Do UV Filters Do A Good Job Blocking UV Light?

Setting aside the debate over whether filters should be used to protect
lenses, an interesting article on PhotoNet describes tests on several
different brands of UV filters to assess how effectively they actually block
UV, and the results are surprising:
"So if you buy a UV filter, you'd expect it to block UV right? Well,
sometimes you'd be wrong as the results of this test show. I've looked at
the range between 350nm and 400nm for UV blocking since the glass used in
almost all lenses will itself block any light with a wavelength shorter than
350nm, so you don't need help from a filter there."
http://www.photo.net/equipment/filters/

Jeremy

Re: Do UV Filters Do A Good Job Blocking UV Light?

I'm in the same camp as you. I have lenses that are wonderful, but that
have been out of production for decades, and it would be difficult to find
replacements in the used market that would be in as good condition as what I
already have. So I never take a lens out on a shoot without a UV on it. If
that means that I lose a bit of image quality, so be it.
I've discovered one additional benefit of using filters--the lens surface
remains free of fingerprints/dust/specks/windspray etc., making it
unnecessary to clean it more than once annually. And that serves to help
protect the multicoating on the front element from being worn away or
otherwise damaged. I am one of those clumsy guys that is forever smudging
the fronts of lenses with fingerprints. Now the filter can take the hit
rather than the front elements. I can replace filters a lot more easily
than lenses.
I try to take excellent care of my equipment and for me the use of
protective filters seems like the obvious thing to do.

Jeremy

Re: Do UV Filters Do A Good Job Blocking UV Light?

Excellent article. I have to go along with many who believe that UV
filters are a necessity. Thanks to some great advice on this
newsgroup, I use Nikon multicoated. It protects the lens from the
elements and the rubbing marks one gets when cleaning the lens.
Thanks for sharing the article.
Helen