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    Re: Moon sight?
    From: Gary LaPook
    Date: 2014 Oct 4, 12:52 -0700
    And is the combined corrections in the Nautical Almanac moon correction tables easier to use than the separate corrections in the Air Almanac?

    Nautical Almanac tables require looking up two values and adding them to Ha if  a lower limb ,two steps, and an additional step of subtracting 30' if an upper limb, a  total of three steps.

    Using the Air Almanac tables requires three steps, refraction correction, semi-diameter correction, and P in A correction, also a total of just three steps!

    If using a bubble sextant, or if using a liquid artificial horizon and superimposing the images, the Nautical Almanac tables requires you to 1) look up the main correction and add it to Ha, 2) look up both of the corrections for the lower limb 3)and upper limb, 4)add them together and then 5) divide by two to determine their mean and then 6) add it to the Ha. Whew!

    If using a bubble sextant, or if using a liquid artificial horizon and superimposing the images, the Air Almanac tables requires you to do only two steps, refraction correction and P in A correction, no semi-diameter correction necessary because you have measured the altitude of the center of the moon.

    gl


    From: Gary LaPook <NoReply_LaPook@fer3.com>
    To: garylapook---.net
    Sent: Saturday, October 4, 2014 8:26 PM
    Subject: [NavList] Re: Moon sight?

    If using the NAUTICAL Almanac  moon correction tables, refraction and semi-diameter are already included in the correction tables.

    If using the AIR Almanac moon correction tables, refraction and semi-diameter are NOT included in the moon correction tables so must be applied separately. Using either almanac's correction tables should produce the same result.

    gl




    From: Samuel L <NoReply_SamuelL@fer3.com>
    To: garylapook---.net
    Sent: Saturday, October 4, 2014 5:36 PM
    Subject: [NavList] Re: Moon sight?

    Now you're confusing me.
    In a previous post you said- "That is all there is to it, you do NOT apply refraction or semi-diameter as these are already included in the corrections"
     




       
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