyphenols. I literally have maybe 50lbs of mesquite seed pods I can rake up & bag up laying in the dirt at the moment. 10g will process a roll – so will 5g of fresh rosemary or 2.5g of dried. It doesn’t take much.
Here is a table of commonly found items and their polyphenol content. That content column is MG per 100G
The math they told you that you’d never use…
As we see from this table coffee is ranked #36 and cloves #1. One of the standard Caffenol formulas calls for 15g Carbonate, 2.5g ascorbic and 10g instant coffee for 300ml of water for a single roll. How much Clove might be needed? If we divide the 214mg/100g content of the coffee into the 15,188 of the clove then we might need 1/70 the amount of clove to coffee. Keep in mind that using home methods of hot water steeping/making tea of the desired substance we cannot extract EVERY drop of the goods from the target item. 10g of Coffee divided by 70 is roughly 0.15g of cloves. I made an educated guess and used 0.2g cloves , and the same 15g carbonate and 2.5g ascorbic acid (vitamin c) with the 12 min caffenol time and achieved this:
Expired Soviet Mikrat 300 from 1981. Not bad. The cost of 0.2g of ground cloves from my kitchen spices along with 2.5g of vitamin c powder ($18/kg on amazon) and 15g of Arm & Hammer Wash Soda is fairly negligible and if you like the smell of cloves it was very aromatic.
What about free garden stuff? Let’s look at the rosemary shrub I mentioned earlier . Rosemary is 1018 vs the 214 for Coffee—about 5 times as potent.. Using the same math it would be assumptive that I would need about 2g of dried rosemary I took 2 sprigs that weighed 5g total and dried them for a week—dried weight was 2.5g. I boiled these for a tea and added the same content of the carbonate & ascorbic and got this:
Now, one word on the different polyphenols is that you will likely have to play with your times. Rosemary was VERY active and the time for this was only 8 minutes. It also had a very pleasant smell.
Mesquite seed pods—slightly sweet tea smell:
Palo Verde—same light sweet smell:
Aside from speed properties we can see that some will impact contrast as well
Menthol Crystals—very strong mint smell (my wife loved it):
The Menthol Crystals were a suggestion from a chemistry student who stated in one of the facebook forums that menthol was chemically akin to metol menthol chemical structure similar to metol that’s why I’m curious about it, though it has one OH binding site compared to Metol. For a few bucks I bought some menthol crystals and 0.7g works well for a roll of film. You can make a mint tea from leaf but I figured if the crystals didn’t work I could add some to my hand sanitizer.
So, in closing, you have a lot of choices. Many may be free from your garden or at a very low price from your grocery store. Just substitute the coffee in a caffinol formula & plug in any one of a number of other sources of polyphenols. What grows well or is readily available in your country? Curry in India? Cloves in Indonesia, Mint in a British garden, Basil & Oregano in Italy, Thyme in Germany & so on. Experiment and have fun in the process.
Some obligatory disclaimers:
Don’t defoliate an area and be a pig- snip just what you need and leave the plant to recover from the pruning
Don’t trespass into someone else’s garden (ask first). Some public lands it’s a BIG no-no to take anything.
Some people will also try to suggest that you can use just ascorbic acid & carbonate to process film–these other substances do nothing. In answer to that I attempted a test in just the 15g of carbonate and 2.5g ascorbic and the outcome was very sub-standard. Underdeveloped with muddy tones and a lot of base fog. Using Caffinol as the base line and using the exact same amount of carbonate & ascorbic my observations were that rosemary cut the time in half and could be used to push film. Palo Verde boosted contrast. Cloves gave a deep black and more grain using same time as caffinol. Menthol crystals needed more time and had a very clean base. If these other substances did nothing wouldn’t the outcomes be consistent if the amount of carbonate & ascorbic were the same? While some of these on their own will not trigger development they react with the ascorbic and trigger super-additivity. Just like Xtol has ascorbic AND Phenidone or 510Pyro has ascorbic AND pyrogallic acid–it makes a difference.
