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    Re: Lunars with SNO-T
    From: Alexandre Eremenko
    Date: 2004 Oct 24, 03:14 -0500

    On Sun, 24 Oct 2004, Frank Reed wrote:
    > Second, nice job! I maintain that lunars are NOT
    > difficult if you have a
    > reasonably good sextant with a very good telescope
    I still have to learn to reduce them "by hands" without
    your web site. I think I understand the theory well
    enough (from Chauvenet). It remains to organize the computation.
    First on my computer and then by hands.
    > you get
    > some practice
    > with sight accuracy (such as the ones you've been posting on).
    Following your advise, I practiced with star-to-star a lot.
    Contrary to my a priori expectation this was harder than
    taking the Sun. I cannot explain why. (My very first LAN
    observation gave latitude only 0.1' off. But with stars
    I had to practice).
    > And:
    > "Comments: 1. NOW I finally understand what
    > the cross-wires in the scope are
    > for."
    Well, I did not say they are necessary, but they help.
    They help to keep the picture at the center of your field
    of view when you sit in an awkward position, holding the
    sextant "handle up".  My hand is just trembling enormously
    in this position. Next time I will try to do the trick
    with Galileo scope.
    > Once you have things lined up,
    > you can often find a more comfortable pose by
    > flipping the sextant over.
    I followed the advise to look at the star straight,
    having the Moon in the index mirror. This determines the
    position of the sextant. Holding it up side down
    (that is telescope aimed at the Moon) makes it almost
    impossible to catch the star (there are so many around!)
    But now I understand that when the Moon and the star almost touch,
    I can try to invert the sextant to get precise touching.

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