A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Brad Morris
Date: 2015 May 10, 21:41 -0400
Superimposing the sun's image onto itself or the moon's image onto itself is a highly effective method of determining the index error.
Just watch that you don't blind yourself by observing the sun without shades! That pain you feel in your eye is a warning! (Slight humor should be noticed here!)
Thanks for the info.
There is no free sight around possible in the backyard. It is dark now, so I used Venus, that works. The index error is now back from 55' to zero, as long as it stays with a plastic sextant. Is a high cloud with a sharp edge usable for index error? This is just an idea, as nothing else is possible?
Frank can you explain: What is the Sun test on the Moon?