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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Mirror artificial horizon finally working
From: Peter Monta
Date: 2014 Apr 24, 12:20 -0400
From: Peter Monta
Date: 2014 Apr 24, 12:20 -0400
Hi Alan,
Anyhow, I had the brilliant idea of trying theatrical lighting gell material, with which to make my own sun shields.
It might be good to verify that these are providing enough attenuation across the full UV/vis/near-IR bandwidth, in cooperation with whatever shades you're using on the sextant itself in the horizon-mirror path. I remember reading an article in Sky and Telescope some years back that mentioned several gotchas with using ad-hoc materials as solar filters. Color photographic film, for example, was said to be not nearly opaque enough in the IR and could be a real safety hazard. (Well, this particular material would be rarely encountered today, but the principle holds.)
Cheers,
Peter
Peter