Light Question

[PerroneFord]

I think if the DM had suggested a lower wattage light for all the very good reasons you list, the original poster would likely not have put this here. To fabricate a lie to the light owner and ban his light was asinine.

I see the original poster has edited the language in his post. Not sure why.

 

[*Floater*]

I think bright lights do bother fish and other creatures at night. I used to have an overvolted 50W halogen and some of the underwater creatures would try to scramble away from the beam. For example, when I shined it onto a school of small fish at night they'd start to act funny, making weird turns, breaking formation, etc. They didn't like it.

 

[bperrybap]

Hello occrider,

I also agree with Manta and PerroneFord, HID’s are bright but not brighter than the sun.

I disagree with this.

I think its not really a question as to which is brighter but rather
which casts a more intense light on the sealife.
I'd be willing to bet that if you took a light
meter down and took a measurement on the reef on a very
bright sunny day and then took a reading at that very same point
at night when a bright HID light was shining on it,
that the HID light would measure more Lumens than the sun.
Especially, if you were down below say 40 ft.


--- bill

 

[PARADISE HUNTER]

The edit I made to the original post was just a gramar correction. No other posts had been made prior to it.

My concern is less with the DM and more with the issue of light damage to the underwater life. I am glad I posted the question. There seems to be some varying opinions and good information.

 

[jfoster33702]

FYI, I have a saltwater tank and I have 400w of metal halide lighting about 12inches from the corals.

If you want to go 100% purist - any articifial lighting introduced during the reefs natural, nocturnal cycle is going to do more harm than good...

Everything in moderation - right?

Jeff

 

[TSandM]

I don't think dive lights do any damage, but I'll tell you that my experience with a 21W HID on a night dive in the tropics was that it was WAY too much light. I had much more fun, and saw more nocturnal animals, using a small penlight-type dive light in Hawaii. I would not take the light saber down for that kind of dive again.

 

[MXGratefulDiver]

I don't think dive lights do any damage, but I'll tell you that my experience with a 21W HID on a night dive in the tropics was that it was WAY too much light. I had much more fun, and saw more nocturnal animals, using a small penlight-type dive light in Hawaii. I would not take the light saber down for that kind of dive again.

That's why I take the NiteRider to the tropics ... there's where that wide-angle beam serves you very well indeed ...

... Bob (Grateful Diver)

 

[Metalsub USA]

I don't think dive lights do any damage, but I'll tell you that my experience with a 21W HID on a night dive in the tropics was that it was WAY too much light. I had much more fun, and saw more nocturnal animals, using a small penlight-type dive light in Hawaii. I would not take the light saber down for that kind of dive again.

This is exactly why I recommend using a floodlight reflector (or if you have a adjustable beam, the widest setting) on night dives. Instead of having a light saber you have a wide cone of lower light intensity. My original post clearly advocates using a flood light.

 

[TSandM]

I actually USED the light on widest dispersion . . . I lit up an area the size of a two-car garage!

 

[Damselfish]

A bright light close to something is certainly brighter than sunlight underwater. I've certainly heard DMs in the tropics say you can injure or burn things, I don't know if this is true. But it's pretty clear from behavior that some of the stuff out at night, the stuff you're presumably there to see, isn't pleased by bright lights. Except of course the ones using them to hunt by...

I just can't see turning a night dive into a day dive.