C-22 in Rodinal, or in ECN-2

shead · May 23, 2023

I have the odd roll of found film lying around, C-22 Kodacolor-X. I'd liek to see if I can pull any images off it but the C-22 process is dead. I read that this color film can be processed in BW chemistry for a monochrome image. I use Rodinal, and a search turned up someone a decade ago did 54 minutes at 1:100 dilution, should I assume that is stand development? Anyone have a better mix/time suggestion?

Secondly, I have a couple of ECN-2 chemistry kits and read that this process has the CD-3 in the developer that the C-22 process has (while C-41 uses CD-4). If that is the case (I'm not sure it is) why wouldn't ECN-2 development gives at least some images?

Thanks!

Rudeofus · May 23, 2023

One thing you have to keep in mind: C-22 process will not survive the 38°C you have in C-41 process,and even less the 41°C you have in ECN-2 process. So whatever you do, you have to translate the process to 24°C/75°F by extending dev times. Not sure, whether the time/temp calculator provided by Massive Dev Chart will cover such a large temperature shift correctly, but it could give you starting numbers.

Another thing is the color couplers used in C-22: these require Benzyl Alcohol in the color developer to make them accessible to the color developer, see the recipe posted in this thread. If you compare this formula to ECN-2, you also see, that the C-22 CD (pH 10.7) is quite a bit more alkaline than ECN-2 CD (pH 10.25), and it also contains a bit more CD-3 (5 g/l vs. 4 g/l).

So a modified ECN-2 CD would use a bit higher concentration, raise pH to 10.7 and add 5ml/l Benzyl Alcohol, then it could be used in regular C-22 process. Colors will be off, but that's already the case given the film's old age.

Since you have "the odd roll" of this film, you might be safer with Rodinal treatment. If you later decide "damn I really want these colors", you can always bleach back and the use color development to completion, e.g. with an E-6 color developer, or thorough development with regular ECN-2.

foc · May 24, 2023

I have read about people developing C22 and Agfa CNS in C41 BUT at 20c. Otherwise, the normal 38C will melt the emulsion.

Developer at 20C for 20 mins. and then bleach for 13 mins and fix for 13 mins (all at 20C)

I know the C41 developer is different from C22 but it could be worth a try.

You could also just develop it as B&W.

dabsond · May 24, 2023

Talk about timely, I just acquired an old Kodak with the same exposed film type. All I have on hand for black and white is HC110. Any thoughts on this combination?

shead · May 24, 2023

Thanks everyone. I think I'll just go the Rodinal direction. I'm not sure there are even images on this as it wasn't stored very well.

foc · May 24, 2023

shead said:
Thanks everyone. I think I'll just go the Rodinal direction. I'm not sure there are even images on this as it wasn't stored very well.

Can you let us know how you get on, please? Maybe even post an image or two.

Romanko · May 24, 2023

Troy Walters (@typicalaussiebloke) did a lot of experiments with C-22 film development. Here are a few links:

C-41 processing early 1950s Kodak Kodacolor films

G'day all. I've recently been shooting unused vintage colour films from the 40s, 50s and 60s and have been cold developing them with my Tetenal C-41 colour kit and have had mixed success, the best result I got was 1958 expired Kodak Ektachrome 120...

www.photrio.com

Shooting/processing vintage 40s-60s era Kodak colour film: Part 1 Kodacolor

Over the past 8 months I’ve been hooked on shooting vintage Kodak colour films from the 1940s, 1950s and 1960s as I’ve discovered through some peoples photos on Flickr like this (1962 K…

expiredfilmphotographer.wordpress.com

Shooting/processing vintage 40s-60s era Kodak colour film: Part 3 Ektacolor

This is the 3rd and final part of the vintage Kodak colour series which is on 1960s era Ektacolor film. Ektacolor film is a colour negative film just like Kodacolor and was also processed in C-22 w…

expiredfilmphotographer.wordpress.com

I tried cold C-41 on several rolls of "mystery" film. It worked to a certain extent. I got pictures and I got colours.

Romanko · May 24, 2023

Rudeofus said:
If you compare this formula to ECN-2, you also see, that the C-22 CD (pH 10.7) is quite a bit more alkaline than ECN-2 CD (pH 10.25), and it also contains a bit more CD-3 (5 g/l vs. 4 g/l).

So, presumably C-22 CD is more active than ECN-2. This makes sense since it worked at a lower temperature. Would it be possible to compensate for lower PH of ECN-2 and lower CD-3 concentration by extending the development time?

