A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Position-Finding
From: Frank Reed
Date: 2017 Oct 7, 09:54 -0700
Hien, you wrote:
" Now the only thing that left is recalibrating to get rid of the index mirror and the side mirror."
Hmm... Maybe you should just leave it as is then! Index error is fully measurable and correctable, and side "error" actually is no error at all. Perhaps it's time to get some data. Take a dozen Sun sights spread over a nice range of altitudes and record the exact time and location for each sight. Post your data here, and we should be able to assess how well the sextant is performing. One question: are you able to adjust perpendicularity of the index mirror? That does matter.