Thiocyanate: Sodium Versus Potassium

Discussion in 'Color: Film, Paper, and Chemistry' started by Snapshot, Nov 15, 2007.

  1. Snapshot

    Snapshot Member

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    Hi All,

    I've found a formula for a E-6 colour first developer that uses potassium thiocyanate. However, I have sodium thiocyanate on hand. Are the two exchangeable for this purpose? My gut feel says they are but I don't want to presume that is the case.

    Any thoughts?
     
  2. Photo Engineer

    Photo Engineer Subscriber

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    Yes. You must adjust the amount of salt based on molecular weight though.

    PE
     
  3. Snapshot

    Snapshot Member

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    Understood. Thanks for the confirmation. I'll have to add 20% more Sodium Thiocyanate.