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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Greg Rudzinski
Date: 2018 Aug 3, 10:55 -0700
Several different Bris Sextant projects have been completed and tested this summer with some new findings regarding construction. The first finding was that there is quite a difference in quality between microscope slide brands. The best brand so far out of five is AmScope BS-50P. The next and most important finding is the use of UV activated resin as an adhesive. Very sturdy ! Just don't make any mistakes with it. Undoing will require a razor blade and or acetone. The final finding is that high altitude Bris Sextants are hard to construct and under perform in testing. The limit seems to be 52° using a 4mm shim for the camera models. When used on a DSLR camera best results were achieved with a wide angle 35mm lens, f16, infinite focus, manual mode.
Greg Rudzinski