Please recommend a light to shine through water in a lake?

[Kaban]

Would you guys consider the Surefire UB3T Invictus an aspherical light?

It has a very distinct optic but I am not sure if it's technically aspherical. Would it work for what I am looking for? (P.S I wanna get that light either way so if it works well for this, it would just be an added bonus).

 

[EscapeVelocity]

Polarising sunglasses allow you to see into water because they stop light that's been REFLECTED off the surface.

There's no benefit in aiming polarised light at the surface - if you get the angle wrong, all you'll do is reduce the light getting into the water.

Right. That is why you cut it out and place it front on the lens, then rotate it, for best orientation when using. But the glasses are an easier and better solution.

 

[EscapeVelocity]

I think the problem of using a flashlight to illuminate through water is not unlike trying to use a flashlight to illuminate the outdoors through a window. With any flashlight that has spill, all you see is the backscatter light/glare. Nothing can be seen outside, even if it might be illuminated. What works is a light reduced to a small circle. Such as seen with an aspherical flashlight. There is still backscatter but it's not nearly as much and the light clearly illuminated a spot 40 plus yards outdoors that could be easily seen through the window.

The Brinkman Q light is not designed to illuminate fish in the water. However, it would be better than a standard searchlight without the blue tinted front end. You can turn a Brinkman into a pretty good spotlight by placing a long tube (called a snoot) over the front end.

Itls only partially blue tinted around the edges to tighten the beam and reduce backscatter. It is also frosted in the center of the lens to do the same. While a snoot may help, the Brinkman is already addressing the issue.

 

[EscapeVelocity]

Would you guys consider the Surefire UB3T Invictus an aspherical light?

It has a very distinct optic but I am not sure if it's technically aspherical. Would it work for what I am looking for? (P.S I wanna get that light either way so if it works well for this, it would just be an added bonus).

I dont know about that particular model, but the cheap focusable cree flashlights will focus to a sharp rendition of the square outline of the LED emitters. I have a cheap headlamp like that. Then it's just a matter of getting a unit with large enough battery capacity, or carrying spare rechargeables.

 

[DTF]

Got a Dereelight XSearcher (to go along with the Night Master I already have) plus a green emitter pill on the way. Once it arrives, will see what it can do to take a peek into the Willamette.

Blue emitters seem to be a lot less common than the green. The only aspheric lens model that I can find available with a cyan emitter is the Night Hunter. Cyan version not listed on the US distributors web but is on the mfg website. Have put in a request for a quote on getting one.

 

[AnAppleSnail]

Most of this discussion about glare is moot with an aspheric. Unless you are shining the aspheric at your feet (Directly under the dock) there will be no glare except in very rough water. The light will mostly penetrate or reflect away from the water at an angle.

Kaban, I suggest that the best bang for your buck will be two cheap "Flood to Throw" lights with decent rechargeable batteries (NOT 3xAAA). Your assistant should use one, and at some point swap batteries in the previous one. This will run you about $25 for two of them using RCR123 or 18650, about $15 for a charger, and about $10 per cell because you should get quality cells (And enough for the runtime to last). That's going to be about $60 for a system that'll last about 4 hours without stopping to recharge.

These won't have high lumen output, but they WILL put light where you want it. I actually suggest that you shy away from the ones with super high output (over 300 lumens) because they aren't optimized for your task.

 

[VidPro]

when the assistant holds it that would fix some of the issues of back glare (keylight), and the aspheric will send out a more lazer like beam.

But i have to disagree with Blue, i stood right there testing colors. With my 12W RGB light I stood over the creek out here for hours, shooting down to the fish, who frankly didnt care what light was hitting around them or what color it was till I shot the laser down.
The blue color was the worst of the bunch for causing glare on the top of that creek, the green and the red would pass the top easier. now maby it had to do with how my eyes were reacting and all, but i tested it over and again, and blue made that blinding haze on the top of the water.

Sure blue is the last thing that makes it down the depths of water, and sure the moisture in the atmosphere breaks up the blue all over the place, and that is why we see a blue sky? But when trying to get past the Skin on waters, it sure seems to me like blue is the wurst thing.

why is the sky blue? because yellow gets filtered out? or because blue gets reflected (scattered) up there in the moisture? Isnt it true that the light we are usually seeing is "reflected" off of surfaces? Filtering yellow, means we are getting more blue on the ground. Reflecting (scattering) blue, means were seeing more blue Up there? And up there further again, nasa

I have heard the blue theory before, it never made a lot of sence to me, so I stood there testing it. Unless I have some odd color sensitivitys from living under (bluish) Leds

Saw the same basic thing when at the Get-Together the high blue lights (like hid) would light up the top of the resivoir we were at, but the incans, would shine through about 2-3feet of water. (we were above the water by many many feet) . I think everyone else just saw how powerfull looking the Blue beam was , as it lights up the air and the top of the water OOhhh bright. Being an hiker i was instead trying to see the landscape and features.