Tucson Az USA
12.31.2020– Footnotes/additional info on using menthol crystals. This mix works WITH some important caveats. Menthol Crystals melt at 95F/35c and dissolve easily in alcohol. The issue is that if you put the alcohol dilution in COLD water (normal 68f/20c for B&W) the menthol wants to start congealing again. In my tests I still had development but with some films I had what I would call “abrasions” or scuffed emulsion. I have retested that problematic film and came up with these procedures and cautionary:
Mix a 10% solution of denatured or grain alcohol and the menthol crystals. That is to say, any mathematical permutation of 100ml alcohol to 10g of menthol crystals. I use recycled kombucha bottles and opted to use 400ml alcohol to 40g of the menthol crystals, The menthol stays in solution–no issues. In previous tests the development times were long compares to the Rosemary. The following procedure resolves the excessive time and the emulsion damage.
Heat 300ml water to 100f/38c
15g sodium carbonate-stir to dissolve
2.5g ascorbic acid-stir to dissolve
7ml of the 10% solution of alcohol/menthol
The “tropical” temperature will allow the menthol to stay in a liquid form and cut dev time substantially. The film I had issues with was some Mikrat200 soviet film. Other films also required long times at the cooler temps but this film did NOT do well in the mix at all. Using the very warm water and times of 6 minutes I achieved the following:
Obviously, this is but one film type. I let the mix cool a bit and the menthol started to congeal– I tested another short snip and the previously mentioned damage manifested itself in spots. This is why the warm mix is critical to it’s success. All & all, I’d say your best bet is going to be Rosemary, Ground Cloves and Curry powder to my eye.
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56 thoughts on “Polyphenol Developer Alternatives – A World full of Options – By Daniel Keating”
Fabulous article. Being a long time advocate of herbal and holistic cures for common ills, I really appreciate this answer to the debacles of film development and the their lovely health issues. The fact that this also works with ageing film stocks makes it even more inviting, since one doesn’t need to keep differing developers lying around to spill on things and make life less pleasant. Brilliant work with the Mesquite pods as well. Nothing like harvesting an item that most take to the trash. Hope you post other of your works in the future, as I’ll be glad to read them in full.
That is a fascinating post Daniel, many thanks. I will add this post to my bookmarks and have a go with some of your natural phenols.
Personally, I have experimented with home made developers for both black and white and for colour (c41). I didn’t have a particularly enjoyable time with the coffee method and as you say, the pong was staggering.
One that I had success with and have used as a stand processor and in a more concentrated hands on approach is “Parodinal”, which is basically a copy of rodinal using paracetemol as the active phenol, 30 caplets crushed to powder, with the other fairly traditional components works and keeps as well as shop bought Rodinal.
The c41 process is still an ongoing experiment and any success has been marred by my lack of a proper understanding (or possession) of a good bleach/fix replacement. I have now resorted to buying the Cinestill powdered c41 kit, and whilst the dev part is still fresh, I am using that. The blix does not go off in the same way that the dev does, so I will be able to use the Cinestil blix with my home made dev, which according to the various blogs that I used as reference, has a far longer shelf life than the commercially made kits.
NB: I have spent quite a lot of dosh on some pretty sinister looking chemicals, some with skulls and crossbones attached, so I am doing this more for the interest and delight that messing around like this causes, than for economy.
As for the commercially available chemicals, I usually use HC110, Rodinal, or my fall back for known faulty camera work… Diafine, which is utterly fool proof.
Being an american a lot more stuff is widely available or less restricted. Nobody bats an eye at a 1000 round box of ammo left on a doorstep by the UPS man (I’m not exaggerating–I live in Tucson). All sorts of chems can be bought fairly freely here like potassium permanganate and sodium nitrate. For C41 bleach I use potassium Bromide and Potassium Ferracyanide. Aminophenol Hydrochloride is available here so actual Rodinal can be made at a cost of about $3 for a 500ml bottle
Absolutely wonderful! Thank you so much for your time and effort in putting this article together and sharing it with us all Daniel!
