LarsB

Hello Mooseman1007,

a Tiffen yellow #12 as barrier filter is indeed what you need.
Somebody also recommended me a #15 Wratten filter as an alternative.

However, there is a difference in the images you obtain with such glass filters and with plexiglas filters, e.g. those sold by http://www.nightsea....arrier-filters/
the former produce duller images which mainly only show reds and greens, whereas the latter produce brighter and more colorful images,
apparently because they "leak" a very tiny little bit of blue light.
The video mentioned above (http://picasaweb.goo...441065907391042) was made with such a glass filter.
See the difference with a plexiglas barrier filter in this video: https://picasaweb.go...504863416618418

Dear tubino,
dear Mooseman1007,

you can find some ideas on how to use existing torches and how to modify them for fluorescence diving here: http://guest.engelsc...ving/#Equipment

When using blue LEDs (450-460 nm), you need an additional excitation filter in front of your torch's lens from Rosco (Permacolor Glass Dichroic Filters) of the type "Medium Red Blue" #34600/#4600.

And of course a yellow filter in front of your mask and camera. I use those from NightSea: http://www.nightsea....hotoblue_ms.htm

You can also find a video of fluorescence diving in Dutch (cold!) waters here: http://guest.engelsc...ving/#Dreischor

Good luck!