SBC Meter Characteristics vs. Selenium

Discussion in 'Exposure Discussion' started by kq6up, Dec 1, 2011.

  1. kq6up

    kq6up Member

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    I have a Gossen Luna Pro SBC (I love that meter), and a Sekonic L-398. They both agree 100% when the light source is white, but when the light source is the blue sky, the Selenium cell (Sekonic) reads hot by as much as a stop (or conversely the SBC reads low). Which cell most closely represents the way Panchromatic film handles its values? What spectral response more closely resembles the sensitivity of the human eye. I understand (from the Ilford Photography Manual) that the Silicon diode in the SBC is more sensitive to IR, but it has a filter in place to make the response closer to that of the human eye.

    Thanks,
    Chris Maness
     
  2. Stephen Benskin

    Stephen Benskin Member

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    This is from Photographic Materials and Processes. It might answer some of you questions.
     

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  3. kq6up

    kq6up Member

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    That is the best answer I have received on this topic. I cross posted this on other forums because I did not get an answer here.

    Thanks,
    Chris