A while ago I tested it against the Coastal Optics Micro Apo 105mm and the Nikon UV Nikkor 105mm and it perfomed very well.
[click on image gets you a larger image]
The spectrometric results in comparison to the Kuribayashi 3.5/35mm lens, one of the best performing "normal" lenses for UV reveals that is very useful for reflected UV:
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The B&L lens has a very high UV performance, at 365nm it transmits 74%, whereas the Kuribayashi has 80%, so very close to it. A very useful long focal length lens for reflected UV with quite high UV transmission and reaching rather deep into the UV range for a non quartz fluorite lens.
So and here a few shots I took the other day with it, first the roof of the neighbour house about 20 meters away:
Then a Rudbeckia hirta flower on my balcony from about 4 meters away:
It is indeed a rather sharp lens for reflected UV, which allows a nice working distance, if so needed. A good addition to the rare tools for reflected photography!
I have written HERE more about it.
Stay tuned, more will follow on that fascinating subject...
More info on this very interesting field may be found on my site http://www.pbase.com/kds315/uv_photos