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    Re: Noonsite using artificial horizon? Did I do it correctly?
    From: Samuel L
    Date: 2014 Aug 27, 06:05 -0700


    I'm getting a little better at taking a noon sight.

    I've read at length the replies concerning using an AH and using an Upper Limb or Lower Limb observation....but am still confused.

    Now I take the Lower Limb of the Sun and put it tangent to the Upper Limb of the reflected Sun from my AH.

    What correction do I apply in that case?

    I found this- http://astro.ukho.gov.uk/data/na2003/bookmark03.pdf

    ....which mentions UL and LL in the Apparent Altitude columns.

    Do I use that?

    Or....per the serveral other posts about this topic, do I simply subtract Refraction and continue onwards with the other calculations like this?

    Here are the steps I use

    1- Measured Altitude at LAN

    2- +/- Index Error

    3- Result= Hs

    4- Subtract Refraction

    5- Result= Ho

    6- Subtract Ho from 90 D

    7- The result is Zenith Distance

    8- Add Declination (assuming it's "Same name")

    9- Result= Latitude at LAN


    Thanks again,



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