A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Henry Halboth
Date: 2014 Aug 27, 13:44 -0400
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