I just bought a Canon 24-70 2.8L lens from someone on Craigslist and I think it is a bad copy....anyone have experience sending a lens to Canon for calibration? It seems to have AF issues, images seem to soft, and a lot of my shots are blurry!!! When I tried it out when I met the person it seemed to shoot fine outdoors but now I am getting frustrated. I am wondering what kind of money am I looking at to send it in and get repaired and what kind of turn-around time am I looking at? Thanks. PS. Never buying of CL again!!!