Today a spectrometric test using that previously mentioned Petri Kuribayashi f3.5/35mm lens, compared to a Kyoei Acall f3.5/180mm lens in M42 thread mount, as a proof that both actually have a very different lens transmission, especially in UV.
[click on image to see a larger one]
The Kuribayashi 35mm reaches much deeper into UV, even a bit below 320nm and shows a rather high UV at 365nm transmission of over 75%. However the Kyoei Acall f3.5/180mm tele lens seems to be a very different beast, as it has no useful at all UV transmission!
I have written about that lens before HERE
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