You're a brave one, Randy! I've read somewhere that above 10,000 feet, the sensitivity of your eyes starts to decrease from lack of oxygen. I wonder if that might be more true for those who live closer to sea level.
I know the sensitivity of my eyes decreases from lack of heat!
-------------------- "S.O.E." (Sauron's Other Eye) 16" Royce conical mirror: A permanent work in progress.
10" Homebuilt dob, old Coulter mirror