I have been looking at alternatives for photography chemistry for a long time and am always really interested to hear of other substances I’ve not tried before!
I wondered if you have any experience or thoughts on the alternatives to the fixers we tend to have to use? I have experimented with salt myself, but would be really interested to hear about your experiences on this too and if you have any advice to share!
Plain sodium thiosulfate crystals is what I use. 20lb bags are very cheap on Amazon. That chem is commonly used to dechlorinate ponds for Koi & other fish. I find 10g to 300ml for a single roll does the job and can be used twice. If you shoot T-grain films add 1g of sodium metabisulfite to cut fixing times
Fascinating article. I really enjoyed it. Thanks for all of your work in putting this together.
Interesting to read, Daniel. I
s there a specific order in which you have to prepare things? IIRC I read that somewhere with coffeenol. Because some ingrediants do not dissolve well when not done in the right order. I recall that from memory so I can be totally wrong.
Thanks for sharing your results and findings!
Since most of these are “teas” made by boiling the various seed pods ot plant trimmings that comes first, then the carbonate & finally the vitamin C
Daniel, being something of a traditionalist I was in the “why bother” camp after seeing the results of various brews used. That is until now, thanks to your fun article. Some results really do compare with images derived from conventional chemistry. I think when I say I much preferred the rosemary derived image you will understand why. I assume that the film is fixed with conventional chemistry?
Given the different properties that the images show, I was wondering if you’d experimented with a “mix ‘n match” for a hybrid developer to see what the effects could be? Just out of curiosity, for how long did you need to steep the dried ingredients, and does it even make a difference?
I tried a “potpourri” of 3 different phenols and the effects were kind of “flat” & unimpressive. Maybe not the right quantities of each in combination. For fixer I use plain sodium thiosulfate. I get 20lb bags for cheap on Amazon and 10g to 300ml of water will fix 2 rolls & toss. For “woody” sources like seed pods & rosemary sprigs I boil water then turn down to a low steeping heat and stew those sources for 10-15 mins then let them steep as it cools to room temp. Too vigorous or long of a boil and that can destroy the polyphenols. On one run I brought water to boil with rosemary, put the sprigs in and turned off heat and just let it steep and cool while we went shopping and it was fine.–Daniel
I’ve been using Caffenol for a long time and I find your article very interesting. I’ve immediately ordered some menthol to try it because despite the fact that the polyphenol concentration is not as high as in clove it seems like a good option and it’s significantly cheaper than instant coffee.
I was wondering whether or not there was any way to get in touch with you (other than Facebook)? Are you on Instagram or do you happen to have an email address?
When you mix the menthol crystals with warm water they will go into solution quite easily–expect some to precipitate out as the mix chills but no worries–just agitate and it will be fine. Facebook is my preferred contact point –with family, friends & former co-workers etc it makes the most sense–Daniel
Thanks for the advice. I’ve been using a magnetic stirrer for Caffenol for quite a while and I hope that it’ll work well with menthol. I’m looking forward to trying this. 🙂
I’ve had not luck with menthol. It would re-crystallise too quickly at 20 °C and it was so oily that I wouldn’t get a proper emulsion with the water. I also tried ground clover but at the amount I used (~ 1 g in boiling water, cooled down and filtered before using it) it wouldn’t develop anything at all. I’m wondering whether or not I need much more clover. The most promising was baking cocoa (de-oiled) but I also seem to have used far too little of it. I think that using clover and cocoa actually makes a lot of sense because you can reduce the cost of the developer significantly.
