Trying an alternative process for Kodachrome II

[marck mcgill]

Gentle Sirs, an american fellow and I are trying to cooperate and

find a way to develop old KII films (exposed in their days, I mean)

and recover the images to obtain a black and white (positive,

reversed) result.

 

He got some good results so far, but they seem to oscillate from

positive (reversed) to negative images on an unknown basis.

 

I am surprised of the lack of TECHNICAL information available on the

internet, about the KII film itself and the K12 original process.

Does anyone have any good link perhaps? Understanding the

peculiarities of the material we are working with would be a great

step already.

 

Did anyone tried some alternative process himself? On what was it

based? Even FAILURE reports are welcome, we are trying to collect as

much information as we can, and even a very basic one could be

something we're missing.

 

Thanks in advance, to whoever took the time to read this message as

well.

[steve_levine]

The "K" processes' were proprietary, and were never meant to be figured out.The color dyes are added during development, which is something you will never be able to accomplish at home.

[marck mcgill]

Yes. That's why we're working on a black and white reversal process.

[james_ogara1]

Marck wrote: Thanks in advance, to whoever took the time to read this message as well.

 

(music) Dreaming the impossible dream....

 

There was just in the past week an excellent thread on K-14 home processing.

[marck mcgill]

Yes, the one with Mr. Mowrey, very interesting. KII is different, though, and we can't seem to find information. If a user manual as that for K14 processing machines was available, that would be a great source indeed!

[david_martin2]

The folks at Rocky Mountain Film lab have a way to do it.

 

http://rockymountainfilm.com/k12slide.htm

 

Don't know if they'd be amenable to sharing their secret, though.

[marck mcgill]

Thanks, we know the men and we've been in contact. They are kind, though I don't know if they would share the secret either. However, their process leads to a NEGATIVE image, which is probably inintelligible since it's later scanned, digitally altered and finally recorded on VHS tape or dvd, which is the media you are supposed to look at. It's almost the contrary of what we want to do, unfortunately! Thanks for the input, anyway.

[robert_johnson15]

So you want the Kodak K-Lab K-14M manual(s), just go here:

 

http://www.kodak.com/global/en/service/Zmanuals/z50.shtml

 

You also want the theory guide? No problem, just check here:

 

http://wwwde.kodak.com/cluster/global/plugins/acrobat/en/service/kLab/tg2044_1_02mar99.pdf

 

Psst! FYI, I know where a K-lab machine is for sale at $46,000 if you are still interested! After reading the above, I didn't think so!

 

Robert Johnson

[randrew1]

I know something about the structure of the film and the process sequence, but what I'm writing here is speculation as I have never done this myself (nor witnessed it).

 

The easiest way to get positive images is to develop to a negative and then print onto paper or print film. If you want B&W slides, your best bet would be Eastman fine grain release positive film 5302. Check the processing instructions before you buy. You may have to go scrounging in Hollywood to find a short piece from a long roll of this motion picture print film.

 

If you want to process directly to slides, a B&W reversal process should be possible, but there are some things to watch out for.

 

I assume by now that you can deal with the rem jet backing.

 

If you are having trouble getting a consistent reversed image, you may be suffering from inadequate reversal exposure. They key is to get plenty of exposure from both sides of the film. The yellow filter layer has colliodal silver that turns into an opaque layer in the first developer. It is designed to protect the green and red layers from the blue light exposure in the K-12 process.

 

Good luck.

[marck mcgill]

@ Robert, thanks but I didn't express myself well. I meant that K14 manuals were linked in the other recent thread to which James was referring to, and I wish I had the K12 manuals instead...

 

@ Ron, I made a long story short in my first post because I couldn't figure this thread could be so much interesting for many people, but maybe now I can make it a little bit longer. We are seeking for a reversal process because - primarily - our goal are undeveloped cine films, double8mm primarily but Super8 as well. My opinion is that any support containing silver bromide from which is possible to obtain a negative image, can be reversed if processed accordingly. You understand, though, that a good knowledge of the support itself would be recommended. Please DO NOT assume that we know what to do with the rem jet backing, and go ahead. And please tell me how you would personally get rid of the yellow filter as well. Your help is appreciated!

[john_shriver]

Some of Ron's "film design" threads have noted that the yellow filters in color films are generally colloidal silver -- very fine silver particles. If you reversal process, when you bleach out the developed silver, they will go away as well.

