"john smith" wrote in message news:jsmith-

| So turn up the lights so you can see the diagram.

Try a green or blue LED light.
It won't destroy your night vision and provides a brighter light.

"B A R R Y" wrote in message

.....any _single color_ red, blue, or
green light source will protect your night vision.

I've come to the conclusion that perfect night vision, per se, is not the
crucial thing to be protected that many think it is. (I'm talking about
normal operations here, not any kind of military or special ops thing) Just
what is it you're looking for that isn't already lit up? Panel light
reflections off the windshield and side windows are much more intrusive,
imo, and more negatively impactful on traffic scan and the ability to see
outside the airplane than a temporary degradation of night vision. I always
kept cockpit lights very, very low, [sometimes off :-)] but if someone
needs to see a chart or something, turn up the lights for moment or a
half-minute, get your info clearly and without squinting, then turn the
lights back low.