Caffenol -- an experiment, and why I'll look elsewhere

Caffenol is a developer just as any ordinary developer, To get repeatable results you definitely need to be exact, that is WHY we're having this discussion, noone is having a similar discussion over Kodak D76, guess why?

I agree, you dont NEED photo grade anything, as long as you stay with the same bottle anything, but as soon as something changes, everything MIGHT change, that is why w're having this discussion, people gets puzzled over it, and that is why somebody's have to poit it out, its obvious.

OK cosequences was maybe an overstatement, we're not talking "final solution" here!

I use non-photo grade components myself, but stick with the same brands and measure out EXACTLY, so I don't suffer consequences!
I plnat to upgrade to photo grade though, my vitamin C is better, it is medicine grade.

Gerald C Koch said:

The aroma of coffee is caused by several sulfur compounds called mercaptans or thiols. Unfortunately for photographers these same compounds are also very active fogging agents. No wonder that people are experiencing high fog levels with coffee developers. These developers are a parlor trick and nothing more.

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I'm going to switch from cofee to Hydroquinone, keeping the Vit C since its a well known fin grain developer, and Im searching for a source of caffeic acid in its pure form just out of interest.

Erik Prestmo said:

I'm going to switch from cofee to Hydroquinone, keeping the Vit C since its a well known fin grain developer

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Ignoring certain special applications, developers must contain a primary developing agent and perhaps an additional secondary developing agent. Both hydroquine and ascorbic acid are secondary developing agents. You will need something like metol or phenidone as a primary agent.

Whiteymorange said:

Have you tried printing one of the negatives? When I first tried coffee developers I was aghast at the miserable looking negatives - they scanned horribly and looked barely printable.

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I have only tried Caffenol once and I had the complete opposite experience. My negatives looked just as good as they would have done if I had used Ilfosol S which was my standard developer at the time.


Steve.

Generally negatives looked overdeveloped (i.e. I should have upped the ISO and exposed accordingly!) and with a pronounced fog, following sloppy advice initially (spooful of this and a spplash of that), Using less soda (effectively lowering the PH, and hence the activity of the developer) should lower the ISO and give me more corrct developed negatives, and KBr shold control the fog.

That said fog is no catastrophe, it just reduces contrast and might be something you want if you "press" films.....

However its too early to tell, I feel we need to experiment considerably, to zoom in on a lower soda concentration, too close to PH7 and the concoction might be totally uncontrollble, or might not work at all, as some users have reported.

Another thing is controlling the cofee. Quite clearly very many don't understan that they need to use the same coffe from film to film. And one needs to find coffe that is *right*. Dark rich and bitter brands are what we are after. Happily these brands are cheaper also and quite often found in work environments, where penny-pinchersa tries to buy cheap on our behalf! It might be a very samll crime indeed to liberate a can or two, saving the coworkers health!

It seems to me that the best choice of instant coffee would be the very cheapest brand since it would have the least aroma and thus produce the least amount of fog. Someone willing to do a test?

That is exactly what I've been doing, I searched out a from-china-durn-cheap-store (seems they are vereywhere in he wesatern world by now) and got their cheapest darkest-looking brand that was additionally branded "brasero".

You get fog nonetheless, but probably less of the oils and fats that cropped up as a problem with others, seems I have little problems with the streaking reported elsewhere. When my chemist supplies the KBr I've ordered, the fog WILL be gone!

Gerald C Koch said:

It seems to me that the best choice of instant coffee would be the very cheapest brand since it would have the least aroma and thus produce the least amount of fog. Someone willing to do a test?

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I'm not sure this is right. It's more likely that cheap coffee will have a *worse* aroma---the "skunks and rubber" thiols rather than the "mmm, coffee" ones---than that it will be across-the-board less aromatic.

While I can't prove this, I bet there's a lot of variation in flavour chemicals between batches of nominally "the same" coffee, at levels that could be photographically significant without being culinarily significant. (Especially since the cheapest coffees are likely to have mixed origins anyway: whatever was going cheap at the wholesale auction that month.)

