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    Re: Moon's 4SD
    From: Bill B
    Date: 2006 Nov 08, 18:34 -0500

    Bill you wrote:
    > "Yes, and proved the eye, not sextant rigidity, was at fault."
    Frank replied;
    > Well, then get a proper prescription and a new set of glasses. Wear them when
    > you use your sextant. If you have serious astigmatism, there is no other
    > option.
    Working on it Frank.  I need to get the driver's license renewed this month
    if I can see well enough to find the BMV ;-)
    I have to admit, I hate eye glasses for cel nav with any amount of light
    pollution on land, as well as on the water in general unless absolutely
    necessary.  I will continue to try to determine an adjustment factor between
    vertical or horizontal sun IC vs. natural horizon IC's for sphere/horizon
    cel nav on the water.
    At this point I have a very accurate adjustment to Bowditch for distance off
    with objects of known height and bases below the horizon for my naked eye.
    I think with some effort I can come up with an IC for my naked eye between
    the larger sun IC and smaller horizon IC that will work for sun and moon on
    the water.  If my thinking is clear, stars should be able to use the horizon
    IC.  0.1' to 0.2' off on IC on the water in a light to medium displacement
    sail boat could be considered noise.
    I suspect for lunars there is no option for me but eye glasses.
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