imagemeister Loc: mid east Florida

Anybody out there have direct shooting experience with the Sigma 120-300 F2.8 AT 300mm and f2.8 - and with extenders wide open also ?? Please no opinions - speak from experience -- I have read ALL the reviews !

MT Shooter Loc: Montana

I tried one out, but the AF was all messed up when I got it. Returned it and got a second copy which performed flawlessly. A note included with the second lens said this lens has had a lot of AF problems in about half and that the factory was working on a fix. It is electronic and you can still manually focus even with the glitch, but manual focusing seems to defeat the purpose of the fast F2.8 optics which would be great for fast action sports. I will wait for the next generation to make a decision.
By the way, my rental fee was returned in full for compensation of the problem with the first lens.

imagemeister Loc: mid east Florida

How would you rate the sharpness on the one that worked flawlessly ?? Thanks........Larry

MT Shooter Loc: Montana

I have a Nikon 80-200 F2.8 ED IF that I use for basketball games. From F5.6 down they were almost identical. At F2.8 and F4 the Nikon outperforms the Sigma, but not by a whole lot. For sports it would be great, but I wouldn't use it for low light wildlife shots. The center of the frame was good but the sharpness falls off pretty fast going out to the corners. The Nikon is tack sharp from corner to corner at F2.8, thats why I love it.
I also have an older Tokina AT-X Pro 100-300mm F4 zoom that gives me wonderful shots at 300mm and F4. The Sigma was just as sharp at 300mm as the Tokina, but I cannot say it was better, but it did autofocus in half the time as the Tokina. But the Tokina is over 20 years old so that I expected, and not that much of an issue with wildlife unless you are talking birds in flight.