 

The Z-50 manual has a good discussion on Rem-Jet.

[silent1]

Marck, if you're after a reversal positive, B&W, it should be pretty simple. Develop in a first developer (I've recently been told addition of some sodium thiocyanate helps with removal of the colloidal silver layer), bleach with a non-halogenating bleach such as potassium pemanganate or potassium dichromate in dilute sulfuric acid, expose or chemically fog, redevelop, and fix. There are stop and wash steps in there, of course, and many bleaches need a clearing bath in sodium sulfite solution to remove the stain from the bleach; the full sequence would be:<p>

 

First dev<br>

Stop<br>

Rinse<br>

Bleach<br>

Clearing bath<br>

Post-bleach wash<br>

Reversal (exposure or fogging bath)<br>

Reversal dev<br>

Stop<br>

Fix<br>

Wash<p>

 

Rinse before bleach is only an issue if you'll reuse the bleach; it's to prevent stop bath carry over. The bleach step should completely remove the colloidal silver filter layer, leaving you with a nice B&W positive. Clip tests, if you have enough film, will let you get the first dev time right -- it's the only critical part, as the remaining steps are carried to completion.<p>

 

Remjet often comes off and pours out with the first dev (it softens in alkaline solutions); if not, it can be rubbed off with cotton or saturated paper towel, rubbing only on the base side (which will be dull black where the remjet remains) after a soak in sodium carbonate or borax solution.<p>

 

FWIW, I've attempted to develop a single Bantam 828 roll of KII I found in a camera; I used Diafine, and got a huge amount of fog that I now gather was the colloidal silver layer; an attempt at bleaching with rapid fixer resulted in a very slight reduction in density, but nothing I'd call a real success; it may be that it's not possible to obtain negatives from KII without a more complex process (first thing I'd try if I had a lot of it would be using a C-41 color dev with black dye couplers added, followed by the rest of a C-41 bleach and fix process to remove all the silver and leave only the dye negative). Very short process may also give odd results as they may fail to penetrate evenly through the three smulsion layers and the filter layer.<p>

 

This process is of interest to me, as well, since it would parallel that necessary to obtain negatives from Fomapan R, a modern B&W reversal film with colloidal silver antihalation -- and which, in turn, is of interest because it's a readily available film precut in 16 mm width that could be used in my Minolta 16 cameras.

[reuben_c]

I have seen several references to black dye couplers. Where might one obtain them?

[silent1]

I've presumed there are such animals because of the number of B&W chromogenic films on the market. In fact, however, a quick Google suggests these films might simply use a balanced mixture of cyan, yellow, and magenta couplers to produce the B&W image. Microscopic examination of Ilford and Kodak B&W chromogenic films might reveal the existence of multiple dyes in the dye clouds, but it very well might not; the mixture might be on such a fine scale as to be inaccessible to light microscopes.

 

If black dye couplers exist as a separate chemical, I'd expect Rowland Mowrey to be the person here who'd know the name(s); I might also expect them to be available in bleach/redevelop dye amplification products, if such exist.

 

It should also be possible to produce a black-dye developer from the bleach/redevelop color toning kits I've seen sold, though at $20 for a kit it's outside my range for immediate experimentation; these contain a color developer with dye couplers already mixed in, and it should be possible to mix all three colors to produce a black developer, though I don't know if the concentrations would be high enough after mixing to produce a good black, or if only a gray would ensue. In any case, these color developer options would replace the second dev, but precede the bleach step in the order I outlined above; that is, you would first dev, stop, rinse, color dev, short stop (per C-41), and then bleach, wash, fix, stabilize, and wash -- in fact, the simplest way to apply all of this would be to run the first dev, stop, wash, and reversal exposure, then put the film into a C-41 process with the temperature reduced (and color dev time corrected to compensate -- plus color coupler modification to the color dev) to avoid damage to the K-II emulsion. Experimentation with the time and composition of the first dev would control final contrast etc. As an alternate, an E-6 process could be used, again with the coupler(s) added to the color dev step; this might be better, since IIRC E-6 requires lower temperature than C-41 and would be less prone to problems from reducing the temp to 70 F or so to pamper the softer gelatin.

 

Either way, the bleach and fix steps in these color processes would remove the silver antihalation just as well as the bleach step in a B&W reversal. It's hard to know which would be better without actually processing some old film...

