I use glasses when I am working. I have an astigmatism (oval shaped eyes) and I have been perscribed contact lenses to wear for everyday use if I find my eyes get tired. I typically use them for driving at night but that is about it. Now I don't use any lenses when I play tennis because the one perscribed to me seem to totally mess up my depth perception and my glasses just tend to fog up. I can see nice and clearly but it is like looking at a monitor and if you have not played a baseball or tennis first person type video game, it can be really tricky to judge how close the ball in the game is when you are trying to hit it. So now I just assume that my game is going to suck when I play under the lights at night so I don't even get frustrated when I start shanking balls off my frame. I also seem to suffer some eye fatigue, particularly when I have not gotten a full nights rest, and I feel the need to rub my eyes to try and gain focus on the ball. I can tell it is going bad when I see a blurred ball during my service toss. What I would really like to find out is if anyone else has dealt with this issue and has experienced an increase in performance as a result?