NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: EBBCO/filters
From: Peter Fogg
Date: 2007 Nov 22, 13:31 +1100
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From: Peter Fogg
Date: 2007 Nov 22, 13:31 +1100
Isonomia wrote:
> My concern with using two polarising filters is that the UV may behave
> differently and not be polarised, so although the optical light is
> diminished, the UV comes through just as before!
Hmm. My understanding is that a thin sheet of plain old ordinary transparent glass is quite an effective UV filter - and that UV filters made for use in front of camera lenses consist of little (if anything) else!
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