Yellow and red filter for night dive light

[Aaron Lambright]

Hello.

I have just experienced my first two night dives and have a new passion! With my dive light, a Bigblue AL1200WP, I received a couple of filters, a red and a yellow. Can someone explain to me, in somewhat simple English, what one would use these filters for? I've tried good ole Google, but all I can find is what they do for photography. I'm sure it's rather similar but probably not the same for the human eye.

Thanks

 

[DiveClimbRide]

Hello.

I have just experienced my first two night dives and have a new passion! With my dive light, a Bigblue AL1200WP, I received a couple of filters, a red and a yellow. Can someone explain to me, in somewhat simple English, what one would use these filters for? I've tried good ole Google, but all I can find is what they do for photography. I'm sure it's rather similar but probably not the same for the human eye.

Thanks

Red light is better for fishes eyes, and less harsh on ours.

 

[Graeme Fraser]

Red light is better for fishes eyes, and less harsh on ours.

^^^this^^. Marine biologists, please correct me if I'm wrong, but some fish coat themselves in a protective mucus membrane at night to protect against predators. Under bright light they shed this layer and can't recoat, leaving them vulnerable.

Again, infrared (and to a lesser degree, red filter) doesn't adversely affect our night vision. Unlike the mega-lumen torches some divers wield like light Sabres.

 

[kevjli]

I night dive with a red spotting light. Fish don’t seem to see the red light very well compared to white light, so they don’t spook while you’re setting up your shot... especially for nocturnal animals My camera strobes put out white light when I actually take the shot, and that mostly overcomes the reddish tint from the spotting light. Often, the quick flash from the strobe doesn’t spook the animals either.

 

[Aaron Lambright]

Thank you!

It sounds like the yellow filter may be a bit of a compromise between the white light of my torch and the red tint of the fish-friendly red filter? To clarify, it is just a yellow filter, I am not using a blue light for fluorenes. My torch has power settings, too, to make things easier on the wildlife, which I intend to try out on my next dive. No sense blasting away at full power if I don't have to.

 

[kevjli]

I don't know how the yellow filter works. I do know that red helps to not spook nocturnal fish. I believe that the fish are not attuned to red wavelengths because the red wavelengths filter out of the water column pretty quickly as you descend. They just haven't needed to see red.

Note that when using a red light, you won't be able to discern things as well. Everything is reddish and kinda blends together... colors don't pop. I repeatedly switch between white and red on night dives. I use red to set up shots. My camera autofocuses just fine with red. The strobes mostly overcome the reddish tints on the photos. The filter on your Bigblue easily flips in and out, so you could do the same thing.

I dive in groups, with other divers that use only white lights (usually non--photographers), so there's some "ambient" light on the reef. When I'm on red, and further away from the group, it can be pretty dark.

I took this photo of a crab in Kauai last year. The group had been watching him with white lights and he was walk/running away. The group backed off for me and I hovered in front of him with a red light directly in his eyes. He stopped walking and I took some shots. The white strobes didn't seem to bother him because they're short duration.

 

[tursiops]

Hello.

I have just experienced my first two night dives and have a new passion! With my dive light, a Bigblue AL1200WP, I received a couple of filters, a red and a yellow. Can someone explain to me, in somewhat simple English, what one would use these filters for? I've tried good ole Google, but all I can find is what they do for photography. I'm sure it's rather similar but probably not the same for the human eye.

Thanks

It sounds like the yellow filter may be a bit of a compromise between the white light of my torch and the red tint of the fish-friendly red filter? To clarify, it is just a yellow filter, I am not using a blue light for fluorenes.

Your speculation about the yellow filter being for using a blue light is correct; that is really the only situation where the yellow filter will be valuable. The things that fluoresce are stimulated by U-V and blue light, the blue actually works a bit better. But then everything looks blue. So a yellow filter over your mask and/or your camera lens blocks the blue, and all you see is the fluorescence.

Some say the yellow filter on your light is better for u/w video.
https://www.scubaboard.com/community/threads/yellow-filter-on-dive-light.568770
https://www.scubaboard.com/community/threads/bigblue-vl2500p-red-light-yellow-filter.479969

 

[Newdiv]

Red light is better for fishes eyes, and less harsh on ours.

and ruins the sight for non-photographers, all you see is red. I hate being on a night dive with one of these lights around. I use a small light and cup my fingers over the lens and allow minimal light out.