More on re-using Caffenol

Its been a while since the last post. I´ve been busy on other fronts, building a 6x17 camera out of a Cognac case for one thing. More on that later.

When it comes to Caffenol and using a batch for more than one 120 film. I´ve tried that out with success already. I´ve now done it again, this time three films in succession, all from the same 530ml mix, and this time not adding any instant coffee, just adjusting to the development times somewhat. I´ve not yet scanned the first film (not that relevant to the subject of re-using Caffenol really), but I have scanned both films two and three. How did they come out? Perfectly OK in fact. I wouldn´t say that I could see any detrimental effects of using the batch for three 120 films at all. In the case of 135 films, a single batch of 530ml could be used for up to 6 rolls if need be. The reason for doing this is not that one would save money, or the environment for that matter, but time. Time is a much more important commodity.

Adding 5-10% development time for Caffenol-C-M has been suggested as a place to start. I opted to add a minute for each successive film, even if the films were different and required different development times to begin with. For Acros (normally 12 minutes) 1 minute added would equate to nearly 10%, whereas a minute for TMX (normally 14-18 minutes) would equate to 6-7%. To be honest I think that both films are rather tolerant of variations in the mix and timings, that it doesn´t matter much. Don´t quote me on that though, YMMV.

From film no. 2 (TMX, EI 100, @ 16+1 minutes):

Flexaret Va, TMX, EI 100, in re-used Caffenol-C-M, @ 16+1min

Flexaret Va, TMX, EI 100, in re-used Caffenol-C-M, @ 16+1min

From film no. 3 (Acros 100, EI 100, @ 12+2 minutes):

Ikonta w/Novar f4.5, Acros EI 100 in re-re-used Caffenol-C-M @ 12+2min

Ikonta w/Novar f4.5, Acros EI 100 in re-re-used Caffenol-C-M @ 12+2min

Acros 100 Re-used Caffenol-C-M and night photography

Acros 100 saves time when doing night photography. Why? Because it has practically no reciprocity at all. For shots up to several minutes in length you can shoot as metered. See examples below.

Secondly, I´ve tried re-using Caffenol-C-M. I processed one 120 Acros 100 roll, and once out of the tank I developed yet another roll in the same soup. Caffenol is reputed to be one shot, however the active agents would seem not to be spent after just one film after all. Its not as if I couldn´t be bothered to mix another batch, I just wanted to try it out. Reinhold at the Caffenol.blogspot has met with success re-using Caffenol, and he´s the master of all things Caffenol, so why not? I added a teaspoon (5ml) of instant coffee to the mix, just in case and added a minute to the development, and adjusted nothing else. And hey presto, the negatives came out just as good as the first roll through the same mix. Same contrast levels, any differences could be attributed to variations in exposure as much as anything else.

I might continue doing this in future. Saves both time and effort.


The first three night shots. The last midday fog.

Flexaret Va, Acros 100, EI 200, 2 min metered and exposed, 13 min in Caffenol-C-M reused

Flexaret Va, Acros 100, 20 min exposure, pure guess metering, 13 min in Caffenol-C-M reused

Flexaret Va, Acros 100, EI 200, 2 min metered and exposed, 13 min in Caffenol-C-M reused

Flexaret Va, Acros 100, EI 200, 13 min in Caffenol-C-M reused

Acros 100 unintentionally overexposed by not one, not two, but most likely 5 or more stops!

My Kowa leaf shuttered 85mm lens developed a shutter issue at the exact same time I started testing Acros 100. At first I thought my very dense negatives were due to my getting the development all wrong, and subsequently went out and shot another roll. The second roll showing the exact same symptoms, even after changing EI from 100 to 200 and shaving 4 minutes of the development time. This is when I started suspecting other things, like my new light meter, and went out and shot another roll with the old meter. Still dense negatives bordering on opaque. I should of course have just studied the film borders and the film base to see if the development was off, or if it indeed was an exposure issue. But I panicked!

I finally cottoned on to the party to blame, the lens´leaf shutter was sticking, on all speeds. It didn´t really matter which speed was set, the time it took for the shutter to close was at least a couple of seconds, and sometimes it didn´t close at all. I managed to get my flatbed scanner to interpret a few frames out of three rolls of negatives, barely. I suspect that a better scanner would have been able to salvage something from most of them, and that wet printing could get nice results. But alas, I´ve not a $1000 scanner, nor is my darkroom ready yet.

To wrap up the winging, I´d like to say that I´m impressed with what Acros can tolerate of overexposure. Because these negatives got their fair dose of it. Reinhold rates Acros to an EI of 200 in Caffenol-C-M. These negative probably got exposed in single digit EI´s. The results being big chunky grain in the lighter (most overexposed areas) and still quite nice and fine grain in the darker areas. There´s even some quite nice midtones evident on most of the negatives in question. I now know that not only does Acros push well, it pulls well too. Not that I´d want to pull 5 or more stops out of a fine grained film, at least I know there´s a lot of exposure latitude on hand with this film.

