You say that's a black light filter? How does that work? Could it work with other lights or just the HID? No, just HID, and some LED's. Sounds interesting....I've seen black lights in aquariums for the same reason, bringing out the flourescent corals, but have never heard of taking one on a dive.
When I researched HID lights before buying one, I realized they use mercury to get the intensity, and being a UV chemist (my curing lamps are 20,000 watts @ $15K each) I knew they would throw out quite a bit of UV along with the visible light (I tested my Darkbuster HID, and it hardened my UV resins within seconds, proving high UV output). So remembering a Blue Planet special where they fluoresced corals in GBR with huge black lights that looked totally awesome, I decided to get a filter for my new HID, since it had a filter ring holder.
Googled and found Roscoe, a theatre lighting supplier, and bought two filters that were dichroic, (which allows 9% more UV passage than dark violet traditional Wood's Glass filters). They cost less than 50 bucks for both AND they cut them to the DIA that I spec'd.
Residual white light leaks around the ring obscured the subject a little, so I covered the filter ring holder with black rubber, and WOW what a show!
The results are far more dramatic than these photos and videos show.
So then I tested the filter at a local aquarium:
I finally made it to the FL Keys for a true test in the wild, and wild is an understatement (see above post for video, and more are on youtube under DrDichro).
Most corals fluoresce from green fluorescent protien (GFP), but many have both green and red and orange proteins which are awesome to consider that you are shooting a blue violet light, and all (dead) surfaces come back to your eye as blue violet til you hit some live coral, and you get colors you never would expect.
Some corals fluoresce both green and orange. I illumined a brain coral that was green in the ridges and orange in the furrows - waaaayy cool.
Other threads about my black light:
http://www.scubaboard.com/forums/ba...228530-biofluorescent-fun-your-hid-light.html
http://www.scubaboard.com/forums/in...cent-glowing-coral-videos-night-dive-2-a.html
You wanna get together for a night dive in May to see this light in action Doug?