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  1. #21

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    The OF-1 formula looks interesting, but why is the alkali necessary? Doesn't it work if it's neutral (or becomes acidic through contamination)?

  2. #22
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    Quote Originally Posted by Ole
    I have just finished my first bottle of TF-4, and it's going to be my last. The ammonium smell is far stronger than from my own recipe, without significant increase in speed or capacity.

    Ole

    Nice to know the homemade stuff is as good or better than the bottled one!

    Cheers,

    Jorge O
    Curitiba - nice place to live, if you don't care about the weather...

  3. #23
    Ole
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    Quote Originally Posted by psvensson
    The OF-1 formula looks interesting, but why is the alkali necessary? Doesn't it work if it's neutral (or becomes acidic through contamination)?
    It works just fine. But I prefer to have a buffered solution of known pH, as it makes everything a lot more predictable. Both alternatives give a pH of about 8.5, which is just enough to be stable and wash out easily.

    I know from experience that acidic ammonium fixers bleach highlights in prints, and I assume they also lose shadow detail in film. I have also established to my own satisfaction that this does not happen with alkaline fixers, at least not without ridiculously long fixing times or very sensitive processes (read: van Dyke).

    That's why I put alkali in it.
    -- Ole Tjugen, Luddite Elitist
    Norway

  4. #24

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    Thanks, that's interesting. I've saved the formula. I've tried using plain sodium thiosulfate + sulfite. That worked fine for paper and Tri-X, but wouldn't quite fix Delta 400 to satisfaction, so it's interesting to see a nice and simple formula for rapid fix.

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