I would totally agree that unless you shove the light IN the water, your not going to get a distance, and in "bay" type water, you cant get really far, mabey seeing a glint off the scales on a rainbow trout at 6 feet, if there is no moon. But the Blue, I wish someone else would test that, using all the colors , because for me the blue has been the bane in all water skin situations. It is always comming back into my face off of water.

Lets go deeper, your in deep water, scuba even. the blue makes it down through the water, ok i totally agree, But if all the light is blue under there why would i want to bring a blue light ? If i wanted to see something amidst all that blue, putting a bit more spectrum back, might just be better than beeming more blue through.

I am just saying What are we trying to achieve , a cool beamshot of the light? or being able to distinguish features past all the blue.

 

[TEEJ]

Would you guys consider the Surefire UB3T Invictus an aspherical light?

It has a very distinct optic but I am not sure if it's technically aspherical. Would it work for what I am looking for? (P.S I wanna get that light either way so if it works well for this, it would just be an added bonus).

No, its TIR.

As I mentioned, wearing polarizing glasses that are not tinted would cut the surface glare better.

 

[VidPro]

I just tested polarization, at night with flashlights.
The creek is rather calm, so it was hard to get reflections at different angles. Aparentally none of the light , the leds (until using linear diffusion) florescent or incan, or even the sun, is outputting polarised light originally/normally. It is the angle that it hits a reflective plane that polarises it. (as if i can explain it).

http://www.edmundoptics.com/learnin...ion/successful-light-polarization-techniques/
""Incandescent, fluorescent, LED, and many laser light sources are randomly polarized""

http://www.polarization.com/water/water.html
""Maximum polarization is obtained when the sun is at about 37 degrees from the
horizon (in theory 100% polarization at the Brewster angle). If the sun is very
low or very high the sunglasses will be of little help in filtering the glare in
calm seas. A rule of thumb would be that polarized filters limit the glare from
calm waters for a sun altitude between 30 and 60 degrees.""

I guess I couldnt get an angle worked out, especially without an assistant, and the dog didn't qualify
If you shoot straight down, you wont get "horizontally oriented reflections" like the sun provides at angle, that the polarised lenses try to block. Twist and turn, change angle , no change in visability.

At night the lake around here also would be calm, so it would be hard to test for that type of reflection (need waves).
Because polarising the light would polarise all of it, I dont think that would change anything.
(Pier fishing would have more waves, I didnt test that)

I was so confused, I had to come back and test the glasses again to see if they were polarized. Out there, twisting around all kind of angles and not much happened, except on the streets reflective signs and markers. Because as we all know when the sun is out, cutting that specific glare , allows you to see right into the water. (the fishermans glasses) With my artificial light, and calm seas, I would have to have that kind of polarized glare , for it to help.


side notes: I had the china blue led, and a "warm" led light. The bluish one, still put up that haze on top of the water. The warm Led still does not have far red like an incan, but it was "better" than the bluish one. And I scared the fish a bit this time with the aspheric blast.

 

[EscapeVelocity]

Thanks, VidPro

 

[jh333233]

Please be reminded that water is semi-transparent to light, meaning only a small portion of light is getting reflected to your eyes
Explicitly, you will need more throw/lux to light up the surface of water compared with a wall or anything solid
Like what we flashaholics love to do, shining a beam over the sky and watch the light ray

 

[VidPro]

Would this work?
A sealed beam headlight , not halogen, the old all sealed incan thick glass sealed light. 15-20 feet of low voltage landscaping cord , because it is thick guage so there will be minimal losses. Wire it onto the end which they had hearty screw connection on them. nothing else, the 12v wont do much electrolisis in a lake (bulbs raw connections). And the wire itself is insulated. Any extra sealing would mean you would have to put the whole thing in a box.

Lower it down into the water before you turn it on. because offset temperatures on the glass will shatter the glass. Turn it off before bringing it out of the water.
It would then act like a Pool light. It would light a fairly wide swath, and you could have high beam low beam and both driven at the same time for a variation in output. Run it off a big 12V source.

http://newsletter.1aauto.com/articles/headlight/sealed_beam_headlight.jpg
(some picture off the web of a sealed beam headlight)
The old school sealed beam headlights were a whole "bulb" item manufactured with reflector and diffusion,not an assembly of seperated parts, the glass was thick, the suspended filament is not very close to the glass.

To keep thick glass from cracking the temperature all around it would need to be similar always, so it is only on submerged fully by the water, or only after fully dry again on the land. Would not be for salt water, or partly salt water, only for lake water. For salt water the least would be to silicon seal all the metal on the connections and exposed wire places. Weighting it so it sinks at the angle desired.

A pool light can be low voltage or ac voltages, and being more specialty require sealing, and could cost way to much, this stupid method would costs less than $50 . At greater depths the water pressure issues would have to be figured.

Check local fishing regulations. for Missouri example:
""As an aid to fishing methods, an artificial light may be used only above the water surface. However, while fishing by pole and line only, underwater lights may be used to attract fish. Underwater lights also may be used when bowfishing on lakes, ponds and other impoundments.""