NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Herman Dekker
Date: 2019 Jul 10, 09:15 -0700
Frank, thank you for the explanation.
I had to degrade to this method, because this week when, for the first time, I tried to shoot a lunar, but my stiff neck gave problems.
I could see the sun at ~60° hight with pain in the neck, so I quitted. I know now why I love the A-12 bubble sextant, for sun and moon
you can look down without neckpain. So have to degrade to Lunar altitudes.
Forget old Rule: Moon should be near the prime vertical
Correct Rule to remember:
The moon horns must be horizontal or max 45° tilted from the horizontal.
(I believe I have never seen horizontal horns, on my latitude 52°N, but at home only Altitudes above 10° are visible)
But what with a full moon? Is it usefull on xx:00 hour to Precompute Moons Hc1 and again say xx:15 hour for Moons Hc2.
Subtract Hc2 from Hc1 and divide the answer bij 15, this gives the change in altitude per minute.
Again question rises what is minimum alt/min change for resonabele result on my Latitude 52°N?
Well next days are forecasted cloudy, so have to wait for a trial.
regards
HermanD. 52°N 04°E