you're feeling eye strain cause you played too much and your eye is not used to it yet =) don't worry, you'll get used to it (that's why you should start with a low setting and progressively increase the 3D... say 1/4 every week to be at full 3D in a month?)
OoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoOoO







