Electroluminescence Sticks

[+EScout]

Krill lights

Just ordered a bunch of these for my geocaching, ham radio, disaster communications type friends. (to get the big discount)

 

You can drop on concrete, last for days on a set of batteries, preserve night vision (activates rods vs cones in eyes). All together, irresistable for the gadget lover. Check it out.

[+Prime Suspect]

Krill lights

Just ordered a bunch of these for my geocaching, ham radio, disaster communications type friends. (to get the big discount)

 

You can drop on concrete, last for days on a set of batteries, preserve night vision (activates rods vs cones in eyes). All together, irresistable for the gadget lover. Check it out.

Most interesting on their website was what they didn't say. There's nothing mentioned about the fatigue effect of electroluminescence lighting (i.e. the light output isn't constant, and will grow dimmer over time, even if the voltage remains constant).

[+GeckoGeek]

Krill lights

From the web page:

Night vision compatible.  The light produced is soft and complements human night vision by stimulating the rods in your eyes.  In contrast, the light from a flashlight stimulates the cones in your eye resulting in "night blindness" when you look away from the flashlight's illuminated area or turn it off.

 

Do tell how that works - especially when they have different color models? The best I can think of is it's a fancy way of saying they are too dim to give you night blindness.

Edited December 18, 2003 by GeckoGeek

[+Navdog]

Most interesting on their website was what they didn't say. There's nothing mentioned about the fatigue effect of electroluminescence lighting (i.e. the light output isn't constant, and will grow dimmer over time, even if the voltage remains constant).

This page has a chart that shows the light output, compared to cyalume, as much higher and fairly steady out to 40 hours. If true that's pretty impressive.

 

Fifty hour burn time on 2 AA batteries and 3000 hr. lamp (phosphor) life. Sounds pretty good too.

[+Prime Suspect]

Most interesting on their website was what they didn't say. There's nothing mentioned about the fatigue effect of electroluminescence lighting (i.e. the light output isn't constant, and will grow dimmer over time, even if the voltage remains constant).

This page has a chart that shows the light output, compared to cyalume, as much higher and fairly steady out to 40 hours. If true that's pretty impressive.

 

Fifty hour burn time on 2 AA batteries and 3000 hr. lamp (phosphor) life. Sounds pretty good too.

Those are just luminance times. That has nothing to do with electroluminescence fatigue, which is a long term effect (and which a fresh set of batteries won't cure).

[+Team GPSaxophone]

Those look cool. I may have to order some!

[+EScout]

Prime Suspect:

If you have factual data on the fatigue and its rate, please provide it. If it is gradual and over many hours, this would be a minor factor. And at a price of about $20 (about $17 in the quantity just ordered), the advantages would seem to outway this negative. Advantages being: water proof, drop on concrete proof, long battery life, long element life, small size, uses standard AA batteries, night vision enhancing.

[+Fatboy Slim & Rainey Belle]

Krill lights

From the web page:

Night vision compatible.  The light produced is soft and complements human night vision by stimulating the rods in your eyes.  In contrast, the light from a flashlight stimulates the cones in your eye resulting in "night blindness" when you look away from the flashlight's illuminated area or turn it off.

 

Do tell how that works - especially when they have different color models? The best I can think of is it's a fancy way of saying they are too dim to give you night blindness.

Yours eyes have two "recievers" that are stimulated by light and send messages to your brain. RODS are stimulated by colored light and CONES are stimulated by white light. When the light source is colored, everything reflects colored light, and leaving your CONES pretty much in their lower stimulated state. So that you still have "night vision" when you look away.

 

The military and others have been using this knowlege for years. ie, the red light in an aircraft cockpit, or the red lense cover for army flashlights.

[+nincehelser]

Yours eyes have two "recievers" that are stimulated by light and send messages to your brain. RODS are stimulated by colored light and CONES are stimulated by white light. When the light source is colored, everything reflects colored light, and leaving your CONES pretty much in their lower stimulated state. So that you still have "night vision" when you look away.

 

The military and others have been using this knowlege for years. ie, the red light in an aircraft cockpit, or the red lense cover for army flashlights.

Actually, it's the rods that are most light sensitive, but monochromatic. The cones are what actually detect color.