Rudeofus · May 25, 2023

Romanko said:
So, presumably C-22 CD is more active than ECN-2. This makes sense since it worked at a lower temperature. Would it be possible to compensate for lower PH of ECN-2 and lower CD-3 concentration by extending the development time?

The biggest problem with the situation I see right now is, that it would require quite a bit of experimentation to find out. Yes, of course you can develop longer to compensate for less active developer, but by how much?

Someone on photrio once plotted an H&D graph of "stand development in dilute Rodinal". Everyone assumed, that this type of development would provide great shadow detail and somewhat suppressed highlights, when in fact it was shown to me more or less "gamma max" development, i.e. all the developable silver was developed. Given the likely age of this C-22 emulsion and its likely loss of sensitivity and contrast, that kind of "gamma max" development may actually the way to go. Take a small test clip, develop the heck out of it in ECN-2 CD plus 5 ml/l Benzyl Alcohol and check fogging. If it is heavily fogged, add 2 g/l KBr to the developer and try with the next test clip. If fog is shown to be low, develop the rest of the film roll with this soup and be done with it.

The result will need a lot of tweaking after scans have been made, but there should be visible results.

Romanko · May 25, 2023

Rudeofus said:
Given the likely age of this C-22 emulsion and its likely loss of sensitivity and contrast, that kind of "gamma max" development may actually the way to go.

I can't find this thread, but someone here experimented with developing old Kodak Verichrome film. They did snip tests for both unexposed (base fog density) and fully exposed (maximum density) as a function of development time. From memory there was an optimum time for maximum (Dmax - Dbase). I wonder if this time was to just achieve "gamma max", a point where you are not getting any more Dmax increase and the fog starts increasing.

Rudeofus · May 26, 2023

Romanko said:
I can't find this thread, but someone here experimented with developing old Kodak Verichrome film. They did snip tests for both unexposed (base fog density) and fully exposed (maximum density) as a function of development time. From memory there was an optimum time for maximum (Dmax - Dbase). I wonder if this time was to just achieve "gamma max", a point where you are not getting any more Dmax increase and the fog starts increasing.

There's a distinct chance, that fog will start growing long before good highlight densities are reached. This is especially likely with very long expired and poorly stored film stock. This is the point, where extra restrainer comes in handy. BTW David Lyga has posted great insights into beating old, expired photographic material back into shape, these could well serve as starting point for adjusting development of this old C-22 roll.

Romanko · May 26, 2023

Rudeofus said:
There's a distinct chance, that fog will start growing long before good highlight densities are reached

This is something I would like to experiment with. I expect the hightlights to start developing first no matter if the film is fresh or fogged but I don't have enough experience or theoretical knowledge to support my intuition.

Rudeofus said:
David Lyga has posted great insights into beating old, expired photographic material back into shape

Here is David's thread:

How to deal with varying amounts of age-fog in B&W films (and papers)

I received a query from a subscriber concerning how to process age-fogged films. One need not have to deal with printing through this morass of density, Instead, David Lyga (in his never-ending 'experimentation voyage') has truly saved the day. My methods are decidedly unorthodox, but they do...

www.photrio.com

There's also a great post by Daniel Keating:
https://www.diyphotography.net/how-i-removed-base-fog-from-old-film-stocks/

shead · May 26, 2023

foc said:
Can you let us know how you get on, please? Maybe even post an image or two.

I will indeed. If I get any pics I'll notify this thread.

Romanko · May 28, 2023

In this video Kodacolor-X was developed in D-76 for 13.5 min at 70F/21C.
The negatives were very dense (overdeveloped?) but the images were recognizable.

real_liiva · Jun 12, 2023

I personally haven't tried to resurrect any c-22 film but i have tried orwocolor. Not sure, but i think the process may have been based off of c-22 or maybe something even a bit older (despite the film still being made and used up to the 90s). I tried a bunch of different exposures and development techniques in c-41 developer but got the best results with about 8 minutes of development at 24c while exposing the film around iso 3 (originally 64 iso). Also obviously the color couplers in the film didnt like cd4 as a few times when i bleach bypassed the film the image in the silver was much stronger than the image in the dyes. Also interestingly the emulsion didnt disintegrate at 38c but unfortunately processing it identically as c41 film resulted in an extremely heavy base fog with the blue channel completely gone and barely anything red or green. I guess maybe the later batches could take the higher temperatures, these in particular expired in 1987 afaik.

C-22 in Rodinal, or in ECN-2

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