A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Michael Bradley
Date: 2016 May 6, 02:59 -0700
Beg leave to report a useful component available on ebay, Phot-R 40.5mm Circular polariser, costs 3.50 North Atlantic money.
It has a 1.5" circular polariser, rotatable, built into a slender circular frame. Fits into a 40.5 mm circular hole ( in home brew bespoke brass sheet shade frame ).
I've used it to replace the normal 'light' horizon shade on my Freiberger Yacht Sextant, and using it in the classic way to cut out reflected glare the horizon is much easier to resolve for morning and afternoon sunsights over water.
Excuse for doing it this way - my metal working skills with 2.5mm sheet brass are better that my non existent glass working skills. Also the case of a Yacht Sextant has very little space between the case side and the horizon shade, anything fatter would not fit. And it costs very little to build, cheaper than buying a sheet of polariser.
Result - water horizon glare reduction without buying a premium sextant.
Michael Bradley 55 North