-NT

Over the years, during times of tight finances, I have tried many cheap brands of instant coffee they all tend to be pretty tasteless with little or no aroma.

"el gringo" purchased at the le clerc in ile-sur-le-doubs
worked better than any rotgut i had the privilege of purchasing locally.

Gerald C Koch said:

Ignoring certain special applications, developers must contain a primary developing agent and perhaps an additional secondary developing agent. Both hydroquine and ascorbic acid are secondary developing agents. You will need something like metol or phenidone as a primary agent.

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Where you have THAT from?

Metol and Phenidone are chosen because they are more active, works faster and gives a denser negative.

There are no such thing as primary and secondary developing agents.

Either you have developing agents or nothing.

Both Ansco and Kodak published developers based on alkalis with hydroquinone as the single developing agent. They also had glycine developers.

Based on a quick look in "Wissenshafltliches und Angewandte photographie, band V, Die technik der Negativ und Positivverfaren", Springer Verlag 1955, you know little about what you try to sound knowledgeable of.

And Lowe made developers with compounds that accelerated the activity of glycin. I used Edwal 12 for a year, and it's a glorious developer.

If a developer works, it works. If the prints look great, they look great. You can't argue with that. That is EVIDENCE that it works well. The rest is academic.

Have fun making pictures!

SNIP

Gerald C Koch said:

These developers are a parlor trick and nothing more.

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Gerald C Koch said:

It seems to me that the best choice of instant coffee would be the very cheapest brand since it would have the least aroma and thus produce the least amount of fog. Someone willing to do a test?

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i thought it was a parlor trick ... ??

Erik Prestmo said:

Where you have THAT from?
...
Based on a quick look in "Wissenshafltliches und Angewandte photographie, band V, Die technik der Negativ und Positivverfaren", Springer Verlag 1955, you know little about what you try to sound knowledgeable of.

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With all due respect, instead of criticizing someone else perhaps it would be better if you actually read the book you cite! Better still read Grant Haist's more recent, massive two volume set "Modern Photographic Processing." Until then there is no point in discussing things further.

Trask said:

I recently tried Caffenol ( 27 g sodium carbonate + 8 gr ascorbic acid + 20 gr Folgers in 500 CC water) to develop a roll of Tmax 100 and found that it worked pretty well, though base fog was high -- the sign, I read somewhere, that perhaps the mix is too alkaline. I did notice that one side of some of the photographs (120 film in a Hasselblad 500C) was a bit lighter than the other, as some have noted on the internet.

So I decided to try a less active version of 10g carbonate + 2g ascorbic + 10g coffee in 500ml water. I split the mixing into two portions of 250 ml each, adding first the carbonate and then the ascorbic acid to one beaker, and the coffee to the other 250ml of water. I wanted to be very sure that the coffee was fully dissolved. I added the coffee mixture to the other beaker and stirred it fully. I then added 5ml of a solution made by dissolving 10g of salt in 100 ml water, the idea being that this would reduce fog while also extending developing time.

I developed a roll of 120 TMAX 100 in this mixture for 28 minutes, agitation on the minute, and was generally disappointed -- now both edges of the length of the film was overdeveloped (leading to brighter stripes along the side of each image when scanned). I come away with the impression that Caffenol does not agitate in a small tank as readily as other developers. Perhaps the best method is to use a rod to lift spiral reels in and out to agitate and transfer from bath to bath. I also wonder if the oils seems floating on the surface of the developer could be a culprit -- could the oils attach to the surface of the film and remain in place to a greater extent in the middle portion of the roll of film than at the edges where agitation move the developer around more? I had the idea of getting one of those measuring cups used when making gravy that have a tubular spout that runs all the way to the bottom of the cup, so that fats will rise to the surface and will not be poured into the gravy because the spout draws from the sauce at the bottom.

Perhaps one technique would be constant agitation. But while I find that Caffenol can produce some nice images as scanned through the fog, there are other developers that do not have this edge development problem and produce images that are just as attractive. If others have found a solution for the edge development problem, I'm certainly interested in hearing it.

