hardener in developer

Discussion in 'Silver Gelatin Based Emulsion Making & Coating' started by kevin klein, May 30, 2007.

  1. kevin klein

    kevin klein Member

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    Can Chrome Alum be used in developer?

    I tried plain Alum but it would not go into solution with the developer.
     
  2. Tom Hoskinson

    Tom Hoskinson Member

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    What film are you working with? Most modern films already have hardened emulsions.

    Some Efke films have rather soft emusions. I shoot a lot of Efke 25 and Efke 100 and I've never found it necessary to use a hardener - either pre-development or post development.

    The only film I've pre-hardened was Kodak ektachrome E4 false color IR film. I pre-hardened it in a formaldehyde hardener (Kodak SH-5) before high temperature processing it in E6 chemistry.
     
    Last edited by a moderator: May 30, 2007
  3. kevin klein

    kevin klein Member

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    I am using my own emulsion.
     
  4. narigas2006

    narigas2006 Member

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    maybe i am wrong, but chrom allum wont harden the film straight away. maybe paraformaldehide would do a better job.
     
  5. Photo Engineer

    Photo Engineer Subscriber

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    Paraformaldehyde decomposes into formaldehyde in solution. It can fog film if mixed with the developer.

    Chrome alum is a slow hardener and should not be added to the developer either.

    If you must harden, either use a hardener and wash before the developer or after the developer.

    PE