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    Relative Importance of Accurate Timing of Sight for Lunars versus Altitude Sights
    From: Fred Hebard
    Date: 2003 Jun 9, 22:48 -0400

    It has taken me a long time to where I can consistently get my altitude
    sights to under 0.5' of arc from a known position on dry land, often,
    now, under 0.2' of arc.  A critical component of that has been judging
    the exact moment of contact and hitting the stop watch accurately at
    that moment.  After setting the angle, I generally wait for the object
    to converge with the horizon, or itself in the artificial horizon, and
    try to hit the stop watch when contact occurs.
    However, I always had a fair amount of luck with lunars, even before
    improving my timing technique for altitude sights.  That was back when
    I would look down at my watch after perfecting the contact and record
    the time.
    I still prefer this second method for lunars and believe it is the best
    for that observation.  That is because 12 seconds of time elapse, more
    or less, between each shift of 0.1' of arc in a lunar.  It doesn't make
    much difference whether you're 2-4 seconds out.  It's much more
    important to get the angle measured to the utmost precision possible
    than to time the sight accurately.  You need to concentrate much more
    on proper manipulation of the micrometer than on the time, like when
    checking index error by determining the semi-diameter of the sun.
    Any comments?

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