"I have to use the lightest tint I can because I can't distinguish color very well with those dark glasses. I've lost orientation several times with a dark pair and replaced them with a lighter pair. "

zetor ,i never thought of that but it happened to me once this year,while circling around,the plane was a light and dark gray,almost like black primer,i couldn't tell what was what but my glasses turn dark in the sun,the brighter the sun the darker they get,i might pick up a pair of just sunglasses and see if it makes any difference.
Thanks