Originally Posted by
Lazy Dog
Photochromic lenses are not only effected by UV light, but they are also dependent on the temperature. Clear sunny conditions around 75 degrees are the ideal conditions for a quick fade rate and darkest tint density. Hot 95 degree summer weather will result in slower fade rates and a lighter tint color. Just something to keep in mind...
With the Oakley brand, the have different photocromic lenses. The Black Iridium lense looks like it for dark to moderately sunny. Probably, better for evening riding. The VR50 go from 50% to 10% of light transmission, which seems pretty dark. My other lense is the Fire, which is pretty dark.