My sextant has a green LED that works very nicely. It illuminates an area only about the size of a thumbprint...perfectly adequately!
Now that LEDs are getting cheaper, I am thinking of installing downward pointing red LEDs to illuminate steps, handhold, ways to the head, etc. It seems a way to show where the important stuff is specifically, while preserving night vision (I can sit in the head, and in the pitch dark, the tap and the towels aren't going to be an issue).
The point is that on a moonless, cloudy night, the "cut-off" between dark-adapted vision and virtually blind can be sudden, and really dim red LEDs could save a twisted ankle or a concussion from missing a handhold.
My aft cabin is like a cave, with only two aft 7 x 14" portlights, and so I had to think creatively.