Na2 method?

Discussion in 'Alternative Processes' started by mark, Jan 18, 2005.

  1. mark

    mark Member

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    What is this?
     
  2. Monophoto

    Monophoto Member

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    I think its a form of Pt/Pd printing. Tillman Crane is giving a workshop at Peters Valley Craft Center on the subject this summer.
     
  3. Jorge

    Jorge Inactive

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    I dont know if he still does, but Arentz used to have a table of drop counts using sodium platinate as the restrainer as opposed to potassium chromate in his web site.

    I dont like the Na2 method much, some swear by it.
     
  4. mark

    mark Member

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    I read it on Arentz' web site and Saw it on another. What is it for? Yep, I have no clue what the hell a restrainer is or does.
     
  5. TPPhotog

    TPPhotog Member

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    Morten could tell you but I bet his are leather :wink:

    Here you go "Restrainer - chemical constituent of developing solutions which helps prevent reducing agents from affecting unexposed halides and converting them to black metallic silver". Found it here :smile:
     
  6. clay

    clay Subscriber

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    Na2 is a restrainer used in palladium printing to increase the contrast of the print. It acts by inhibiting the sensitivity of the solution. It affects highlight areas more severely than shadows and thus increases the resulting print contrast. Varying the amount of Na2 solution you add to your basic palladium-ferrric oxalate mix will allow you to fine tune the contrast. The downside to this method is that it uses a platinum compound that can significantly cool the tone of a palladium print. It is also useful only for pure palladium prints. The benefit of this method is that it does not cause graininess in the print like some other restrainers can when used in the larger quantities.