Where to find EFS?

Discussion in 'B&W: Film, Paper, Chemistry' started by baachitraka, Apr 25, 2012.

  1. baachitraka

    baachitraka Subscriber

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    It is indeed very interesting read about measuring SBR with incident meter as described in BTZS. But there are few things which are unsettling for me.

    If I choose APX 100 to develop with Rodinal 1+50 and compute SBR as described above, I still need to know EFS and development times. How can I find these unknowns?
     
  2. baachitraka

    baachitraka Subscriber

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    I do not have any facility for testing a film, so I wonder are there any charts for

    - SBR vs EFS(Effective Film Speed)

    - SBR vs Development times

    available for APX 100 or any slow speed with any developer.
     
  3. Bill Burk

    Bill Burk Subscriber

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    Look at the Agfa Datasheets for Gamma-time curves. This information can be used to figure out SBR vs Development times.

    If you develop to the manufacturer's recommended times, you should achieve near the rated speed.