• 01-31-2013 12:53 PM #0
    padraigm
    padraigm is offline

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    Film speed testing question using waybeyond excel sheet

    film graphs2.pngHi All,

    Need a little help here. I am using Ralph Lambrech's spread sheet to determine my film speed.

    A 21 step wedge was contact printed Hp5+ at f/8 .7 seconds in Xtol 1:1 @20c for the 4, 5.5, 11, and 16 minute intervals.

    Could someone who is familiar with this procedure look at my graphs and tell me what is wrong? I am thinking my exposure is still too short as I am missing too many data points in the shorter development times?

    I have a macbeth TD500 and I zeroed using the instruments light source. A calibrated step wedge indicates measurements are accurate.

    Any help would greatly be appreciated.

    Thanks


    film graphs.png
    Last edited by padraigm; 01-31-2013 at 12:58 PM. Click to view previous post history.
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