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Irv H., you wrote:

"Just joined into this topic. IF I understand your question ,the term is
called "Equal  Altitudes at Noon"."

The traditional technique of taking equal altitudes on either side of noon
has a couple of problems with it if it's used at sea. First, it depends
rather dramatically on the accuracy of each of those two sextant sights. By
multiplying sights, we can eliminate a lot of that error. The idea of the
method we've been talking about is to take a whole bunch of sights (10 or
12) around noon. Then you fit a curve to it (there are various methods
 --I've described one that works well but there may be a better way).
Unfortunately, if your vessel is in motion in the North-South direction, or
similarly if the Sun's declination is changing significantly (these are the
same thing --both change the distance between the observer's position and
the Sun's GP) then you need to correct for that. If you do "equal altitudes"
around noon without correcting for speed, you can be waaaay off. One way to
correct for speed is to find the time of LAN from the raw observations and
then do a calculation based on your speed (and latitude and the Sun's dec)
to correct the time. Another way is to adjust the raw sights by nudging them
up or down a bit based on a simple calculation (I personally recommend this
approach since it requires no special tables) and then you estimate LAN from
the adjusted sights.

And you added:
"This is NOT a fix per se but an E.P. (estimated position)."

You can get a fix using the procedure outlined (very roughly) above and
specified in more detail in earlier posts. If you mean it's only an
estimated fix, that is true of all fixes. Every fix has an error ellipse
around it.

 -FER



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