< Since UV filters don't effect visible light, they don't
affect flare caused by a visible light source in the
frame.>
Any filter, UV, sky, or otherwise introduces two air-to-glass surfaces,
either of which can create or amplify flare. Flare is caused by light
bouncing off the surface of the glass (hence the benefit of multi-coating
which encourages transmission rather than reflectance), not by what kind of
glass you have.
regards,
Henry Posner/B&H Photo-Video
http://www.bhphotovideo.com
