NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Greg Rudzinski
Date: 2012 Apr 20, 11:37 -0700
[NavList] 11 body sight run, all under 4 miles! Love this instrument!
Randall,
You have discovered the virtues of a metal sextant :)
Check on that Denebola observation. A 3NM discrepancy from a known position verified by chart or GPS is the point where I suspect an error somewhere in the CN observation, reduction, and plot process. Most of my discovered errors are the results of misreading the sextant, watch, or table look-ups. Transposing azimuths and plotting off the wrong assumed position are also regular mistakes :( Not rushing any phase of the process seems to reduce the frequency of errors.
Good job on this round of stars !
A certain amount of error will just be the natural personal deviation from the mean. For me the max. expected deviation from the mean is plus or minus 0.5' moa and also comes into play when determining index error using the natural horizon as reference. This is one of the reasons I don't try to adjust out the last 0.5' moa of index error on the sextant horizon mirror.
Greg Rudzinski
From: Randall Morrow
Date: 20 Apr 2012 07:59
April 17/2012 Tax Day star sight results
Date 4/16/12 PM GPS 35* 19.5 N, 119*05.5 W
Body Time Hs (AH) Ho Hc (USNO) a
Procyon 8-46-37 99*14.4 49*36.4 49*37.7 1.7T
Sirius 8-48-26 47*33.0 23*44.2 23*43.6 0.6T
Rigel 8-52-25 27*16.0 13*34.1 13*33.4 0.7 A
Venus 8-56-13 50*54.2 25*25.5 25*24.6 0.9 T
Capella 8-57-23 78*2924 39*13.5 39*14.4 0.9 A
Alkaid 9-01-54 90*57.6 45*27.8 45*27.3 0.5 T
Arcturus 9-03-24 61*01.4 30*29.1 30*29.8 0.7 A
Elnath 9-06-31 67*03.0 33*30.0 33*28.5 1.5 T
Denebola 9-12-22 116*36.6 58*17.7 58*13.9 3.8 T
Saturn 9-14-11 47*16.6 23*36.1 23*37.5 1.4 A
Spica 9-15-34 47*25.2 23*40.4 23*42.2 1.8 A
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