UV Index
I use an old D1X coverted to accept ir and uv by haveing a quartz plate put where the factorry fitted Low Pass Filter was in front of the sensor. Here are all my bodies the D1x can be seen top right. It has an old 50mm E lens which has had the surface coatings removed from the front element to enhance UV transmission. Also used, if not using sunlight, is the IR/UV flash gun - unfortunately these are no longer available from Nikon but alternatives are available (contact you local forensics science laboratory they may be able to say what they use).
In order to record a uv image the visible light must be excluded and a Hoya U-360 will do this ( the flash has a UV filter that clips over).
The U360 however passes a little ir which needs filtering out and so a Schott 39 filter is used as well.
Obviously there is a spectrum of uv just as visible but our eyes do not see it so the different frequencies can be coloured as ones own choice here is a uv photo of Yew Tree Tarn near Coniston Water in the Lake District. Camera light meters cannot "see" uv so I have had to make the one shown below.