The menthol, to make it more soluble , i mixed 40g to 400ml of denatured alcohol (10% solution) and used 7ml (equivalent to 0.7g)
If you use just slightly warmer water with the menthol (22c) it doesnt precipitate as much. It will want to congeal slightly but it still develops. I had one film–an oddball roll of Svema where the emulsion had some marring but it *does* process film, even it it separates slightly. When you say “clover” that is a common field plant in meadows & pastures here in the US– CLOVES is the very aromatic dark brown spice used in allspice, curry powders and when not powderized you stud a roast ham with it–latin Syzygium aromaticum. I found that 1g was waaaay too much as I had a lot of staining to the neg. You are using it with the 15g of Wash Soda (sodium carbonate–NOT sodium bicarbonate?) and Ascorbic acid (Vitamin C–NOT citric acid?)
Dear Daniel. Im a skilled DIY plant-phenol developper. Just tried Menthol Crystals for the first time yesterday, and it was a DISATER :-). I mannaged to dissolve the crystals with warm water at pax 50 degrees celcius. BUT… when cooling down the developermix, the menthol re-crystalize. Not in those beautiful original clear crystals, but white clumps, like sugar.
I HOPED it would work anyways. So I poured the menthol-developer, Including the clumps into the tank, and developed 30 min, (1 stop push HP5 film). Assuming that at least some of the phenols where in the fluid water, and not all of the menthol had re-crystalized (I used a lot of menthol, probably 3 grams for 500 ml water), plus the usual amount of soda and vitamin-c, that’s works for my caffenol. I developed LOTS longer than my normal 12 min. But the film came out almost blank. Basically all the Menthol must have re-crystalized, so that no phenols were able to do the developing.
So now Ill try again. I need to find a way to make the menthol liquid. I found some hand sanitizer in the house 70% alcohol, and I used enough of that to cover for about 1/5 of the liquid. That is 1 part sanitizer + 4 parts water. GREAT, now it didn’t re-crystalize. Thats just under 15 % alcohol.
Now, Ill mix in soda + vitamin C, and develop a film.
I somewhat think, that you should revise your main article/post to explain HOW to use menthol crystal by liquifying in alcohol solution., I mean real easy-to-follow recipe. Now “down here” in the comments, I see that you recommend making a 10% solution and using 7ml of that. Nut how much menthol crystals for how much alcohol/water? And the 7 ml for how much developer.
Dont worry about me, Ill find out by experimenting. But to help others not make my mistake 🙂
I have revisited the menthol crystals in detail & for the sake of others I’m posting some in-depth “tweaks” that may help.
This is one for the hall of fame. Really amazing article. Would love to see this *ahem* further developed.
Daniel, thank you very much for sharing!
I love your post. At the moment I am using ID-11 but as soon as I am going to finish it, I will try caffenol or some of your recipes for sure. I am intrigued by these kind of experiments.
I think that not being a professional is a good escuse (if you need any) to try different things.
Also, at the moment I am collecting the used developer and I bring it to the recycling centre, so if this trick would save me some trips and also would infuse a good smell around, it is going to be even better!
I will try this in the near future, so maybe I will come back to you for some more infos 🙂
I sent you a PM via email Andrea
Great info! Thanks. I’d love to try the clove mix but I’m worried my scale isn’t accurate enough for amounts so small.
I have a very inexpensive digital “drug dealer” scale that cost $10 and will go down to 0.01g.
On a side note, my wife bought a set of steel measuring spoons with some going quite small– the “smidgin” was exactly 0.1g of cloves.
Love this article, thanks Daniel! Results from rosemary look great, I think I may give that one a go.
Rosemary is fairly common too. Our rosemary shrub was actually acquired from the hardware store at Christmas time all pruned in a triangle to make it look like a mini-christmas tree. We kept it watered over the holiday & I opted to transplant it in the yard at the new year. It took root and we’ve had it for about 10 years or so
Brilliant, just what I needed to read! Especially as I have a massive rosemary bush and plenty of mint.
I’m hoping this will trigger that sort of response Rock. Instant coffee isn’t cheap but yard prunings are and rosemary and mint have a good quality look to them
Excellent article. You don’t have any ideas on film replacements do you Daniel? That would leave analogue pretty much future proofed.
