A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Position-Finding
From: Greg Rudzinski
Date: 2016 Nov 30, 09:07 -0800
With ex-meridian calculations only 3 place accuracy is needed for 0.1' accuracy by formula so a 10" slide rule is good enough. The limit to accuracy is meridian angle. The smaller the angle the smaller and more accurate the resulting ex-meridian correction. I like to keep the meridian angle below 7°. Another factor to keep in mind is the altitude of the observation. The lower the better.