Sigma 120-300mm f2.8 dg os hsm
This is the OS version and a cracking lens it is too, be a little careful with Sigma lenses though and check they focus where they should, some sigmas i have had and used in the past and dare i say the second hand ones have had issues with this type of problem. Saying that they are much better these days. If you buy from new you can ask to check it out before buying it, I advise this strongly if you are going to part with £2000 for anything. I asked for 3 lenses and compared all 3 against each other then put the memory card from all 3 lenses onto there computer to check at 100% to see if there were any issues, for me at least there were none in the focusing department or so little it was not worth the worry. I checked the Canon 300mm f2.8 l is usm, sigma prime 300mm f2.8 none os and the Sigma os 120-300mm f2.8. The none os prime from sigma went straight back in the box after a test with that, I don't recommend this lens to anyone, then the Sigma and Canon, both were so close on IQ it was not worth worrying about, the Sigma was sharp where it needed to be sharp, in the centre, it softens very little in the corners but nothing major, I was using a full frame camera as well so this would have more impact. The Canon was sharp throughout the image and in the corners. My overall view was that as long as the centre was sharp on a full frame camera I can afford to crop the images If I wished too. so all in all an amazing lens but do test them before buying Wink.