Plus X reciprocity

Discussion in 'B&W: Film, Paper, Chemistry' started by Craig, Mar 1, 2005.

  1. Craig

    Craig Subscriber

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    I'm going to be doing a shoot of building interiors, natural light only, and its pretty dark inside. Typical exposures are in the 30 second F8 range. I was planning to use up a box of Plus X in 4x5 that I have, but don't have the reciprocity data sheet.

    Will I need to lengthen the exposure time and/or increase the development at these light levels? Artifical light isn't an option, so I'm stuck with these long exposures.
    I've also got some HP5 if that will work better.

    Craig
     
  2. titrisol

    titrisol Member

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    Kodak PDF here:
    http://www.kodak.com/global/en/professional/support/techPubs/f8/f8.pdf

    If Indicated
    Exposure
    Time Is
    (Seconds)
    Use This
    Lens-
    Aperture
    Adjustment
    OR
    This
    Adjusted
    Exposure
    Time
    (Seconds)
    AND
    Use This
    Development
    Adjustment

    Indicated exp Adjust by or expose by and develop adjust:
    1/100,000 +1 stop Adjust aperture +20%
    1/10,000 +1⁄2 stop Adjust aperture +15%
    1/1,000 None None +10%
    1/100 None None None
    1/10 None None None
    1 +1 stop 2 –10%
    10 +2 stops 50 –20%
    100 +3 stops 1200 –30%
     
  3. Craig

    Craig Subscriber

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    Exactly what I need, thanks!
     
  4. Deckled Edge

    Deckled Edge Member

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    Craig,
    Notice that for increasing exposure times over 1 sec. you will decrease, not increase, the development. Contrast inherently increases with the exposure time, so you counteract that with minus development.