Previously written; Also, what's the real difference between a Skylight 1A and a UV? Is one more "clear" than the other?
A skylight has a faint reddish tint to it and blocks a little more into the visible blue spectrum. The UV has a faint straw color to it. Both have little effect on the visible spectrum and either can be used as a protective filter over a lens. There are also different intensities of the two. A skylight 1B and a UV-39 will block a bit more UV and blue light then their 1A and UV-37, but still not enough to noticeably affect the visible spectrum. I use SMC pentax L-39 (UV) on my lenses as I like the slightly darker skies it gives over 1a"s and UV-37's. Either Hoya or Tiffen include with their filters a little graph showing the wavelengths affected. Butch Each man had only one genuine vocation - to find the way to himself. Hermann Hesse (Demian)
