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Thread: MaxPyro

  1. #11

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    Thanks for the corrections as to cost....I neglected to note the volumes.

  2. #12

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    Does anyone know what is in it to make it special?

  3. #13

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    Quote Originally Posted by john_s View Post
    Does anyone know what is in it to make it special?
    Unlike PMK the Max Pyro formulary is proprietary and has not been released.

    My understanding that one of the major improvement over PMK is less B+F. One way to get this would be with the addition of ascorbic acid, as was done with Rollo Pyro, which is PMK on steroids.

    The addition of ascorbic acid would also make PMK more energetic, which would result in shorter development times.

    Just speculation on my part as to what I might have done to improve PMK. I don't know for fact any more than the rest of you.

    Sandy King
    Last edited by sanking; 07-23-2009 at 11:17 PM. Click to view previous post history.

  4. #14
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    It could be like Pyrocat MC but with a different B part. Pyrogallol can work with a lower pH. I have used PMK with TEA as part B. It easily gives the 9.5 pH required. If you are accustomed to mixing your own Pyrocat, you could try substituting pyrogallol for catechol. The color of the stain will be different, as Sandy has previously noted. When you are playing around with these things, note that in many cases, ascorbic acid is more of a substitute for bisulfite than for any of the developing agents. It promotes the synergism between catechol and Phenidone or Metol or paraminophenol, whichever one you are using. As you see in the formula for Pyrocat MC, there are only 4 grams of ascorbic acid in a liter of stock solution.

    Playing with these things reminds me of the admonition of a professional oboist. "You can't learn to play the oboe unless you play with it." He meant that if you don't learn what causes bad sounds (which are easy to make on the oboe) you won't know how to avoid them. That applies to most art forms. You explore the limits until you know where they are because the artist is one of the limits, and we're all different.
    Gadget Gainer

  5. #15
    Ian Grant's Avatar
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    If you take a formula like Pyrocat MC and substitute the Pyrocatechin with Pyrogallol you effectively have an Ilford Pyro-Metol developer, the only real difference is the dilutions. A Phenidone/Pyrogallol version is shown in one of Ilfords Patents.

    Ian

  6. #16
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    Ian. how effective is "effectively"? Is it one of those patents that seeks to cover all possible combinations of pyro and Metol? How about a Pyro-Metol-Ascorbic acid-TEA single solution concentrated staining developer?
    Gadget Gainer

  7. #17
    Ian Grant's Avatar
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    ID-4 Pyro-Metol Developer

    Part A
    Metol 4g
    Potassium Metabisulphite 25g
    Pyrogallol 25g
    Water to 1 litre

    Part B
    Sodium Carbonate (anhyd) 75g
    Water to 1 litre

    To Use: 1 Part A + 1 Part B, dish develop for 2-3 minutes @ 20°C

    The Phenidone version (in Kendall's original Patent) just substitutes O.4g Phenidone for the 4g Metol.

    If this was diluted further it might be interesting.

    Ian

  8. #18
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    I tried it out and the results resembled Pyrocat HD in terms of the lower base+fog (compared to PMK). The color of the stain was more of a brownie-green than a green-green, which leads me to believe that the alkali is either a carbonate or a blend of sodium metaborate and a carbonate of some sort. Bottom line is that the results were not noticeably different than I would get from the vastly cheaper Pyrocat HD, so I yawned and put the bottles toward the back of my shelf.
    I just want to feel nostalgic like I used to.


    http://www.clayharmon.net - turnip extraordinaire

  9. #19

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    Thanks Clay. One surmises that most others here feel as you do.

    Ed

  10. #20
    Jim Noel's Avatar
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    I would use it up rather than putting it to the rear of the shelf. The money is spent - might as well use it rather than waste he money.
    [FONT=Comic Sans MS]Films NOT Dead - Just getting fixed![/FONT]

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