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Thread: Acid Developers

  1. #1
    Ian Grant's Avatar
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    Acid Developers

    It appears that you can use an acid developer, there's a German Patent from 1907. In think I already knew this, Amidol springs to mind.

    Either you use an acid fore-bather or an acidified developer. Half a percent Sulphuric acid

    German Patent no is: 29,937, now I just need to find and get translated

    Ian

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    keithwms's Avatar
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    "Only dead fish follow the stream"

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    Steve Smith's Avatar
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    Aren't most developers based on an acid buffered to become alkaline?

    Steve.
    "People who say things won't work are a dime a dozen. People who figure out how to make things work are worth a fortune" - Dave Rat.

  4. #4
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    There are developers using salts of iron, chromium or vanadium that work in acidic solution.
    Gadget Gainer

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    I found this. It's ancient. I have no idea of how or even if it works.

    Acid amidol film developer (for reduced contrast)
    Sodium sulfite 13 g
    Potassium metabisulfite 5.2 g
    Potassium bromide 500 mg
    Amidol 2.6 g
    WTM 1 l
    Development times are long (2 to 12 hours)

  6. #6

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    This intensifier might work as a developer too: http://www.apug.org/forums/forum230/...tensifier.html

  7. #7
    Ian Grant's Avatar
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    I think your intensifier is a physical developer. I do have quite a lot of literature about them but most is back in the UK.

    Ian

  8. #8
    Ian Grant's Avatar
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    I've just found a Kodak Acid "Warm tone" developer formula for Velox, based on Protosulphate of Iron - Ferrous Sulphate

    Once I've converted the formulae, and put them in my database, I'll post then but it looks like over a 100 new developer formulae to add.

    Ian

  9. #9

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    I really like Amidol for paper, and have wondered about using it for sheet film. I may give it a go some day. Not sure I'd be interested in a formula that requires a long time, e.g. more than a couple of hours. I'd be concerned about the emulsion swelling and/or being more subject to physical damage.
    Honey, I promise no more searching eBay for cameras.

  10. #10

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    Quote Originally Posted by Ian Grant View Post

    German Patent no is: 29,937, now I just need to find and get translated

    Ian
    post a link to it or tell me how i can find this.
    if it's not too complicated and/or long, i can give you a brief translation. or i can try to.

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