NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Greg Rudzinski
Date: 2019 Jan 7, 11:29 -0800
Joel,
Be sure that you are using the correct limb if not overlapping the Sun image. Try a liquid water horizon as a check to determine if there is a sight reduction error or a problem with the first surface artificial horizon and leveling.
Greg Rudzinski
'As a relative newcomer to celestial nav., I've experienced a puzzling problem. Using an artificial horizon, my sights at angles of 20 to 15 deg. (40 to 30 deg. sextant) have been significantly in error (40 min. to a full degree). Readings at greater angles have been relatively accurate.
My AH is a first surface miror mounted on a plastic cutting board. The board has three leveling feet and is leveled using a Starrett 98 level. The problem is evident with two different sextants.
Can anyone offer suggestions?