NavList:
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Re: "Vernier acuity" of horizon IC tests
From: Greg Rudzinski
Date: 2009 Jul 8, 10:05 -0700
From: Greg Rudzinski
Date: 2009 Jul 8, 10:05 -0700
George, I find that my Pentax binoculars and camera lenses show superior images when compared to any of my sextant scopes. Sextant scopes may be compromised(intentionally?) in the areas of chromatic and spherical aberration. If so then I would hope for good reason and not to just save a nickel per unit on construction. Greg On Jul 7, 12:57�am, "George Huxtable"wrote: > Bill Morris reports an nice series of tests of index-error variation when > viewing a distant land-horizon.. > > To summarise > > naked-eye set 1: �mean error = 1.467; � SD = 0.458 > X4 Gal. � � � � � � � mean error = 0.743; � SD = 0.187 > X6 Kep. � � � � � � mean error = 0.593, � SD = 0.129 > naked-eye set 2: �mean error = 1.30; � �SD = 0.415 > > The surprise, to me, is not in the difference in the scatters, but in the > difference between the mean values of zero-error. > > Those statistics strongly suggest (though are not yet conclusive) that > there's a real difference between the index zeros, depending on the > telescope that's in use. If that's really the case, can anyone suggest a > possible physical cause? It eludes me. > > contact George Huxtable, at �geo...@hux.me.uk > or at +44 1865 820222 (from UK, 01865 820222) > or at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK. --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---