 

You can see this difference easily if you're a star gazer. If you look directly at a faint stellar object, you won't be able to see it, but if you look off to its side, it will be brighter and more visible....it's commonly called "averted vision". It's because it causes the image to fall more toward the sides of your eye, were the light sensitive rods are more common. Cones are concentrated more in the center.

 

Then there's the whole issue of your pupil. Red light doesn't cause your pupil to contract like other light, thus allowing more of the available light to enter. Pupil size is probably the bigger factor in night vision.

 

George

[Bender]

It seems to me that EL type light is usually rated by how many hours it takes them to get to half brightness (as in the "bulb" "wearing" out). I think I read that somewhere once. But then again, I could be wrong.

 

Bender

[+nincehelser]

It seems to me that EL type light is usually rated by how many hours it takes them to get to half brightness (as in the "bulb" "wearing" out). I think I read that somewhere once. But then again, I could be wrong.

That jibes with what I've heard.

 

What's more worrisome is that some folks are claiming the sun has dimmed 10% over the last 30 years.

 

http://www.guardian.co.uk/life/feature/sto...1108853,00.html

 

It might be a good idea to start stocking up on batteries

 

George

[+Prime Suspect]

What's more worrisome is that some folks are claiming the sun has dimmed 10% over the last 30 years.

 

http://www.guardian.co.uk/life/feature/sto...1108853,00.html

The story doesn't say the sun is dimming. As a matter of fact, it says just the opposite:

"So what causes global dimming? The first thing to say is that it's nothing to do with changes in the amount of radiation arriving from the sun."

 

This story is about the change in the amount of light that reaches the earth through the atmosphere.

[+nincehelser]

The story doesn't say the sun is dimming. As a matter of fact, it says just the opposite:

"So what causes global dimming? The first thing to say is that it's nothing to do with changes in the amount of radiation arriving from the sun."

 

This story is about the change in the amount of light that reaches the earth through the atmosphere.

Quibble, Quibble, Quibble. Since most of us live on the same planet, so it all means the same

 

What remains to be seen is how this plays into the hands of the psueduo-scientists who have been proclaming that the sun is in the process of shutting down.

 

George

[Bender]

I would think that since the sun has no outside source of energy that it has been in the process of shutting down since the minute that it began. Am I correct?

 

Bender

[+nincehelser]

I would think that since the sun has no outside source of energy that it has been in the process of shutting down since the minute that it began. Am I correct?

It depends on how you look at it, I guess. The reason some were thinking the Sun is in the phase of shutting down is that we couldn't detect any of the neutrinos that should be pouring out if the expected nuclear reactions are occuring.

 

Instead of figuring we just hadn't built a good enough detector yet, the fringe assumed the necessary reactions to power the sun were all used up, thus darkness and the last days would soon be upon us.

 

Fortunately, I believe enough neutrions have been detected recently to put that "theory" to bed.

 

George

Edited December 19, 2003 by nincehelser

[+Prime Suspect]

Quibble, Quibble, Quibble. Since most of us live on the same planet, so it all means the same

No, not really. One may be fixable, the other is not. That's the kind of difference that comes under the category of HUGE.

[+Team GPSaxophone]

I would think that since the sun has no outside source of energy that it has been in the process of shutting down since the minute that it began. Am I correct?

 

Bender

That's deep, Bender

[+GeckoGeek]

Yours eyes have two "recievers" that are stimulated by light and send messages to your brain. RODS are stimulated by colored light and CONES are stimulated by white light. When the light source is colored, everything reflects colored light, and leaving your CONES pretty much in their lower stimulated state. So that you still have "night vision" when you look away.

How does this work considering they have a white light model? Yes, I know about using a red light at night. If they made the night vision claim for SOME models I wouldn't be questioning it.

 

But there's still the question about how one stimulates only the rods considering that the cones respond to light although the response is monochromatic. It's like saying you can't photograph a sunset with black and white film because everything is in color. If I was told the cones didn't respond to a given color, then I'd understand, but again, how does one make the night vision claim for models of different colors?

Edited December 19, 2003 by GeckoGeek

[+nincehelser]

But there's still the question about how one stimulates only the rods considering that the cones respond to light although the response is monochromatic. It's like saying you can't photograph a sunset with black and white film because everything is in color. If I was told the cones didn't respond to a given color, then I'd understand, but again, how does one make the night vision claim for models of different colors?

