Stealth LED Color

Green

Also look at the 'covert' style of lights the restrict the beam to "forward only". Stopping 'side lighting', to keep from seeing the reflector or the LED will greatly improve your "stealthiness". The deeper the shield the better the result.

Mated to a low intensity beam illuminating a small field will yield a very small light-print.

Photon has a good page on different LED colors and their usage.

Why the need for such stealth?

Any colored light will be visible in a dark forest.

If you want true stealth, it's going to be IR.

Restricting the light to downward paths and eliminating side-ways beaming light is the biggest thing. A deeper parabolic reflector and 1/2-3/4" tunnel in front of the lens will block most of the side spill that telegraphs your position. (Take a look at a military L-shaped flashlight for insights). In the photon series, the Doug Ritter / equipped to survive version is one with a sheild to reduce side-spill.

After side-spill, light intensity is the biggest issue. All colors will give away your position about evenly, and in proportion to the amount of sidespill and their intensity.

Also, using a red light that doesn't destroy your night vision will allow you to use the light a little less often. Green appears brighter than red to you when you are doing tasks, and allows you to see the red lines on topo maps (unlike red) – but does degrade your night vision (although no nearly as much or as long as white light).

Personally, I'd use the Fexix 1 AAA or AA set on low with a home-made 3/4" tunnel and red filter (mini-mag light makes some) – and just be careful to keep it pointing straight down when I was using it in "stealth mode".

Simon,

How about nightvision goggles?

Good advice all, thanks.

@Ben and Ken: the best discussion of colors and night vision is this article on Night Vision.

@Kevin: Even though it’s mostly legal to camp along the AT, some of the trail passes thru parkland where camping is “prohibited” (which I interpret as Boy Scout camping, car camping, and hoodlums lighting fires while getting trashed on alcohol or other…) So as not to have to explain the difference between the letter of the law and the generally accepted AT code to some birders passing by after dusk, I prefer to remain out of sight. Lighting is an issue and I agree that when viewed directly all lights are visible; I was thinking reflected light that might escape and “catch” on leaves or tree trunks.

@Greg/John: I read somewhere that a low level of green just barely providing a b/w image to the eye (try it if you can, it’s bizarre) is a much lower level than the equivalent amount for a red light (since the eye is much more sensitive to green). I like the idea of a tube creating a covert nose like the Photon Freedom lights, sounds like a nice DIY project for my Fenix L0D (the non-covert Photon Freedoms look like a bear to retrofit).