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Re: SNO-T tests

From: jean-philippe planas (no email)
Date: Wed Apr 12 2006 - 01:44:12 EDT

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    Dear Alex,

      Do you know what Bill Astra's calibration certficate states for that angle (38°). Is the correction 0" or is it something elese in which case the correct reading you obtain would be luck and corresponding to the addition of sevral errors zeroing themselves.
      Regards
      JPP

    Alexandre E Eremenko <> wrote:
      Dear Fred,

    Thank you for your message of Mon Nov 28 2005 12:21:44 EST.
    (It is listed on the list archive between April 2 and 3,
    so I can be excused for discovering it only today:-)

    I recall that you wrote (presumably in November):

    >Your data look very good. I am not sure, however, that you can
    >attribute the divergence of observation from prediction to arc error
    >with so few data.

    This was only a small sample of my data.
    Small but typical. To summarize my 2 years of obsevations
    I would say that I have an error of +.3 to +.7
    more frequently than I dont.

    And I almost never have negative errors.

    The most frustrating thing is that I measure one
    chosen distance of say 38 degrees night after night,
    many many times, taking all possible precasautions,
    and I obtain this +.3 error again and again.

    Then I take Bill's Astra, and the distance is OK.
    Then I take my SNO-T again and again get +0.3 error.

    I think human errors are excluded here (by Bill's Astra).
    Random errors are excluded by consistency of the biased results.
    So what is this, I don't really know:-(

    Alex.

    JPP

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