Mocon -- XTOL-quality in a long-lasting concentrate

Mocon -- XTOL-quality in a long-lasting concentrate

  1. albada

    albada Member

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    albada submitted a new resource:

    Mocon -- XTOL-quality in a long-lasting concentrate - Mocon -- XTOL-quality in a long-lasting concentrate

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    Last edited by a moderator: Feb 6, 2016
  2. Rafal Lukawiecki

    Rafal Lukawiecki Subscriber

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    Congratulations, Mark, and thank you for doing this work. Without dedication of people like you, our craft would not advance much, anymore, as the big manufactures, sadly, no longer seem to do, or share with the world, any significant photochemical R&D.
     
  3. Bruce Osgood

    Bruce Osgood Membership Council Council

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    I echo Mark's statement, thanks for the work.
     
  4. zsas

    zsas Member

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    Well documented! When I do my next Formulary order I might just get some of these chems to give it a try! Congrats on your accomplishment and for all who contributed! I have to say, the thread where this was beings developed in was a bit over my head, I appreciate you doing such a nice post write up with actual mixing examples! This kind of care in good clear writing goes a long way towards somone like me (weekend darkroom hobbiest) actually trying this!
     
  5. kb3lms

    kb3lms Subscriber

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    Mark, thank you for all the work you have put into this project and the great write-up. I'm still working off my D-316 but will be trying Mocon soon.
     
  6. Griz

    Griz Member

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    I've followed this thread from the beginning with great interest, and I'd like to thank everyone that has contributed to the process! While I am NOT a chemist by any stretch of the imagination, I have learned a thing or two along the way, and I appreciate the dedication and hard work that has gone into this project!

    Congrats Mark!

    Griz :smile:
     
  7. michael_r

    michael_r Subscriber

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    Hi Mark,

    Just thought I'd post some more TMY-2 curves from a few batches including the newest I could find.

    Michael
     

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  8. john_s

    john_s Subscriber

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    Thank you Mark! What a job!

    If I have 8-mol sodium metaborate instead of 4-mol, and if I adjust for the molecular weight (x137.88/101.83) would the extra water of crystallization make much of a difference to the longevity of the concentrate? I don't need stupendous life: 6 months would be fine.
     
  9. Alan Johnson

    Alan Johnson Subscriber

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    John,
    I did the D-316 keeping test mentioned here:
    http://www.apug.org/forums/forum37/107623-progress-xtol-concentrate-48.html
    I started this before I knew there were 2 forms of the metaborate, 4-mol and 8-mol,aka Kodalk of which 1.354 times the weight is needed.
    The form I used was probably 8-mol Kodalk ,it is not labelled on the old pack but looks like some known Kodalk I bought later.
    So 8-mol is probably good for at least a year but I cannot say for sure.
     
  10. albada

    albada Member

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    Hi John,
    As Alan just posted, 8-mol will probably last long enough, especially if you keep the concentrate chilled or frozen.
    But if you use 8-mol, don't forget to increase the amount of concentrate you pour out when mixing.

    Everybody:
    Thanks for the kind notes. They're encouraging. Yes, I try to write clearly, even though I'm a software geek by profession. :smile:

    Mark Overton
     
  11. Steve Law

    Steve Law Member

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    I too, have 8-mol sodium metaborate instead of 4-mol. What do I need to do to compensate for this, if anything?

    Steven
     
  12. StephenT

    StephenT Subscriber

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    WOW! Great work Mark. I think I'll try to mix up a batch.
     
  13. Jeff S.

    Jeff S. Member

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    Just tried mixing this yesterday. My first attempt at mixing a developer from bulk chemicals. My question is, my concentrate has an orange tint. Is that to be expected? I got the mixture a little hotter than 75 C for the last ingredient. By the way, I used Phenidone instead of Dimezone S. Will try it today and report back.
     
  14. Photo Engineer

    Photo Engineer Subscriber

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    Congratulations Mark.

    PE
     
  15. Alan Johnson

    Alan Johnson Subscriber

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    The orange color is probably a small amount of diketogulonic acid, formed possibly at higher temperature due to oxidation.
    It is unlikely to have any significant effect as the pH mostly depends on the other ingredients.
    http://www.apug.org/forum/index.php?threads/ascorbate-chemistry-1.127463/page-3