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getting back to the original post ...
not that the sci-tech conversation wasn't interesting ... :rolleyes:

trask ...
have you tried a different coffee ?
i have never used folgers, just the cheapest
stuff my local stop and shop sells.
while i joked about the flavor crystals mrs. olson
used to advertise as a selling point for folgers ..
it might be the reason (coupled with it being a darker roast )
you are getting oils in your developer.
cheap (cinnamon roast) instant works great
dark roasted coffee can have more oils cinnamon roast
is dry compared to a dark roasted coffee.

try making your developer the way whitey suggests ..
instead of exact measurements in grams, use table and teaspoons ...

I just (today) packed up all my photo and darkroom gear to send it by sea freight from here in Saudi Arabia to Virginia, which means no activity for me for about three months. You can bet I'll be trying new variants once I can.

BTW, I wonder what would happen if you actually brewed up a cup of hot instant coffee, and then let it cool down to processing temperature? Perhaps the use of boiling water would improve the coffee's dissolving, and make a more cohesive "mixture" -- having gotten through college finals in 1972 by drinking instant coffee made from "hot" tap water, I can attest that most instant coffees don't really blend well at less that boiling temps.

I am never sure where to jump into this thread; there are so many separate strands developing!

Let's see... first of all Trask, have a safe journey! I look forward to discussing further coffee experiments with you when you are settled in again and can get back into film development. Hopefully someone else who is having the edge development problem will give the vigorous agitation idea a try and let us know if it works for them too.

The idea of first brewing the coffee before making the developer is an interesting idea that I always wondered about too. Frankly, I often see oil floating in cheap coffee even after brewing so I am not sure how much mixing effect occurs, but still it would be worth a try! The presence of an oil or any kind of "separation" could be the culprit responsible for edge over-development. Along those lines, another idea I came up with was to add a drop of photoflo to the developer - the idea being that it would act as an emulsifying agent and stabilize the mixture. I am probably "speaking out my a**" (as my wife likes to say ), since I don't know if emulsifying is even the right term here. But the idea seems plausible at least. So again, maybe another thing that could be tried.

Oh, and that reminds me - I have been using a water rinse in place of a stop bath; and I wondered if that might be part the problem. My way of doing this rinse was basically the fill and dump method - just like the Ilford method for washing the fix away. It occurred to me that if the developer was somehow sticking more tenaciously to the edges of the film, then my rinsing technique could definitely be the source of the problem. I mean, just think of how many extra minutes of development could be going on if the water rinse wasn't really washing away the developer fully. Well to make a long story short, I did a test. I developed one roll of film using vigorous agitation for the water "stop" stage only, but not for development. What I found was the edges were as bad as ever. So apparently, the development stage is key, and the vigorous agitation is really most important there.

Another thing - until jnanian pointed it out, I had missed that you were using Folgers - just like me. Hmmm... I guess two cases doesn't really make a pattern, but I wonder how many other people having the overdeveloped edges happen to be using this same brand of gut rot? Is anyone using a different brand and seeing the problem? As for the choice of brands... my reasoning for choosing Folgers Instant was precisely for the sake of consistency. My understanding was that the instant used the lower quality beans (the ones better for developing), and that as the leading brand - at least I think it is here in the States - the Folgers would be the most likely to be consistent from jar to jar, and from year to year. Having said that I don't know how true it is since I haven't tried any other coffees. But it seemed like a reasonable strategy.

Finally, I have to say something about consistency. After dozens of rolls developed in caffenol-C, even after varying the recipe a bit, my results have always been very consistent, and predictable once I settled on a particular formula. Heck, even the edge problems that are the topic of this thread were always consistently present (until I found a solution that is)! So I would suggest that except for the possibly of slight variations in a manufacturer's coffee mixture over time, there is no reason that coffee-based developers can't be as consistent as any other kind of developer. Sure, you get people reporting complete failures or particular problems. But I think most of those are probably due to some oversight - such as getting the recipe wrong, using baking soda instead of washing soda, letting it sit too long before using, those kinds of things. And mistakes like that can happen with any developer the first time someone uses it, especially if they are new to developing in general. So I wouldn't take those kind of reports as any indication that coffee is somehow inconsistent, or undependable as a developer.

