calibration of 361T Transmission Densitometer

Discussion in 'B&W: Film, Paper, Chemistry' started by mitch brown, Jan 31, 2008.

  1. mitch brown

    mitch brown Subscriber

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    hi
    does this densitometer need to be calibrated to read neg densities or can you just zero it and then measure the negs. i would like to read pyro negs for a film speed test.
    thanks
    mitch
     
  2. Don12x20

    Don12x20 Member

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    When I bought my used 361T, I presumed I could just zero and read.
    It did read, but way off compared to my other densitometes (for optical; I had no reference to compare on the UV spectra).

    I bought the reference step table and ran the calibration (you can get manual off the website).

    now the readings for standard B&W film (not pyro) match the other denistometers, and the pyro negative readings changed substantially from the first reading.

    So, the answer is....it depends. My experience indicates you ought to recalibrate.