I think their claim is kind of bogus, at least for any other color than red. About the only possible reality is that the light isn't bright enough to make your pupils contract, or bleach out the rhodopsin in your retina.

 

Note that they said if you're going to hand carry the light, the 180 version is better than the 360. Obviously they recognize that the light is going to mess a bit with your night vision at some level.

 

George

[+GeckoGeek]

I think their claim is kind of bogus, at least for any other color than red. About the only possible reality is that the light isn't bright enough to make your pupils contract, or bleach out the rhodopsin in your retina.

That's what I'm thinking - that it's too dim to really do any damage. I know red is the triditional color for protecting night vision, but I thought I heard mondern research had found something else.

 

This seems to have some more info.

[+nincehelser]

That's what I'm thinking - that it's too dim to really do any damage. I know red is the triditional color for protecting night vision, but I thought I heard mondern research had found something else.

 

This seems to have some more info.

That write-up is interesting, but seems strange. I see a lot of recognizable facts, but I'm not sure where he's going with them. Most of the conclusions seem to be at odds with his thesis, unless "fully dimmable white light" means just turning it off completely.

 

I have seen some people contend that blue is better for night vision, but I don't buy it. Those bluish headlights on cars, and some blue LEDs really bug my eyes.

 

I've gone caving with bluish-cast LED lights, and my personal perception is that I can "see", but not really "see". It hard to describe other than to say I find it uncomfortable, but I know others in the group don't really notice, or actually like it.

 

I'll stick with red to preserve my night vision.

 

George

[+embra]

I think your verdict is the right one, George. Rods and cones will both respond to most wavelengths in the visible spectrum; the rods make light/dark differentiations (like black & white tv) while the cones differentiate between colors (like color tv). Rods respond much better than cones in low-light conditions.

 

However, the rods do *not* respond to light in the red part of the spectrum. So their dark-adjustment (which takes about 30 minutes in low-light conditions to fully adapt) is not disrupted by red light, even though the cones can operate under the same light and give useful information. The cones lose their dark-adaptation, but since it's not worth much anyway, who cares?

 

This was known by a psychologist who advised the RAF in WWII that their fighter pilots need not sit in dark rooms waiting to defend against Hitler's bombers in the Battle of Britain, but could read or play cards under red light conditions until they had to scramble. Their rods would remain fully dark-adapted to give them optimal visual acuity. You also see red light conditions in submarine movies for the same reason.

 

So maybe I'm missing something in what these guys claim, but it seems to me, too, that you risk disrupting the your dark adaptation with any visible light that is not red.

 

Edit: I suppose I should have read that link before rather than after I posted the above. His explanation appears to be reasonable, although I tended to get a little lost in in towards the end. What I think I take away from it is that it may make sense to use additional frequencies to see better in the dark, but it still makes sense that if you are trying to work with light levels below the firing thresholds of cones, you want your cones to be maximally dark adjusted, and red light will disrupt that the least.

Edited December 20, 2003 by embra

[+Prime Suspect]

This was known by a psychologist who advised the RAF in WWII that their fighter pilots need not sit in dark rooms waiting to defend against Hitler's bombers in the Battle of Britain, but could read or play cards under red light conditions until they had to scramble.

I wonder if they modified their playing cards. It would be tough differentiating a heart from a diamond under red light.

[+Stunod]

Here is another link that gives info on flashlight filters and when to use what color.

[+Sidewinder_6]

I currently use three Krill lights. Paid for by my rich uncle whose name is Sam . I have blue, green and red. By far the most flexible light is green followed by blue. The red light is actually kind of pink. I was able to overcome this by wrapping a thin layer of red plastic around the lamp but its light output insn't very good for someone in the civilian world. I haven't noticed any decrease in light output from one set of batteries to the next in any light. Only when a battery is getting weak does the light output get weak. I have never killed a set of batteries in any of these lights because I change them out every time I go out. I don't know how long the light maintains an acceptable brightness on one set of batteries but I have used these lights over the course of 10 nights (roughly 1 to 3 hours per night) without the need to change the batteries. If I was going to buy these for myself to use for survival or marking in a non tactictal situation where I wanted to re-use the light, I would by a green light and my second choice would be blue. Chem-lights still have their use in situations where you would not need to recover the light source to use again