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    Re: Franks Lunars calculator questions
    From: Alexandre Eremenko
    Date: 2012 May 4, 00:32 -0400

    I suppose Frank will give exact answers but I can tell
    you my own experience
    with this calculator.
    a) Pressure and height (for Indiana) never had any influence on the
    distance. So you don't need to bother with that.
    b) Though it is not needed for the lunars, the calculator gives
    the altitude precisely. So you can use it for reduction of ordinary
    (non-Lunar) sights, the feature which I used when studied Cook's
    observations. Fortunately for me, they also recorded their altitudes
    > As Alex mentioned I purchased a 7x35 scope, so playing with lunars again.
    > A few inputs of the lunars calculator puzzle me.
    > If I understand I am to enter pressure at sea level, yet at 600-800 ft
    > above sea level the pressure is lower, so refraction would be would be
    > slightly less.  Does the calculator somehow adjust for this?
    > What purpose does height of eye serve? Is there dip in body to body
    > observations?  If above sea level then it could adjust pressure, but if I
    > recall one of Frank's examples from Chicago, IL he listed height of eye as
    > 6 feet. It might be relavent in altitude of body observations, but *exact*
    > altitude of body does not seem to be critical.
    > Bill B
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