Thanks for the link - when did you buy the Sigma? Often these issues seem to be silently fixed by manufacturers, including Canon (like the not very durable on the first 17-55 lenses).
Bought mine a little over a year ago...The lens is always surprisingly sharp...The only BAD thing about the lens is the UGLY mirrored gold band ...Just makes the lens look soooo cheap. so......I got some cool pin-striping tape and covered mine up. I couldn't stand to look at it! LOL!
« Last Edit: July 07, 2012, 05:23:23 PM by infared »
5D III +BG, 5D IV +BG, Canon 15mm f/2.8 Fisheye, Rokinon 15mm f/2.4, Canon 17mm f/4L TS-E, Canon 16-35mm f/4L IS, Sigma 20mm f/1.4 Art, Canon 35mm f/1.4L II, Canon 24-70mm f/2.8 II, Sigma 50mm f/1.4 Art, Canon 85mm f/1.2L, Canon 100mm f/2.8L Macro, Canon 70-200mm f/2.8L IS II & 1.4x III