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    Help with sun sights
    From: Patrick Goold
    Date: 2011 Jan 14, 12:06 -0500
    The sky has cleared over this part of the planet and I am trying to move on with my sun sights, taking sights before and after LAN as well as LAN, doing the sight reduction and plotting the LOPs.   One tiny wrinkle holds me up:  I do not understand the d-correction factor.  I have been going back and forth between Burch's Starpath course, Cunliffe's Celestial Navigation and Bowditch (2002) and this has worked reasonable well.  Where I hit a wall with one, I get a hand over it with one of the others.  But here I find no way opening.  Can someone explain this factor to me?

    Burch tells me "look to the bottom of the sun column in the NA to find the 'd-value' and record it..."  The number I find at the bottom of the page for Jan 13, 14 and 15 that has a small case d beside it is 0.4.  Is this what I need?  What do I do with this number?  How is it related to d-corr?  As for d-corr, I am unsure about how to read the increments and corrections table or what to do with the number I get there once I do.  Bowditch has a different way of talking about this, calling the d value a "d Correction Factor" and using it "to enter the corrections table".  This doesn't enlighten me. 

    I know there are people out there who take joy in battling back nescience and confusion about celnav.  Here is your chance.


    Dr. Patrick Goold
    Department of Philosophy
    Virginia Wesleyan College
    Norfolk, VA 23502
    757 455 3357

    Charles Olson: "Love the World -- and stay inside it."

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