"katysails" wrote in message

My present prescription sunglasses are gray, but very dark. I really do
not like the purple clip-ones...makes the world look like a strange
place...was wondering about the kind that darken when you go out and
lighten when you go back in and was wondering about response time...

In glass (not recommended) these are called Photogray or Photobrown Extras.
In hard resin, they are known as Transitions. They may get darker than you
prefer. Serenghetti makes a number of excellent lenses for sailors. My
favorite is their vermillion polarizer. Not too dark and a great polarizer.
Check it out. Oh, and by the way, it may be glass, so don't count on them
to be safety-type lenses.

Max