Brightest night vision light? (red LED light)?

Right now my best night-adaptation light for camping in dark sky places is a 12-volt LED auto taillight -- I haul a spare deep-discharge battery with me for winter camping for the long nights, the ham radio, the cell phone and the 12-volt electric blanket (hey, I'm married, and I like her company, it's well worth the effort involved).

The red LED taillight was a surprise find at an auto parts place; it's a great tent light (it's a ring of red LEDs around another red LED). A bit cumbersome. Before I try building a portable 12-volt flashlight to handle one of these bulbs, what else is (or will be) available?

I guess I missed the Arc red-orange model and haven't found an Arc AAA-red to buy yet; my little Arc AAA oranges are decent narrow beam lights but don't throw enough sidelight -- and I'm not certain the orange keeps my night adaptation as well as a real red light would do.

What's out there, or going to be available, or home-buildable? I can solder, but thanks to carpal tunnel (failed surgery) my hands aren't real steady so it takes a lot of setting-up to do fine work these days.

I've emailed some of the folks who are building lights -- not sure what's already available for sale aside from special orders.

I could build you something custom, if you wanted. Sorry to hear about the CTS... I'm afraid it will get me too, someday, given how much I type...

If you're looking for NV preserving, you probably want to go with true red, since it doesn't trigger the biological destruction of your adapted eyes. The other question is: how bright do you want? If you want something that's good for just carrying around, and don't NEED waterPROOF, I have had REALLY good experiences with the Skylite from rigel systems (a light astronomers use, but very handy, all around)
http://www.company7.com/rigel/products/skylite1.html
Having both options is nice, and the switch keeps from blasting your eyes if you're just getting up to look around. No fiddling with funky buttons that you have to press 437 times to get the mode of light you want, either.

If you want something different though, I'd be happy to talk with you via PM about what exactly you want...

Paul

How much light are you looking for? I use a red HD in a Rayovac headlamp (Walmart) with 2AAs, and it's pretty bright - at least a lot brighter than a red Infinity.

If you can see the red tint of the beam, you're dark adaption is already shot.

.

Real interesting article... I just whip out the brightest light I have with me 'cause my night vision is shot anyway. /ubbthreads/images/graemlins/icon15.gif /ubbthreads/images/graemlins/jpshakehead.gif

Rich

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If you can see the red tint of the beam, you're dark adaption is already shot.

[/ QUOTE ]

Absolutely not. (you die-hards knew I would have to chime in on this thread, didn't you!)

I read the article mentioned above, titled "Night Vision - The Red Myth" they state: "The key then is finding a hue that we can have at a high enough intensity that we can see the detail we need without activating our rods to the point were they obscure that detail. Most source say this should be nothing shorter than 650nm. Experimentation shows a L.E.D. with a peek around 700nm seems to work best (perceived as a deep red)."

So, red is bad, but it's the one they recommend? I'm confused by this "logical" conclusion, and I'll bet everyone else is, too.

Please read this:

http://flashlightreviews.home.att.net/qa.htm#nightvision

Red is by far the best color for preserving natural night vision. Use the deepest red you can find at the lowest levels needed.

If you're not reading starcharts and looking for insanely dim lights (like distant stars) just use the dimmest white light possible for the situation and you'll maintain a lot of your night adaptation, although not as much as with a red light.

Quickbeam: I have differing information and experience. I want to avoid the "d*s*gr*" word and any sort of argument, so I hope this is taken in a spirit of co-operation on the search for knowledge. /ubbthreads/images/graemlins/smile.gif

I don't have a completely-variable output light of adjustable wavelength to try out.

I do have a CMG Infinity Blue-Green and an Infinity White. I don't have one in red, but I have a Streamlight Stylus in red, and it is way brighter than any of the Infinities. I don't know what wavelength it is, but it's red, not orange-red, so I'd guess 650-690nm.

I'm going to see if I can track down a red Infinity to try.

[EDIT] Poster above removed the link to the article I have referred to in my post, so if the following doesn't make sense, that's why.

Ah. That article again. I've written many responses on this forum to that article. It completely discounts the fact that numerous studies show that the rods (rhodopsin, to be specific) are essentially blind to red light.

At any intensity level, light that is visible to the rods will compromise your extreme low light adaptation to some degree, even if you can't see the "tint" of the light. This is because the rods are being used to detect the low level light you are using and therefore the rhodopsin in the rods is being bleached, albeit possibly at a rate slow enough to allow for rapid regeneration.

Using red light at a low level is picked up by the red cones, not the rods, so turning off the red light allows you to go back to your extreme low light adaptation as if nothing happened. So even at extrememly low light intensity levels, red is better. You may need more of it to see with, but since the rods are blind to it, it has no effect on night adapted vision.

