Using ancient Kodak C-22 kit
Some time ago I bought an old Kodak C-22 processing kit,the 1 pint size. Intent is to use it to redevelop a roll of C-22 I took 45 years ago and processed some years ago as B&W. I read in Kodak Publication AE-31 that you can just bleach the film in fresh E-6 bleach, re-expose the silver halides, and process as color.
So the first question is whether the chemistry in the C-22 kit has any chance of being good.
Will part A of the developer (contains 4-amino-N-ethyl-N-(β-methane sulfonamido-ethyl)-m-toluidine sesquisulfate monohydrate) still be good? (I presume this is a form of CD-3.)
Will part C of the developer (contains benzyl alcohol) still be good? That bottle is still liquid.
The bottle of part B of the hardener appears to contain a brown powder at this time, the caution label says it contained formaldehyde and methanol. Has that gone bad?
The next question is what parts of the process need to use C-22 chemistry? Obviously the developer. I presume I can use any stop bath. Do I need to use that C-22 hardener, or would Flexicolor Stabilizer III have enough formaldehyde to harden the emulsion? I presume any rapid fixer will do.
From a posting by Ron Mowrey, I see that I have to use the C-22 ferricyanide bleach to transform the lueco dyes to their final form.
Do NOT use E6 or C41 bleach to regenerate the silver halide image, as it fixes out part of the image. Use a standard rehal bleach with Ferricyanide.
The liquid (benzyl alchohol) should be good. There is about 5 ml/L in C22. The part with the CD3 should be a fine brown powder. If it is black or gooey it is bad. You have to replace it with fresh CD3 which is about 5.1 g/l IIRC.
Part b of the hardener should be a clear liquid.
The current Flexicolor Stabilizer contains no formalin at all and so you would have to use the original stabilizer.
You need a Ferricyanide bleach to convert the C22 leuco dyes into their final form.
I'm confused. AE-31 says to use fresh E-6 or C-41 bleach to regenerate the silver halide image, with the emphasis on fresh and free of hypo. Could I use the C-22 bleach for this step? (Saves one solution, and it would be hypo-free at that step in the process.)
Any suggestions on replacing part B of the hardener? Or can I use Flexicolor Stabilizer III as the hardener, which I already have? Or would the surfactant in it mess things up?
The writer of that is wrong then.
There is enough ammonia in either bleach to cause some fixation to take place causing loss of detail. Also, they are not designed for rehal work. Sorry. At EK we used a Rehal Ferricyanide bleach for this due to the very problem I am describing. It will work, but poorly, and with loss of image quality.
If you use a ferricyanide rehal bleach, you should use a sulfite clearing bath afterwards, and then a good wash before going into the color developer. Also, you must do the entire process in the light to reexpose the new silver halide. It will be very slow. You will have to expose the front and back of the film.
Kodak's AE-31 must be somewhat compromised to use standard products then.
So the Rehal Ferricyanide bleach would be Potassium Ferricyanide and Potassium Bromide. As in this page?
Hmm, the C-22 packaging says part B of the bleach is Potassium Ferricyanide and Potassium Bromide. Part A is Sodium Nitrate. I suppose I could just mix part B first, use it as the rehalogenating bleach, and then add part A for the final bleaching after redevelopment. Or will the Sodium Nitrate not cause any fixing of the film?
The clearing bath would be sodium sulfite, right? (Or Hypo Clearing Agent.)
Kodak does call for a substantial re-exposure with a No. 1 photoflood lamp. They also call for a 15 minute wash after bleaching.
The entire process from bleaching through redevelopment and fixing can be done in the light, right? Plus there's no harm in waiting a while between the bleach step and the redevelopment, since I'd need to take time to add part A to the bleach.
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The bleach in your reference contains thiourea which is a FIXING AGENT. OMG, you will destroy the image totally!!!!!!! It also contains HYPO.
Please read up on things and understand them before you leap. You appear to have completely misunderstood this process!
I was referring the formula later in that page:
Stock Solution A
Potassium ferricyanide 64 g
Potassium bromide 30 g
WTM 250 ml
That corresponds with other pages I've been looking at on rehalogenating bleach.
My understanding is that the rehalogenating bleach turns the metallic silver in the negative back to a silver halide, then I re-expose it to a lot of light. That gives me an exposed negative, which the color developer will then develop and activate the dyes that are still (somewhat) in the emulsion. Then I bleach and fix, and have a color dye negative. I realize the results will be pretty lousy, but I'm really curious to see the first roll of color film I took developed in color.
I'm trying to pull this off without winding up with a huge stock of leftover chemistry. The C-22 kit was a modest investment, although I'm going to have to muster a lot of bottles to store it in once mixed.
Would there be any hypo or fixer in the C-22 bleach? The 1965 BJP "formula" for C-22 bleach is:
potassium ferricyanide 40g
potassium bromide 15g
disodium phosphate (anyhdrous) 10g
water to make 1l
I don't have Kodak's formula, I just know that the "hazardous" ingredients in the kit are Potassium Ferricyanide, Potassium Bromide, and Sodium Nitrate. Do these sodium compounds give them fixing properties, or are they preservatives or pH buffers? Obviously, for the normal use of the C-22 bleach, it would be fully OK if it did some fixing, bu that's not OK for my use.
Trying to see if I can use the C-22 bleach for this as the ingredients for the rehalogenating bleach will set me back $32 at the Formulary, more than the C-22 kit cost.
I also hope my CD-3 is OK, since the Formulary doesn't stock it.
Well John, interesting that you ask that.
We used to use the C-22 bleach as our rehal bleach!