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    Re: Sight Reduction Formula Question
    From: Paul Hirose
    Date: 2005 Jan 8, 23:00 -0800

    Bill wrote:
    > A lot for a liberal arts major to follow.  My question. Susan Howell states
    > (for the longer of the two formulas Fried gave) "if sin LHA is less than 0,
    > Zn = Z, if sin LHA is equal to or greater than 0, Zn = 360 - Z."
    I don't bother to compute Zn. A glance at the body's LHA reveals
    whether it's to the west or east, so I write something like Z = 55 W.
    To plot the LOP, rotate the protractor 55 degrees west of north.
    The procedure is the same south of the Equator, except that the
    protractor is rotated 55 degrees west of SOUTH, since Z is always
    measured from the "elevated pole".
    Maybe I'm just weird, but I find the above method easier than
    converting Z to Zn.

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