Not really–other than coating glass plates with things like silver nitrate or liquid emulsions–ok for plate cameras but not for the SLR users
@Sciolist Your question wasn’t directed to me, but you may be interested in Denise Ross’s Light Farm project.
Thanks SROYON, that’s much appreciated. I keep thinking that film will ultimately have to become biodegradable to survive, or an alternative found.
Bravo, Dan! Thanks for letting us in on your experiments. Working in a science peripheral to chemistry, I find the science of developing endlessly fascinating.
I sounds like you have a future (and past) in making All-Natural Developing! Maybe you should push the envelope and go organic. 😉
The other ingredients are fairly “organic”. Sodium Carbonate can be made from sodium bicarbonate (common baking soda) by dessicating it in a pan on the stove. Weigh out 200g and place in a small sauce pan on high heat and cook for 30 minutes. You’ll see puffs of CO2 being released as you are reducing the water content. After 30 minutes , allow to cool & re-weigh it. You should have 135g or so of sodium carbonate. Store in a glass jar so it doesn’t wick moisture back from the air. Ascorbic Acid is simply Vitamin C powder from a nutritionist shop. That’s about as organic as it gets–at least it’s all grocery store stuff
That is really a very useful article and very timely as I am planning to venture back into the self film development. My rosemary plants are about to add to their usefulness it seems 🙂
I will save this article and give it a shot, thanks
From my observations, the Rosemary was a really good choice & balance. The menthol crystals, on some films,would cause some “bruising” of the emulsion–abberations. The menthol crystals dissolve freely at about 35c. in a cool solution the menthol wants to precipitate back out but still has development. The “scum” from the menthol congealing can impact softer emulsions. Rosemary was quite versatile and had good showings in multiple film types
Thanks for this wonderful article. I’ve just had a go at making the recipe with dried rosemary and I am blown away by the result – gorgeous tones, very sharp, little grain and very easily scanned negatives.
may I ask what you did with the rosemary before you used it? Did you make a “tea”? If so, what was the exact recipe that you tried ? Do you usually use potassium bromide as suggested in the Caffenol Cookbook?
Hi Christian – sorry for the delayed reply. Yes – ‘tea’ describes it exactly. I used 3g of dried rosemary to 420 ml of very hot water. This allows for some of the liguid to be lost when straining it as it’s been absorbed by the dried herbs. I usually make 400 ml of developer for my tank (a Kaiser) to make sure the film is properly submerged. I made the tea with water just off boiling and I haven’t used Potassium Bromid up to now (though I plan to in the next batch as I am getting a little bit of fogging). I think this is all a bit to be experimented with – the recipe isn’t ever exact with kitchen chemistry! I’m very pleased with the results though – you can see some on my Flickr page.
as a side comment to Donalds post, what I do is put 450ml of water in a small sauce pan and bring it to a boil. I have used 2.5g dried OR 5g of fresh trimmings. Once the water reaches boiling I turn it down to a slow simmer and let it go for 10-15 minutes then steep while cooling. Remove the stems and place in a pyrex type beaker, As it cools to near use temperature add the carbonate & ascorbic. In lieu of Potassium Bromide you can use 4g of IODIZED table salt–the potassium iodide is also a restrainer. top the beaker off to 300ml for a single nikor reel tank or whatever volume your tank is
Thanks Daniel! I’d sort of guessed my way into that stage. I’m using dried rosemary that I bought from a herb shop so maybe it gives up its chemicals more easily. Anyway – it works!
To add to the chorus, great article! Very interesting. My wife is into essential oil extracts for various uses. Do you have any idea if polyphenols remain in essential oil extracts? I’m not sure it would be cost effective, but some oils are cheaper than others.
One draw of caffenol to me is that it’s quick to mix up because it is just a matter of dissolving everything. My film developing window is usually just an hour after the kids are in bed, so steeping and cooling would complicate this. The menthol crystals sound like they are similar (no steeping and cooling required), but they have some downsides at cooler temps. Is anyone aware of anything else high in polyphenols that can be readily dissolved like instant coffee?
