A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Greg Rudzinski
Date: 2016 May 6, 10:03 -0700
If two polarizers are screwed together with one polarizer filter flipped in the frame then you have a variable Sun shade. This is very useful at the index mirror when the sky is overcast, hazy, or partly cloudy. I filter this way when doing DSLR camera CN. I like older Vivitar linear polarizers best for this purpose. C&P uses polarizers stock on their current line of sextants.
From: Michael Bradley
Date: 2016 May 6, 02:59 -0700