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  1. #11

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    I just sent you an email with the PDF file

    My first attempt at B&W reversal was with kodachrome...and it looked beautiful.

    Would the acid/dichromate bleach from BW reversal work in a color process - or is that bleach harmful to color dyes?

  2. #12

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    Ah...I had tried extra Blix...but it didn't do much..and I don't think it was expired.

    I got the couplers from Rockland Colloid...from their "selectachrome" product..which is now called "Polytoner"

  3. #13
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    Ok, here are a few thoughts.

    1. Thanks, I read the document and it is 'modern' having been revised in April of 1999. Unfortunately, that will not work. IDK why they published it. Acidic hypo is known to bleach and fix (blix) finely divided sillver, but I don't think it will work on this time scale. It is much too slow. The photo flo might help speed things up, but I doubt it. A dichromate bleach will remove all silver image. You will end up with blank film. At best, a tiny amount of silver sulfide might remain.

    2. Many couplers are what are called 4 equivalent, and they need a ferricyanide bleach to oxidize them and form the final dyes. Modern films contain 2 equivalent couplers which form dyes in the developer. I cannot tell what Rockland sent you, but I would suggest using a sulfite stop after each developer, with a good wash. Then after the final developer and sulfite stop with wash, use a ferricyanide bleach (with bromide) and then use a fix and wash. This should clear coupler and developer after each color development, and should oxidize all leuco dye to the final colored form.

    The Kodachrome formulas are published for all to see in the US patent. It is under the names of R. Bent and R. Mowrey. Sorry, I don't have my copy here to give the number, but I have posted it several times on APUG.

    PE

  4. #14

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    thanks!

    I did this back in 2000 and I think they sent me the MSDS on their couplers, but I don't think I have that information anymore..I'll have to ask them again

  5. #15

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    found the MSDS...You'll notice these are the "wrong" colors...Rockland gives you a table for how to mix the couplers to get different colors.

    I'm assuming the last entry is in all 3 coupler bottles

    here it is:

    ================================================== =========================
    Ingredients/Identity Information
    ================================================== =========================
    Proprietary: NO
    Designation: RED COUPLER
    Ingredient: 4-NITROPHENYLACETRONITRILE
    Ingredient Sequence Number: 01
    Percent: 10
    NIOSH (RTECS) Number: N/A
    CAS Number: 555-21-5
    --------------------------------------------------------------------------
    Proprietary: NO
    Designation: YELLOW COUPLER
    Ingredient: P-CHLOROACETOACETANILIDE
    Ingredient Sequence Number: 02
    Percent: 10
    NIOSH (RTECS) Number: N/A
    CAS Number: 101-92-8
    --------------------------------------------------------------------------
    Proprietary: NO
    Designation: BLUE COUPLER
    Ingredient: 2,4 DICHLORO 1-NAPHTHOL
    Ingredient Sequence Number: 03
    Percent: 10
    NIOSH (RTECS) Number: N/A
    CAS Number: 2050-76-2
    ---------------------------------------------------------------------------
    Proprietary: NO
    Ingredient: 2-BUTANONE (METHYL ETHYL KETONE) (MEK)
    Ingredient Sequence Number: 04
    Percent: 90
    NIOSH (RTECS) Number: EL6475000
    CAS Number: 78-93-3
    OSHA PEL: 200 PPM
    ACGIH TLV: 590 MG/CUM
    Other Recommended Limit: 590 MG/CUM
    ================================================== =========================

  6. #16
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    Ok, those are the 3 couplers used in an old book by Leadly and Stegmeyer. They work slowly with CD-4, but will still work ok. The MEK is just a solvent, as the 3 compounds you have there are rather insoluable in base. Leadly and Stegmeyer used acetone instead of MEK, and you could use alcohol as that would be even better. So, here goes.

    Rem jet removal
    wash
    D-19 first developer
    wash
    red exposure
    C41 + napthol (about 0.2 grams / liter to start)
    stop + sulfite
    wash
    Blue exposure
    C41 + acetanilide (about 0.2 g/l for starters)
    stop + sulfite
    wash
    white light exposure or E6 reversal bath
    wash
    C41 + nitrile (about 0.2 g/l for starters)
    stop + sulfite
    wash
    ferricyanide + bromide bleach
    wash
    hypo
    wash
    photo flo
    dry

    This is based on L&S roughly. They did it with single layers, so you will probably have to use more coupler. Use the developers at once, as these are one-shot developers. You also might find that it works better at pH 11 with a Phosphate buffer, as if IIRC that is where the Kodachrome developers are for better activity.

    PE

  7. #17

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    thanks!

    so it's normal acetic acid stop bath plus sodium sulfite?

    the developer that comes with the Rockland Colloid kit is supposed to be mixed with alcohol...I assume that's for helping the couplers dissolve like you said


    "You also might find that it works better at pH 11 with a Phosphate buffer, as if IIRC that is where the Kodachrome developers are for better activity."

    is this pH 11 for the D-19 or the color developer?

  8. #18

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    Quote Originally Posted by DarkroomExperimente View Post
    I just sent you an email with the PDF file

    My first attempt at B&W reversal was with kodachrome...and it looked beautiful.

    Would the acid/dichromate bleach from BW reversal work in a color process - or is that bleach harmful to color dyes?
    Could I get a copy of that PDF? Sounds like an interesting read...

  9. #19
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    Quote Originally Posted by DarkroomExperimente View Post
    thanks!

    so it's normal acetic acid stop bath plus sodium sulfite?

    the developer that comes with the Rockland Colloid kit is supposed to be mixed with alcohol...I assume that's for helping the couplers dissolve like you said


    "You also might find that it works better at pH 11 with a Phosphate buffer, as if IIRC that is where the Kodachrome developers are for better activity."

    is this pH 11 for the D-19 or the color developer?
    It is pH 11 for the color developers.

    The stop is 2% acetic acid + 10 g/l of sodium sulfite (either anh or monohydrate, this isn't exact).

    The pamphlet is interesting but moot as the method does not appear to work with current films.

    PE

  10. #20

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    <img src="http://i260.photobucket.com/albums/ii36/DarkroomExperimenter/kchrometest-thumb.jpg"></img>

    this is what I got from my experiment back in Feb of 2000

    the actual image looks much muddier and fainter....I increased saturation in Photoshop...probably upped the contrast too

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