A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Modris Fersters
Date: 2021 Jul 27, 11:58 -0700
Thank you for posting your results. Your sextant practically is not affected by tilt of the instrument (contrary to mine). The difference 0,1 minute of arc is fully acceptable.
But I can not understand why your sextant makes 0,3 minutes error in measured angle. On 26 July the Suns SD is 15,75. That means: the correct result for 4SD would be 15,75*4=63. Your first set gives results 4SD=63,24 (60-38,4+41,64=63,24), and the second set: 4SD=63,36 (60-38,44+41,8=63,36). Or on average: your measured angle was (63,24+63,36)/2=63,3. Have you any idea why the error is so large while your individual measurments are in range +-0,1 minute of arc.