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  1. #21
    RalphLambrecht's Avatar
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    Quote Originally Posted by john_s View Post
    Nicholas, I think i remember reading that the product called Calgon is actually not the same in all parts of the world. I don't remember where I read it. Richard Knoppow from time to time posted on the pure-silver list a formula like the one you have given but with EDTA instead of Calgon. From one of his posts:
    <start quote>
    Sodium Sulfite, dessicated 100 grams
    Sodium Bisulfite 20 grams
    EDTA tetra-sodium salt 1 gram
    Sodium Citrate 1 gram
    Water to make 1 liter
    <end quote>

    And from Ryuji Suzuki's now-defunct web site:
    <start quote>
    Kodak Hypo Clearing Agent contains EDTA and sodium citrate to reduce the calcium scum. With hard water, sulfite in the wash aid forms insoluble calcium scum unless EDTA is added. These are also useful in preventing precipitation of aluminium hardener that may be carried over from the fixer (if acid hardening fixer is used).
    <end quote>

    I just use the sulphite plus a little metabisulphite (=bisulphite). Very cheap if you mix from bulk chemicals, and toss it at the end of the day.
    fully agree
    Regards

    Ralph W. Lambrecht
    www.darkroomagic.comrorrlambrec@ymail.com[/URL]
    www.waybeyondmonochrome.com

  2. #22

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    Quote Originally Posted by dnjl View Post
    How long does the sodium sulfite last in powder form? I bought a 19L pack of Kodak HCA because I couldn't get anything smaller. I mix half a teaspoon just prior to using. Does the powder oxidize too, or is that only if you mix it with water?
    Seeing the thread today about Selenium toner led me to google up related questions. And this old thread popped up. Referring to one of the posts as quoted leads me to ask a question. The poster claims he just spoons out a small amount of Kodak HCA powder and mixes it as needed. Now we all know you can't do that with powdered developer for instance because a relable equality of distribution of the various components can never be known. Is it not the same problem with HCA? Or was the poster ignorant and didn't know you can't do this? Is the HCA powder out of the package a homogenous compound allowing small portions to be spooned out?

  3. #23
    MattKing's Avatar
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    Quote Originally Posted by Tom1956 View Post
    Seeing the thread today about Selenium toner led me to google up related questions. And this old thread popped up. Referring to one of the posts as quoted leads me to ask a question. The poster claims he just spoons out a small amount of Kodak HCA powder and mixes it as needed. Now we all know you can't do that with powdered developer for instance because a relable equality of distribution of the various components can never be known. Is it not the same problem with HCA? Or was the poster ignorant and didn't know you can't do this? Is the HCA powder out of the package a homogenous compound allowing small portions to be spooned out?
    Kodak HCA consists of just two components: Sodium Sulfite and Sodium Metabisulfite.

    As I understand it, the Sodium Sulfite does the work, and Sodium Metabisulfite helps preserve the solution once it is mixed.

    Most likely, the Sodium Sulfite constitutes the majority.

    If one is intending to use the result one-shot, the presence of preservative is rather unimportant.

    So unlike developer, where the relative ratios of the two components are important, using slightly un-homogenous HCA is unlikekly to cause problems.

    You do need to use somewhat more than the minimum though, and that combined with the one-shot use means that it isn't the most economical way to use it.
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  4. #24

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    Matt, thank you. While I have come to accept you as a credible poster, I have seen other formulas for Kodak HCA which listed more ingredients than just these 2, and even seen the formula called entirely "proprietary". At any rate, this thread and others are not at all kind to Heico Perma Wash. It was not until the late 80's when I finally jumped on the Perma Wash bandwagon, though still reticent about it. In the late 70's and 80's, maybe 90's, Heico Perma Wash was the big deal of its day--a true miracle formula. I have a bottle now I've had for 7 or 8 years, and threw out an older bottle that smelled a very strong ammonia-like smell.
    I never was a true Perma-Wash convert. Having said all this, I wonder if I've gone my whole 42 years since the first time I developed anything, and feeling a bit foolish that a tablespoon of Sodium Sulfite in water is all I ever needed. Heck, I can buy Sulfite by the bushel for peanuts. And I'm beginning to wonder if I should just do that.

  5. #25
    MattKing's Avatar
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    Tom:

    The two ingredient listing is taken directly from the back of a Kodak packet. I probably should have added the word "active" before "components" because as noted earlier in the thread there are also components designed to deal with hard water.

    You probably aren't doing this, but are you sure that you aren't confusing Kodak Hypo Clearing Agent with Kodak Hypo Eliminator? The latter, which is long discontinued and now considered to be unwise to use, is very different than HCA. There is information about that earlier in this thread as well.

    The Kodak packaged stuff (or similar competitors' products) has advantages flowing from the precision of its makeup and accuracy in use when mixed and diluted per instructions. Those advantages are essentially advantages of convenience and predictability. If your water isn't too unusual, have a source of quite pure Sodium Sulfite and are able to be sufficiently precise in its "tablespoon" use, there really is no reason not to use that alternative.
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  6. #26

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    Thanks. You've answered my question. No, I know about the ammonia/peroxide after-treatment and it's variants. Maybe I'll compromise with myself and buy Kodak HCA and spoon out powder as I need it and hope for homogeneity of the powder and throw out this Heico Perma Wash that I always was suspicious of. I didn't jump on that train for a long time. Back in the day, it was the cat's pajamas among the "in" crowd. I was never very "in" with that ilk, truth be known. Perma Wash and koolaid seemed to be favorites among certain photographic circles in that day. I always tended to rely on what the scientists at Kodak had tested and marketed.
    Last edited by Tom1956; 09-20-2013 at 12:27 AM. Click to view previous post history.

  7. #27

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    Kodak Hypo Test solution HT-1a can be used to check for the presence of residual hypo in prints. You can therefore check the usefulness of various clearing agents.
    A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.

    ~Antoine de Saint-Exupery

  8. #28
    RalphLambrecht's Avatar
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    yes, butI think ,I't's quicker and safer just to mix fresh washing aid.
    Regards

    Ralph W. Lambrecht
    www.darkroomagic.comrorrlambrec@ymail.com[/URL]
    www.waybeyondmonochrome.com

  9. #29
    RalphLambrecht's Avatar
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    THAT'S WHAT I'VE DONE FOR YEARS.
    Regards

    Ralph W. Lambrecht
    www.darkroomagic.comrorrlambrec@ymail.com[/URL]
    www.waybeyondmonochrome.com

  10. #30

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    For many years my practice has been to use the Perma Wash with film but to rinse for longer than Heico recommends. When rinsing film you also have to consider the type of fixer which was used. The non-hardening fixer is supposed to rinse out more readily. There are plenty of threads about modern films being sufficiently hardened so that hardening fixer is not required. Lately I have been using C-41 fixer diluted 1:3 with water. When the working solution is fresh it clears the film in 1:45 at 68F. I use a starting time of 4 minutes and test the leader for each new roll. I also filter the working solution on its way back into the bottle. I have always found Kodak HCA inconvenient because of the odd volume it makes up. Some people mix it with a smaller volume of water than recommended and then dilute it just before using it. I bought a new container of C-41 fixer yesterday and it now has both the RA-4 and C-41 markings.

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