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  1. #11
    mobtown_4x5's Avatar
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    I was told you can tweak the formula- more salt= more "fine grain" (grain dissovling) effect... can anyone confirm this...

  2. #12
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    The NaCl is a very weak restrainer. Its main use in fine grain developers is as a silver halide solvent. Remember, the first fixer for photo emulsions was brine. You don't want iodized salt because iodine is a stronger restrainer than bromine IIRC. You may be able to find the article "Salt to Taste" in the Photo Techniques back issues at www.phototechmag.com.
    Gadget Gainer

  3. #13
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    There seem to be more Microdol-(X) substitutes out there than you can shake a stick at.

    All approaches seem to take something like D23 (with more or less Metol) and to either add a restrainer (i.e. solvent action NaCl, KBr) or lower the pH (add bisulfite, boric acid or the alike) and thereby increase time of development and in turn solvent action of the sulfite or just do both. Besides the exact quantities used all aproaches seem to be pretty similar.

    The formula quoted by Anchel and Troop may not be identical to Microdol-X but there has been information dripping out of Ilford indicating that the formula is darn close if not identical to Perceptol. In my view it can be seen as the the basic approach to the problem.

    Stefan

  4. #14

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    Quote Originally Posted by Tom Hoskinson
    I see nothing to indicate that a silver sequestrant is necessary when you add NaCl to this metol/sulfite formulation. Phenidone/ascorbic is a different animal.

    From a post by Richard Knoppow on http://www.binbooks.com/books/photo/i/l/5DDE6AE25C

    Reportedly, Microdol-X contains a similar
    sequestering agent for silver although it doesn't show up on the MSDS.
    It may be either non-hazardous or present in too small an amount to
    require inclusion in the MSDS. The story I was told is that this
    substance is the difference between Microdol-X and the old Microdol.
    The purpose here being to eliminate dichroic fog, which is a very thin
    deposit of very finely devided silver (colloidal silver) on the
    surface of the film.

  5. #15

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    Quote Originally Posted by psvensson
    From a post by Richard Knoppow on http://www.binbooks.com/books/photo/i/l/5DDE6AE25C
    My comment was not based on the Kodak MSDS but on an independent spectroscopic analysis. Of course, Kodak may have changed the mixture since then...
    Tom Hoskinson
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    Everything is analog - even digital :D

  6. #16

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    I wonder if the Calgon is the silver sequestrant Knoppow is referring to. I got some interesting results when I added kosher salt to a Gainer-type brew of phendione, ascorbic acid and carbonate. The grains were small and very well defined little dots. Didn't look like a sulfite-free developer or a sulfite developer. Unfortunately, results were inconsistent and I had dichroic fog, so I abandoned the formula. But Calgon is readily available, so it's worth a shot.

  7. #17
    Ian Grant's Avatar
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    Quote Originally Posted by Joseph
    Tom: I had read the APUG Mic-X formula.

    1. How is Sodium Chloride (30 grams) different from Sodium Bisulfite
    (7.5 grams) for one liter of Mic-X?

    2. Does one liter require 7.5 grams of Metol or does 5 grams work OK?

    Thanks fo your info.
    I Know this is an old thread but as it's just been linked to:

    The Sodium Chloride is added as a mild silver solvent. Many years ago Iford published a leaflet suggesting adding Ammonium Chloride to certain of their developers to obtain finer grain but at the expense of a speed loss. It was published in:
    ILFORD TECHNICAL INFORMATION SHEET P10
    FINE GRAIN DEVELOPMENT

    It's the same principal as the addition of additional Bromide to a warm tone print developers is to reduce the grain size in the print.

    You can see that the amount of Sodium Chloride is high at 30gms per litre but it probably has a less side affects with regard to loss of shadow details etc.
    Last edited by Ian Grant; 02-09-2005 at 03:09 PM. Click to view previous post history.

  8. #18

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    Now that it's back from the dead, I might as well chime in that I've been experimenting some with a developer that has a lot of sodium chloride and no sulfite. It needs Calgon to prevent dichroic fog. I'll post more details when I've tried it a bit more.

  9. #19
    Ian Grant's Avatar
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    Quote Originally Posted by psvensson
    Now that it's back from the dead, I might as well chime in that I've been experimenting some with a developer that has a lot of sodium chloride and no sulfite. It needs Calgon to prevent dichroic fog. I'll post more details when I've tried it a bit more.
    Stick as much calgon in as you like it's not really the answer to dichroic fog.

  10. #20

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    Then why do I get dichroic fog with no Calgon, a little bit with 1 ml of Calgon, and none with 2 ml of Calgon? Done this a number of times. Have you tried?

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