In any case, I’ll have to try the rosemary and peppermint! Thanks.
I have had a “mixed bag” with essential oils. One peppermint extract commonly found here in the US is McCormick brand for baking. THAT worked well. Another more aromatherapy vendors peppermint oil was a dud. i recently acquired a mix of menthol, eucalyptus, lavender & rosemary that works well with 0.3ml with 30 mins time. And yes..menthol works a tad better at 72F/22C and i advise to make a 10% solution of the menthol crystals in alcohol–use 7ml of that for 0.7g content– less “congealing” although it still wants to come out of solution–but it still processes the film
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Thank you for this article.
I’ve been using Caffenol for a few years and I’m planning a darkroom garden at home.
One thing in my quest for the Sustainable Darkroom I am seeking is a fixative. Aside from salt water I can’t find an alternative.
Have you got any suggestions please??
Yes, while there is no plant based fixer you can easily make your own from chemicals found at hardware stores/pool & pond shops. Sodium Thiosulfate crystals are sold as pond dechlorinator. Large bags are relatively inexpensive. The next ingredient is Ammonium Sulfate (lawn fertilizer). Here in the US a 20kg bag is $15. To make a 1-shot & toss rapid fixer simply mix 1 tablespoon of the sodium thiosulfate and 1 teaspoon of the ammonium sulfate in 300ml water. Stir to dissolve. Film should fix quickly with T-grain films needing more time…fix until clear. If you want/need an acid fix add 2g citric acid powder. If you need a hardening fix add 1g alum. If you shoot old expired films a plain hypo made just from sodium thiosulfate can be used but figure on 10 minute clearing times.
Has anyone tried any of these for paper development?
I have not. But keep this in mind : The various “teas” vary in density/color. Ground cloves make a dark solution, rosemary a lighter one. All will tone paper like using coffee or tea as a “poor man’s” sepia toner. You would also need to boost the quantities used to get anywhere near normal dev times. You might get more of a showing doing “lith” process but long dev time means more staining. Vicious cycle. If you have wedding or fashion shots needing clean whites, no. If you are doing period re-enactment fake antique shots then yes it’s worth testing.
Great article! I used the info to make a cocoa developer for prints. So far so good. What I found is that more grams of cocoa powder are required than grams suggested for developing film.
Needing more for paper is a given, yes. As an example, dektol paper developer works great as a film developer diluted 1+23. Many makers marketed “universal” mixes that one would just dilute differently for film or paper.
I live in the middle of hundreds of square miles of mesquite. I saw the image of the cat and it is great, but I would like more details. Mesquite is not listed on the chart to do the math. Any suggestions?
In the section What’s in your spice rack I had this verbiage,” I literally have maybe 50lbs of mesquite seed pods I can rake up & bag up laying in the dirt at the moment. 10g will process a roll “. So make a tea of 10g of seed pods. Boil 400ml water with 10g of pods and let it steep and cool. Filter it with a coffee filter and add your ascorbic acid and sodium carbonate.
Thank you for your response. Do you grind the seed pods or just measure out 10g of seed pods with the beans in them and go? How long do you boil it? Thank you in advance.
I use intact pods, no grinding. I start with about 400-450 ml water and put the pods in and boil low heat for 10 minutes. I leave the pods in to steep while it cools. With evaporative loss your final volume should be about 300ml for a single reel Nikkor tank.
Could you add a link to the list of polyphenol content? I don’t think that the author made these numbers…
I am curious what else is popping up after Rank 36…
BTW: made a paper development test with peppermint tea (from tea bags). Results didn’t have the darks as black as with caffenol-C. Maybe pappermint isn’t as potent as described in this list (rank #2!).
The origin of the polyphenols ranking table was sourced from European Journal of clinical nutrition (2010). Original article Identification of the 100 richest sources of polyphenols: an application of the Phenol Explorer database. I don’t advise their use as a paper developer, film only but feel free to experiment