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    Re: Are higher altitude sights inherently less accurate?
    From: Alexandre Eremenko
    Date: 2012 May 2, 11:54 -0400

    Yes, there are more factors that can contribute to your errors
    with higher altitudes. One of them is the sextant arc imperfection.
    I've seen many sextant certificates on e-bay.
    In almost all cases when a certificate is available the arc errors
    increase towards the end of the arc.
    What sextant do you use?
    There is also a pure mathematical reason: it is harder to keep the
    sextant vertical by swinging the arc (I mean natural horizon).
    With artificial horizon it is even harder to align
    exactly, and to ensure that the
    sextant plane is vertical.
    On Wed, 2 May 2012, Randall Morrow wrote:
    > I have been loking at averages of my sights and higher altitudes seem to 
    have larger intercepts. Using an AH and reading Hs of over 100 degrees, Ha 
    over 50.  It seems to take longer to find high altitude bodies in the mirror 
    but is there something in the process which introduces more risk of error?
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