I have found articles suggesting that photochromic lenses are not useful in the cockpit. But the reality is that people/pilots that use quality photochromic lenses prefer them. Good Photochromic sunglasses will adjust in the cockpit whether the windscreens are polarized or not. The degree will vary and it basically works together with the windscreens to provide you the optical light for the given situation (of course I'm referring to non polarized for flying). I have tested dozens of Serengetis and have used pilots as my focus group for years. You can checkout my video on Polarization in the cockpit on Youtube "Polarization vs Non polarization in the cockpit". I also find the Serengeti Velocity is the most popular model for pilots. It's a Gradient, Photochromic lens. Please note, I do have a Sunglass business and Specialize in Serengeti Sunglasses for pilots. Years of use and polling has solidified my support of them. Let me know if you have any other questions. Arby
https://youtu.be/0t5GHR6opfI