Denverdad said:

Another thing - until jnanian pointed it out, I had missed that you were using Folgers - just like me. Hmmm... I guess two cases doesn't really make a pattern, but I wonder how many other people having the overdeveloped edges happen to be using this same brand of gut rot?

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I am, for the simple reason that the source I took the recipe from called it out by name and I figured levels of caffeic acid (and whatever other chemicals are involved) might vary from brand to brand.

If the oils are contributing to the overdeveloped edges, I wonder if some kind of filtration would help. Regular coffee filters will pull out some of the oils---it might be worth a try.

-NT

Another thought: many years ago I used a coffee filter unit that operated thus: it was a large plastic container that had a depression in the bottom where a 1/2 inch thick reusable filter was fitted, and below the filter was a hole that you plugged with a rubber stopper. You would pour in a pound of ground coffee, then add 1 or 2 quarts of water -- I can't remember exactly -- and let it sit for 24 hours. Pull the stopper and let the coffee "liqueur" run out over 20 or 25 minutes. The idea was that you'd put an ounce or two in a cup and add boiling water to create a cup of coffee that was tasty because it did not have the acidity found in brewed coffee. So perhaps the same process could work for developing. Of course you could just dump a pound of coffee in a quart of water and let it sit, but you'd have to work through how to filter the liqueur thereafter. Hey, here's a website on the process I described: http://www.toddycafe.com/ If this worked, you could have a cold bottle of brewed coffee liqueur sitting available as the basis for a developer.

ntenny said:

If the oils are contributing to the overdeveloped edges, I wonder if some kind of filtration would help. Regular coffee filters will pull out some of the oils---it might be worth a try.

-NT

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I actually do strain the developer through a coffee filter just before using it. I have been doing that since the beginning as a "just-in-case" measure, thinking that there might be undissolved particles. Honestly though, I can't say that I have ever seen anything caught by the filter, so I am not sure if it is really needed. Someday I am going to have to test whether steps like that are really necessary, and see if I can streamline the process a little.

Hi guys,

I was "out of order" for a few days, then the board was, and now I read this topic. I'm pleased that interest in Caffenol-C is still big and my blog is quoted several times. I didn't expect this attention when I started.

This is a great topic with lots of important aspects.

First some thoughts about scanning vs. darkroom prints: Concerning grayscale you can capture much(!) more information with a scanner than on a print. Even with a modest scanner like my Canoscan 8800F. So uneven development will be much more visible when scanning. Implied you use a good scanning program and know how to use it. No point of discussion anymore for me. Concerning sharpness every modest enlarger/lens outperforms any affordable scanner hands down. Implied you know how to use your enlarger. No point of discussion anymore for me. Feel free to disagree of course.

I had only very few to no probs with uneven development until now. I made some experiments with low pH-Caffenol-C to improve grainyness and fog. I did get usable but still improvable results. Because developing time will be probably longer than with "regular" Caffenol-C, I decided to give stand development a try. The results were interesting. More fog, lower film speed, some smaller grain, but massive uneven development. See the comparison here:

http://img233.imagevenue.com/img.php?image=36614_teststandvsagit_122_58lo.jpg

APX 100: low pH stand development vs. Caffenol-C-M standard agitation as described in my blog.

I made no proper blackpoint adjustments to make the differences more obvious. I thought before that agitation probably might be the key to even development and I have the feeling that low pH increases the problem.

The uneven development is caused by bromide streaks. Bromide coming out of the emulsion sinks down and inhibits the development. Important: the shown sample pic is upside down! Where the sprocket holes are, the bromide stream is interrupted and we find more development below the holes. Finally the bromide accumulates at the bottom of the tank and there we find the least development. You can also see less development below parts of the neg that are heavy exposed. More bromide is set free there, sinks down and inhibits development.

I'm sure this is the explanation for the phenomenon. Agitation helps. I have good experiance with the fast Xtol-like agitation regime, 5 fast tilts in 5 seconds, every 30 seconds, like given in the Xtol datasheet. That is obligatory for Xtol, and Caffenol-C behaves quite similar in many ways.

