UV Dive light

[ggunn]

If it doesn't have a physical filter (which from context I assume it doesn't) and munges the image digitally, it's neither and a bit of both. Digital filtering is voodoo.

 

[NDL_Diver]

I disagree. If this were the case, you would have a super saturated photo. From what I have read, it does not add color but filters out the blue.

Correct, Red filters out Cyan, not true blue that is why it is use in Caribbean waters and Magenta in Turquose green water.

Color wheel from Color Wheels are wrong? How color vision actually works

 

[NDL_Diver]

ALSO adding a filter at depth reduces the brightness of the photo and thus you need to decrease your f stop or shutter speed.

FILTERS by definition filter, they don't add.

Also why you use a Yellow filter with some UV lights to reduce Blue.

edit: To reduce/eliminate Cyan color light you go 180 deg from that color on the wheel and that would be a Red filter. By filtering out Cyan from white light you are given an appearance of Red because you reduced the color cyan from white spectrum.

 

[DandyDon]

We're way above my pay grade now.