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Re: Bris Sextant pictures
From: Alexandre Eremenko
Date: 2005 Nov 4, 17:22 -0500
From: Alexandre Eremenko
Date: 2005 Nov 4, 17:22 -0500
George, This is an interesting idea: On Fri, 4 Nov 2005, George Huxtable wrote: > Another question. Can you improve the accuracy achievable with such a > device, by holding it (or strapping it with sticky-tape) in front of the > objective of a sextant's telescope? Or any other telescope or monocular. I think it is worth trying. The thing which worries me is safety. Bris "sextant" is so small that it will not cover the objective lens of any telescope, and it is absolutely necessary to cover the whole of it when you look at the Sun. Essentially my proposal would be to make an attachment to the telescope in the form of a larger (round?) Bris sextant which can be attached in front of the objective lens. Or to make a square hole in the usual objective lens cover and fill the hole with the Bris sext. This certainly should improve precision. (I had too few observations to make reliable statistics, but it seems to me that my observations with Bris have similar precision to my observations with ordinary sextant without a scope. (I made several observations without scope being unable to keep the Sun and the horizon in the field of view during rough weather)). Alex.