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  1. #21
    Photo Engineer's Avatar
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    Well, IDK what AF9 is nor do I know what AF2000 is. I have forgotten if I even ever knew them by those names. Internally we used different nomenclature so, I can recognize them now only by their chemical names.

    And no, not all antifoggants are equal. Some go after a specific layer in color films and papers and others are generic. So, it is important to know the intent and name of the AF. I know of 3 antifoggants that go after respectively, the cyan, magenta and yellow in color paper in that order. You can use any combination to fight any particular fog type.

    PE

  2. #22

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    Quote Originally Posted by Photo Engineer View Post
    Also, if someone can remind me what AF2000 is, I might have a substitute.
    According to the MSDS it is 5%-10% (weight) Sodium-3-nitrobenzenesulphonate.

  3. #23
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    Quote Originally Posted by David Grenet View Post
    According to the MSDS it is 5%-10% (weight) Sodium-3-nitrobenzenesulphonate.
    That is not generally considered to be an antifoggant, but rather an anti foamant. Hmmm. I'll have to think about that.

    PE

  4. #24
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    IIRC, h2408 or h2409 from KODAK (effects of chemical & mechanical variations in ECN2) shows that halving the AF-2000 concentration has no effect at all. Doubling it, instead, had some effect. Sadly they didn't test for omitting it completely. However, this makes me think that this is not super-important part and I'd rather just omit it than cross-process in C-41.

    ECN-2 indeed used "Anti-Foggant No 9" before and it was flammable and replaced with AF-2000 (proprietary liquid concentrate) which, according to some of the processing manuals, has very high stability in the developer IIRC.

    Minimum order size is 2 x 2 liter bottles IIRC (which is very much at 5 ml/l), and KODAK directly may be the only dealer?

  5. #25
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    I happened to find an older version of h2408 ( http://sysdoc.doors.ch/KODAK/h2408.pdf ) where AF-9 is used instead of AF-2000, and that test goes to concentration of 0 g/l! (See page 9.) Omitting the antifoggant seems to give Dmin a rise of 0.02 to 0.04. Doesn't sound so problematic at all. It shows a green crossover of 0.04 but can you see a crossover this small in real images?

    The bromide level seems to play a MUCH bigger part and it seems possible to compensate it carefully to address the green crossover, but for me it seems that it's hard to even measure that accurately at home! (1.15 g/l instead of 1.20 g/l, when AF-9 omitted.)
    Last edited by hrst; 02-24-2010 at 01:11 AM. Click to view previous post history. Reason: language fix

  6. #26
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    Well 5% - 10% by weight is 50 - 100 g/L. That is rather exorbitant for an antifoggant don't you think??????

    Wow, we used to use 1 - 100 mg / L for antifoggants, so the appelation ANTIFOAMANT seems more likely to me. And, it is not unknown for other ingredients to affect curve shape.

    So, I leave it with you.................

    I'm confused.

    PE

  7. #27
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    AF-2000 is used at 5.0 ml/l in the developer, so if the concentrate is 5% - 10% it would be 250 - 500 mg/l in the developer...

  8. #28
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    Quote Originally Posted by hrst View Post
    AF-2000 is used at 5.0 ml/l in the developer, so if the concentrate is 5% - 10% it would be 250 - 500 mg/l in the developer...
    Yes, I see that I misunderstood the post about the MSDS. Sorry.

    I still have a hard time seeing that as an antifoggant. It must be very weak. Usually, antifoggants are complex heterocycles or contain sulfur groups.

    PE

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