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  1. #21

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    Quote Originally Posted by Nicholas Lindan View Post
    Another fixing agent is P. Cyanide - used by wet-plate/tin-type purists.
    It just astounds me that people do this. I'm not a fainting flower about chemistry generally, but KCN is scary stuff.

    -NT
    Nathan Tenny
    San Diego, CA, USA

    The lady of the house has to be a pretty swell sort of person to put up with the annoyance of a photographer.
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  2. #22
    mhcfires's Avatar
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    Quote Originally Posted by ntenny View Post
    It just astounds me that people do this. I'm not a fainting flower about chemistry generally, but KCN is scary stuff.

    -NT
    It must be good stuff, they used in gas chambers for years. It will kill you dead!
    Michael Cienfuegos


    If you don't want to stand behind our troops, please feel free to stand in front of them.

  3. #23
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    Quote Originally Posted by vickersdc View Post
    I gotta get me on a chemistry course, sulphites, sulphates, halides, chlorides, chlorates... lets call the whole thing off... (sorry, just burst into a little bit of song there).

    :0)
    Get yourself a copy of "Elementary Photographic Chemistry" compiled by the fine folks at Eastman Kodak.

    My copy has a cover price of 1.99usd but I think it ran 8 bucks on ePay and I got lucky. They usually cost more. I've seen some unrealistic prices for it recently.

  4. #24

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    Quote Originally Posted by brucemuir View Post
    Get yourself a copy of "Elementary Photographic Chemistry" compiled by the fine folks at Eastman Kodak.

    My copy has a cover price of 1.99usd but I think it ran 8 bucks on ePay and I got lucky. They usually cost more. I've seen some unrealistic prices for it recently.
    Thank you for the heads-up on that - I'll keep a lookout for it, sounds like it might be just what I need to gain a better understanding of the underlying chemistry behind it all.
    Creative Image Maker e-magazine is back! Find out more at http://creativeimagemaker.blogspot.com

    Thank you.

  5. #25
    Athiril's Avatar
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    You can get sulphur really cheaply at some shops, such as K-Mart here in Australia at the gardening section.

    And sodium sulphite is easy to find (or make from metabisulphite) one of which will be in shops, and cheaply available.

    Heating sulphur and sulphite in an aqueous solution should give you thiosulphate, you should know when the reaction is taking place as sulphur is not soluble in water and will start dissolving as it converts to thiosulphate iirc.

    If you get sodium metabisulphite and ammonium hydroxide (household ammonia) you should be able to make a mix of sodium sulphite and ammonium sulphite, in which should give you a mix of sodium thiosulphate and the faster ammonium thiouslphate I think.

  6. #26

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    Quote Originally Posted by Athiril View Post
    Heating sulphur and sulphite in an aqueous solution should give you thiosulphate, you should know when the reaction is taking place as sulphur is not soluble in water and will start dissolving as it converts to thiosulphate iirc.
    It's not that simple. When you heat sulfur and sodium sulfite you are also going to get other sulfur compounds besides thiosulfate.
    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

  7. #27
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    Quote Originally Posted by brucemuir View Post
    Get yourself a copy of "Elementary Photographic Chemistry" compiled by the fine folks at Eastman Kodak.
    Free (as if anything is free...) at google books:
    http://books.google.com/books?id=cFwtAAAAYAAJ

    A reprint is in print and available at Amazon.
    DARKROOM AUTOMATION
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  8. #28
    Photo Engineer's Avatar
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    It should be noted that that particular book has a few errors in it and it is quite out dated. You may want to get a copy of Eaton's book which is a bit more modern and includes color chemistry.

    PE

  9. #29

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    Sodium thiosulfate and even ammonium thiosulfate are quite reasonable and should be available most everywhere. Please, leave the manufacture to the chemical companies. They know what they are doing.
    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

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