Why do they use red lights on a submarine when in combat?
I've read a few webpages on the subject but can't find anything conclusive.
I guess there are two parts to the question: why not use white light, and if you use a colour, why red? I read that the eye is more receptive to green so 'less' green would be needed and objects would be less 'coloured', and that reading in red light will make eyes more tired. The advantage for red light seems to be that eyes can adjust to darkness more quickly but I don't see how that's good - if a sub goes dark surely you're screwed anyway?!