[HELP] Efke IR 820 and d-23... what is the "FORMULA"?

Discussion in 'B&W: Film, Paper, Chemistry' started by Enrico_Agostoni, May 23, 2012.

  1. Enrico_Agostoni

    Enrico_Agostoni Member

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    Dear "analogic" friends,

    Yesterday I bought an Efke IR 820 for my Pentax 6x7. For infrared photos I use an 600nm filter (and not a "classic" 720nm like Hoya IR72).

    So, according to the datasheet I have to expose my Efke to 6 or 9 ISO. (With the 720nm filter, the recommended exposure is at 3 ISO).

    I like develop my film with the Kodak D-23. But... with this Efke, I haven't found information about times and/or diluitions. :sad:

    Please.... can you help a "young" photographer? :D

    Thanks,

    Enrico.

    P.S.
    Apologies for my English. :wink:
     
  2. Keith Tapscott.

    Keith Tapscott. Member

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    Use the same time given for Kodak D-76 or Ilford ID-11.
     
  3. MDR

    MDR Member

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    Enrico I'd add a minute to the D76 times, 1 - 2 minutes longer dev. times than D76 seems to be the norm with D23.

    Buona fortuna
    Dominik
     
  4. Enrico_Agostoni

    Enrico_Agostoni Member

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    Grazie Dominik! :wink:

    So, for D76 stock, the time is 8/9 minutes, therefore The time of D-23 is 10/11 minutes. (stock diluition).

    Any suggestion for a dilution 1+3? maybe 20 minutes or more? :confused:

    Thanks!
     
  5. MDR

    MDR Member

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