[rowland_mowrey]

Guys;

 

Good couplers will cost you an arm and a leg, and a few other quite important body parts. They also come in lots that are more than you all could use in a lifetime.

 

There are less expensive alternative couplers, but all suffer from bad light or dark stability.

 

There is a 'black' or 'neutral' coupler, IIRC. I seem to have read about it somewhere attributed to Ilford. If I can locate a reference, I will post it.

 

I never really followed Kodak's chromogenic B&W film products, so I honestly cannot tell you how it is done. My opinion is that making a perfectly neutral dye from a mixture of 3 would be somewhat difficult due to the differences in reactivity. It is hard enough doing it in 3 layers (CMY), so I guess doing it in one might be harder. OTOH, I may be entirely wrong. I never even tried doing it nor have I talked to anyone who has done it.

 

I suspect that the best experts for the neutral coupler would be Dick Dickerson or Sylvia Zawadski.

 

I do believe that the bleach proposed above would remove the CLS yellow filter layer. However, one approach that I have heard of is to develop the film as a negative and then scan in through the yellow silver. I have heard that this will yield a quite usable B&W transparency. I have never done this myself.

 

Ron Mowrey

[reuben_c]

<i>It should also be possible to produce a black-dye developer from the bleach/redevelop color toning kits I've seen sold, though at $20 for a kit </i>

<p>

Do you know who sells these? I haven't heard of them before. Sounds interesting.

[rowland_mowrey]

As promised, I talked to the holder of the EK patent on chromogenic B&W film today. He told me that the EK patent issued before the Ilford patent.

 

He suggested that you might try resorcinol or a resorcinol derivative as a black coupler. They work just fine, are soluable in developers, and precipitate in gelatin after coupling with a color developer.

 

That was just a suggestion of the top of his head for you guys interested in chromogenic B&W.

 

I learn something new every day. I'm glad I was able to find the right friend to call so quickly.

 

Regards.

 

Ron Mowrey

[john_shriver]

Kodak publication AE-31 (Printing Color Films Developed as Black-and-White) has some relevant information.

[silent1]

Reuben, I've only read about them, but I have seen them advertised -- let me check Google. Okay, here you go...<p>

 

<a href="">Berg Color Toners</a><p>

 

These are dye-based toners that (I've read) work by bleaching, then redeveloping in what I take to be a color developer with dye couplers (their comment about mixing suggests it's not quite the same as adding couplers to CD-4 based color dev, though). A lot cheaper than I recalled, too -- might be worth trying with a Kodachrome II sample; for these, you might have to develop to a silver positive, then tone, but I expect if you follow through their instructions you'll see where you can intersect the B&W reversal and their dye processes to get a dye positive with all the silver bleached out.

[randrew1]

If I understand the details, you have Kodachrome II regular 8 movie film that you want to process to B&W positive for projection.

 

The rem-jet backing will be one problem. With still film it is possible to tape a roll to a clean hard surface and wash the backing off without getting the carbon black on the emulsion. (It is also possible to get lots of black globs all over your images. This method takes some practice.) This technique will be much harder with a 33 foot long roll of regular 8 movie film. (A "50 ft roll" of regular 8 film measures 16mm x 33 ft. After processing, the leader and trailer sections are cut off and the film is slit and spliced together. The result is 50 ft of film to project.) Movie film is normally handled in continuous processing machines where the film goes through a short dip in a high pH bath (developer is sometimes used) and then through a series of buffer rollers and sprays designed to carry the backing away from the film without contacting the emulsion. There is a description of the mechanism in this link:

 

http://www.kodak.com/US/plugins/acrobat/en/motion/support/processing/h242/h2402.pdf

 

I still think the folks at Rocky Mountain Film Lab are your best bet. They will provide a B&W negative and a video transfer. If you really want a positive film to project, you can find a motion picture lab to print the negative.

 

If you can manage these problems and still want to do this yourself, a standard B&W reversal process should work. The bleach in this process should remove the yellow filter. You may have to experiment with the developer times and the intensity of the re-exposure light. As mentioned before, it will be important to re-expose the film from both sides.

[olaf_labudda]

Maybe this link is helpful:

 

http://www.omniprints.com/super8/black&white.html

[olaf_labudda]

Perhaps this is interesting too:

 

http://lavender.fortunecity.com/lavender/569/k12bwnegdev.html