Just this week I got together with the optician from my optometrist's office. Like many of you I had lost the front sight sharpness. I have ESS glasses with the corrective lens inserts. I am right handed and shoot that way but am left eye dominate so my front sight is seen by my left eye. We experimented with that lens and changed it to make the front sight clearer but minimize mid and long range affects. I can hardly detect a difference in mid to long range vision and no problem seeing other targets or the big picture. My shooting at 25 yd. is much better due to more precise front sight placement.