BEx filter 500

Fluorescence Excitation Filters

NIGHTSEA’s fluorescence excitation filters turn your electronic flash into a source of intense blue light for taking fluorescence photographs. The key element is our custom made interference filter that transmits just the blue light you need for underwater fluorescence photography. They are used in conjunction with a barrier filter in front of your camera to record the vibrant images you see in the photo galleries.

You can even take fluorescence photographs in the daytime – with a short shutter speed you can underexpose the ambient light without affecting the fluorescence image.

NIGHTSEA offers a variety of excitation filters for underwater use:

  • EX-Z330 – specially designed to mount on the Inon Z-330 strobe. The filter has a bayonet mount to the front of the flash, the same way that the diffuser supplied with the flash attaches.


  • EX-INON – specially designed to mount on the Inon Z240 and D2000 strobes. The filter attaches directly to the threaded holes that are provided for the Inon diffuser.  By loosening the thumbscrew you can easily rotate the filter out of the way for switching back to white-light photography.


  • EX-YSD1 – specially designed to mount on the Sea & Sea YS-D1 strobe, and also compatible with the YS-D2. The filter slips smoothly over the front of the strobe and secures with plastic thumbscrews.
Excitation filter for Sea&Sea YS-D1 flash

Excitation filter for Sea&Sea YS-D1 flash


  • EX-YS250 – specially designed to mount on the Sea & Sea YS-250 strobe. The filter has a bayonet mount that attaches directly to the front of the flash for easy installation and removal.
EX-YS250 mounted

EX-YS250 mounted


  • BE series – general purpose filter designs that fit over the face of a strobe, with an elastic strap for attachment. (Can also be used over high intensity lights such as the Underwater Kinetics Light Cannon and others to convert them into fluorescence excitation sources.) Available in three diameters:
    • BE1 for up to 82.5mm (3.25″)
    • BE3 for up to 101.6mm (4″) (e.g., Ikelite DS160, DS161)
    • BE5 for up to 127.0mm (5″)
BE series excitation filter

BE series excitation filter

All of the underwater excitation filters are priced at $189.00. You can purchase them direct from NIGHTSEA or at Backscatter Underwater Video & Photo. (If you are purchasing only photographic accessories please make your purchase on the Backscatter site.)