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    Re: AM and PM time sights
    From: David C
    Date: 2016 Jun 29, 13:39 -0700

    Thanks for the replies.

    I had calculated Hc for both an assumed and my actual position. When I worked the time sight I mixed up the data. Using the correct data for my actual position in the time sight gave me a perfect result.  The two Sumner lines now cross at my location.

    I wanted to use the multi-latitude method because that was how Sumner discovered the position line.

    I now know how to reduce a time sight and plot Sumner lines. If I have problems in the future it will be a numerical error on my part.

    I will modify the t formula to account for same and contrary lat & dec.

    I have a brand new artificial horizon sitting beside me but when I look out of the window all I can see is an overcast sky.  Grrr!!!  Maybe I should use my spare time to can learn Ageton's method (-;


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