A couple of examples:

The two tallest buildings in Oslo. EI 1 to 5, Acros 100, Caffenol-C-M 12min @ 20C

Self portrait. In shadow, so EI probably 5-10 somewhere,Acros 100, Caffenol-C-M 12min @ 20C

In fact I rather like the first picture, the gritty look is becoming and suits the subject material. I´ll be printing this one once I´ve got a darkroom going.

Acros 100, the long route

I´ve been trying to test Acros 100 for ages now. But for some reason a compound of non-related issues has prevented me from doing so. First my Mac decided to have a disk crash, so scanning any negatives was a no go. Then the camera that I´ve come to rely on felt it needed a hiatus, the shutter giving in. First intermittently, then more or less all the time; ruining three rolls of Acros in the process.

Finally though I´ve been able to both expose, develop and scan enough Acros negatives for form an opinion. It rocks! Its even more fine grained than TMX, though I think I still might prefer TMX midtones. Its pushes very well, but funnily enough it pulls even better. I know, since the shutter stuck I have a host of negatives overexposed by at least 5 stops, probably more. Boy are they dense, but some are scannable on my lowly Epson V500, resulting in very heavy grained images - but not without some merit. More on that later.

Acros 100, rated at EI 200 for the most part. Developed in Caffenol-C-M (C-H without the bromide remember) for 12 minutes @ 20C.

Acros 100, EI200, C-C-M 12min @ 20C, taken with Flexaret Vb

Acros 100, EI200, C-C-M 12min @ 20C, taken with Flexaret Vb

Acros 100, EI200, C-C-M 12min @ 20C, taken with Kowa Super 66

I´ve also tested EI 50-80 and up to 15 minutes @ 20C, and they work just as well. Acros is almost as robust as TMX when it comes to exposure and development latitude.

New old brew

I´ve now used up all of 6 litres of developer, 12 films in all. I had to pour out some moldy coffee, but apart from that I used every drop I pre-mixed in the beginning of October. I´ve brewed up new solutions for this the latest TMAX100 film (examples below). I´ve dispensed with Potassium Bromide altogether. Whether or not that was a good idea I´m not sure. For the first time I´ve got what could be streaks, 2-3mm along one of the edges of most of the frames. I´m not sure why. Anyhow, when mixing the new Ascorbic acid and Sodium Carbonate solutions together, before adding coffee, I could see a marked difference in colour. The stored solutions grew ever more yellow when mixed, the freshly mixed solution however turned a very pale greenish yellow. Whether or not this change in reaction has anything to do with the developing capabilities I couldn´t say. I seem to be getting good results no matter how long the mixtures have been stored.

Fresh Caffenol-C-M (no PB remember):

TMAX100, Caffenol-C-M

TMAX100, Caffenol-C-M (if you pick one to enlarge, this is it)

TMAX100, Caffenol-C-M

TMAX100, Caffenol-C-M

Caffenol-C-H, almost C-M

On Reinhold´s recommendation I´ve been slowly, but surely, making my way from C-H to C-M Caffenol for TMAX100. The difference being potassium bromide, or the lack of it with respect to Caffenol-C-M. This is the last film of TMAX100 with any PB at all, 0.2g/l to be precise. Its also the last film from the old batch of chemicals, but with fresh coffee.

TMAX100, modified C-C-H

TMAX100, modified C-C-H

TMAX100, modified C-C-H

More of storage of Caffenol pre-diluted components

As you know, I dilute each of the three main ingredients at 3x strength and store in stand bottles. It works too, at least for something in the region of 6 weeks. I´ve a hypothesis that the sodium carbonate and the ascorbic acid will keep very well. I can´t see why the first should go off, and the second is often used as a preservative. But the coffee, it will go off sooner or later. I therefore performed a test to see how well the coffee mixture will perform at the end of its useable lifespan. At six or seven weeks it starts to develop mould. I would suspect that in the warm summer this can be shortened by a couple of weeks or more. I developed two films the same evening. Both films developed in developer mixed from the same well matured sodium carbonate and ascorbic acid mixes, but one with the old coffee mixture, and one from a fresh batch of coffee. I used 18 minutes for the old coffee mix, and 16 for the new, both @ 20C/68F. I´ll jump the gun and reveal that I couldn´t quite see much of a difference. Judging from the film edges and the Kodak markings both films were developed to within a hair´s breadth of each other. Meaning that the old coffee most likely had deteriorated somewhat, it had been developed an additional two minutes, but not so much as to have an impact on the end result. Both films were equally easy to scan, I would hesitate a guess that they would perform well when subjected to darkroom enlarging.

A few examples from each film.

TMAX100: Old coffee, as are the other chemicals

TMAX100: New coffee, otherwise "old" chemicals

TMAX100: Old coffee, as are the other chemicals

TMAX100: New coffee, otherwise "old" chemicals

TMAX100: New coffee, otherwise "old" chemicals

I´ll be using the rest of the now 9 week old sodium carbonate and ascorbic acid solutions until empty. I find no reason not to. The coffee mix will most likely keep for a good 6 weeks.

Oh, and I´ve just ordered some Fuji Acros 100, it´ll be fun to see if it performs as well as Reinhold at the Caffenol.blogspot says, and if it compares to my TMAX100 experiences.

Note: All pictures taken with my Kowa Super 66