I understand that red light can help maintain night vision, but does it also help in preventing your light from being seen?
For example, walking in a campground or home with childern, would the red light make it harder to be easily visible?
IIRC my Psych. 101 class from a billion years ago, the perception of light as a signal or warning has to do with both light level and color. The reason the color is important is not only the ability of the eye and brain to recognize certain colors better and faster, but also because of how we are trained. That is, again IIRC, yellow is actually recognized faster at the same level as a red light, but we are trained to recognize red as a stop/emergency light and yellow as "only" caution.
So, given the same amount of light from the observer's point of reference, red or yellow would get a better "this is something I'd better pay attention to" reaction than green or blue.
At night, your eyes have a color shift away from red and towards cyan (blue-green) If you are using a rather dim red light, and don't show the source at an observer, it is much harder to notice than white or green.
Playing around in the desert with red lights, my Arc AAA red was much less noticable than the Peak AAA 5 red LED light. If there was a high level of ambient light, it was close to impossible to see with the Arc so I used the Peak.
As beezaur said, red light is less noticable (or bothersome) to other people who may see you using the light (as in a camping setting, or while navigating around a room with someone else who is trying to sleep). I use a red filter for my light to keep from spooking deer when hunting; it seems to work.
You should consider IR light if you want it to be invisible to others. [img]/ubbthreads/images/graemlins/cool.gif[/img]
IIRC red light is harder to notice because its not only absorbed by most materials, but your eyes are not overly sensitive to it, on the other hand, green is absorbed by some maritals, and our eyes are very very sensitive to it, so it appears brighter and easier to notice.