It also explains why different films behave different. Old style emulsions contain more bromide, newer ones more jodide. That also explains different experiances. The APX 100 seems to be very sensitive. Adding potassium bromide may help, if bromide is present from the beginning in a good amount the effect may be decreased, but also film speed. So agitation is the key. If you encounter uneven development, agitate more. Modern emulsions like TMax, Delta or Acros are much less sensitve and show less fog with coffee developers.

Btw, the biggest problems seems to be with large format sheet films as far as I read here and elsewhere. No miracle as you can't turn the sheet container upside down?

Fog is not the major problem, it's the agitation - imho. Thank you guys for thinking about this. Waiting unpatiently for your comments.

Cheers from Heidelberg/Germany - Reinhold aka grommi aka imagesfrugales :-D

PS: in the meanwhile, when the board was closed, I published the recipe for a low-pH, low grain, low fog Caffenol-C-L, suitable for (semi-)stand development, see my blog.

The imagevenue link made a porn popup for me, so NSFW warning.

I'm too impatient to do stand developing.

I have had no problems developing 8x10 fomapan100 in caffenol-C in a 8x10 tray with 1L of developer. No unique uneven development. I rock the tray about every 30s and flip the sheet of film over twice quickly so it's back face up every 2 minutes. I can do 2 8x10's with 1L of developer. I've done 3, but the third comes out somewhat weak; scannable for sure. I might try longer time for the third sheet next time.

I have developed 4x5 Efke50 in a combinplan tank with caffenol-C as well and that works well and even. That is something you can agitate by inverting, rocking, spinning, anything you want. I slowly invert it. Too violent and the film can pop out of the slots with the sloshing. you can still do plenty of agitation without being violent with it.

Next for me to test is the paterson style 4x5 reel from mod_photographic.

I would agree that if you are experiencing uneven development - especially the overdeveloped edges situation - agitation is the key. But as I reported earlier, just agitating more (i.e., for longer durations) did not help, even all the way up to continuous agitation for the entire development duration. For whatever reason this developer seems to require more agressive agitation, not just more agitation to get a uniform result. At least that has been my experience, which has involved daylight tank development of roll film only, my particular recipe/ingredients, the particular films I have used, and so forth. So consider those qualifications in my remarks. But if I were going to try stand or semi-stand development I think I would be inclined to keep my agitation durations the same, but use a more vigorous agitation technique for those durations.

Denverdad, can you show somehow a sample picture for the overdeveloped edges? For me it's always difficult to make up my mind by describing a phenomenon.

Without a restraining agent I see overdeveloped (not restrained) lines along the borders of the film, where it is covered by the reel. Thr 2 millimeters, that are never visible in the image. That the whole neg area is affected I only saw with stand development.

It's simply a bromide thing, I have no doubt. The bromide comes out of the emulsion during development and must be spread by agitation. Or you add the bromide as a seperate agent from the beginning, then much less or maybe no agitation is needed for even and low-fog development.

Unfortunately I can't verify your rigid agitation method, since I have perfect results already with standard agitation. But stand development without bromide clearly showed, that agitation is very important when not using a restrainer.

BTW, since longer I use demineralized water only for diluting, we have very calcinated tap water that also varies from day to day. Soda and coffee solute much better without clumps. And I feel better regarding my approch of accuracy where possible.

Cheers - Reinhold

grommi said:

Denverdad, can you show somehow a sample picture for the overdeveloped edges? For me it's always difficult to make up my mind by describing a phenomenon.

Without a restraining agent I see overdeveloped (not restrained) lines along the borders of the film, where it is covered by the reel. Thr 2 millimeters, that are never visible in the image. That the whole neg area is affected I only saw with stand development.

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Reinhold,

Sure. The sample below should give you a better idea. It is a snapshot of a two-frame strip sitting on my light table. The difference between center and edge is easiest to see in the gap between the two frames. I wasn't sure if the effect was easier to see as a positive or negative, so I included both versions.

The potential difference between tap and distilled water is an interesting point. I am in the habit of always mixing chemicals with distilled water (although I typically rinse with tap water).