A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Richard MacCormac
Date: 2020 Dec 3, 03:59 -0800
Can you help me out? I'm really close with this right up to the SD & refraction step (same pixel-counting technique as Bill, and my Hs came out at 1 41.05'). Cleary the SD is 16.2', so it looks like your refraction figure is 35.1'-16.2'=18.9'. Going into the table at Sight Corrections (navsoft.com), I've been pulling out 19.8' (next to the Ha of 1 41'). That puts my intercept a mile or so further away than yours. Not much, but enough to find out what I'm not getting right. As that's where my error is, can you explain how you arrive at your 35.1 SD+ref figure?