
NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Raw data for bubble
From: Alexandre Eremenko
Date: 2007 Mar 07, 17:32 -0800
From: Alexandre Eremenko
Date: 2007 Mar 07, 17:32 -0800
Bill and Fred, Here I post some observations with my MkIXa bubble sextant. I will appreciate very much if someone who also practices bubble horizon observations will compare these data with his/her own. March 7, Sun alt. Without averager. Errors: 5.6, -0.6, -2.3 2.0, -1.4, -1.7, 0.6, -4.1, -1.7. Average error: -0.4, sigma=2.8. (Bill: this is a good example of how averaging works: the individual results are so-so (as shown by the sigma) but the average is excellent). March 7, Venus alt, with averager. Error 2.6. Without, errors: -3.0, 1.2, -1.9, -3.1, Average error -1.7, sigma=2. Febr. 20 Moon alt, with averager. Error 3.7. Without averager, error -1.6.a Febr. 20 Venus alt, without averager, errors 0.9, 1.9, -1.0, 0.1, -0.8, average 0.22, sigma 1.2 Febr. 20, Sun alt. with averager, error 0.3, Without averager: errors -3.5, -2.7, -3.4, -4.1, 0.0, -2.8. I will be very interested if someone compares these results with his/her own observations with bubble horizon. Especially interesting is to know the performance of Cassens-Plath bubble attachment. For its price (at Celestaire) one can have 10 or 15 aircraft sextants from e-bay, and surely several of them will work:-) And the weight is probably comparable (if you cut off the averager, of course:-) Alex. --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To unsubscribe, send email to NavList-unsubscribe@fer3.com -~----------~----~----~----~------~----~------~--~---