There is nothing wrong with having a disagreement, as long as it's civil! /ubbthreads/images/graemlins/smile.gif

IMHO, these articles, and many like them, are trying to somehow disprove the well known and accepted fact that red light preserves natural night vision better than any other light in a misguided attempt to somehow "modernize" our natural night vision. Unfortunately for these folks, human vision hasn't evolved into something different over the past 10, 100 or even 100,000 years. Red still works best.

Now, mind you, almost all of these arguments, including mine, are academic if you aren't trying to see dim stars on a perfectly clear night in the middle of the country away from any light pollution. We're talking extreme low light adaptation. For any other purposes, the dimmest possible light of any color for the task at hand will allow for decent preservation of intermediate dark adaptation. The more intense the light, the more disruption of your adpatation. Even intense red light causes disruption of night adapted vision, albeit via a different mechanism - it will leave afterimages on the red cones which overlap the visual field of the rods and cause perception of the dim objects to be nearly impossible.

Quickbeam:

I took the links down because I decided not bring up the red-vs-green issue, or argue at all. I apologize to everyone else, here they are for edification and another view, not to start an argument:

http://www.corvus.com/kniffen.htm
http://members.cox.net/rigelsys/why_red.html

The point I was trying to make (and I think we agree on) is that looking for the "brightest possible" red light isn't the best way to preserve dark adaption. The least amount of light is the better choice.

I would like to get myself a light meter and do some measurements. For your astronomical-observing use, how dim of a red light are we talking about? My Streamlight Stylus is way too bright for preserving scotopic or mesopic vision. Is a CMG Infinity dim enough?

That's about the dimmest you'll get for a red LED light unless you go with one of the Skylight astronomy lights. I have a pilot friend who loves the red infinity for cockpit use.

Do you use the CMG or the Rigel Skylight?

I haven't tried a red Infinity yet (I own one but it's not where I can get at it) but I've been using a white one and it's much more comfortable than a brighter light, but for a real night-vision situation (e.g. stargazing) I'd want an adjustable light. The Rigel Systems ones look very nice and are on my want-list.

I do have and use a red Photon II and I think it's better than the white Infinity for night vision, but it's hard to tell since getting anywhere completely dark is very difficult. I'm sure it's less obtrusive if the idea is to walk around somewhere (bedroom where others are sleeping, movie theater etc.) and you need to use a light without bothering other people.

The red light is great for moving around the house at night and not being seen from outside. If something is going on ie a break-in, you can move efficiently through your house without being seen and check things out from different windows. I use a CMG red sometimes tho it is actually a bit on the bright side. I built a single red led 2AA conversion light from a Rayovac which is just perfect for this purpose.

The thing I really like about the rigel light is the truly infinately adjustable brightness. No clickies, no funny blinking modes, just plain usefulness. Operation is simple and intuative. I use it for astronomy and what's really nice about it is that after you've used it a few times, you know just exactly how far to turn the dial to get the amount of light you want - not so much your eyes react, but enough to read or walk around with. I really cannot recommend it more highly. It's a great light, if it fits your needs. It's not an EDC and it's not waterproof (although I'm sure it wouldn't be damaged by a little spill - heck, you could probably drop it in a bucket and after it dried out it would work), but it's a really nice light.

Blikbok: For the astronomical observing, I usually use it at the lowest level I can perform the task I need it for. For reading charts and maps, a very low brightness level(just a little more than just being able to see the dice if I look directly into the leds). For walking around, I select more light, because less light is actually coming back to my eyes, which means that it comes out to about the same brightness level. I think overall, though, the best way to keep your dark adaption is to use the minimal amount of light needed for the task at hand. That's why I love the way the rigel lights just have a wheel to turn for the brightness. It's the most outright useful system I have ever used in a flashlight for brightness control.

BTW, the development of visual purple does take a while, but after it's there, for me anyway, it seems like there is a physical sensation when it's lost. Anyone else experience this? Does anyone else pay enough attention to it when they're sitting in the dark to notice the sensation of everything suddenly getting brighter? It's a very noticeable thing, for me.

/rant Why aren't there more analog "wheel style" brightness/volume controls anymore? Everything seems to have gone to the press this one to go up, that one to go down system... The problem with this is speed... it takes FOREVER to switch settings like that, while with an analog style control, change is nearly instantaneous. Why? Argh, it bugs me... /ubbthreads/images/graemlins/mad.gif /rant

I'm very happy with my new PALight "Selector" with red LED -- it has a single pushbutton; always on in "find-me" dim, and the pushbutton when pressed steps the light up through six very useable levels; when held down it goes immediately to the "find-me" dim level. So it's hard to jolt myself with too much light.

But the Rigelsys (thumbwheel brightness) red astronomer's light -- true analog -- seems even nicer.