I had a breif chance today to try the Sigma 120-300 f2.8 OS against a Canon 300 f2.8 IS mkI. Nothing scientific in my testing just put one on my 7D and then the other, just testing in my front garden taking shots of wood pigeon who are clearly setting up home. I turned off the IS/OS as I was trying for flight shots and was getting decent shutter speeds. It seemed to me that the AF speed and acuracy of tracking was very simialr for both (though the Canon had the slight edge in tracking). Looking at the images on my PC they have both delivered decent results with a similar percentage of keepers. Like I say nothing scientific but I was pleasantly surprised by how well the Sigma performed, it is clearly a set up from the non-OS version of the lens. I did also do some low light test shooting with the Sigma indoors (didn't compare to the Canon) and at ISO800, f2.8, 1/60th of a second the OS did the job well enough for me to get sharp shots of my dog!
Below are some wood pigeon shots for my shoot out - some from each lens, I'd say it is reasonably hard to tell them apart. Shot in RAW, all processed with the same LR settings only variation is cropping (none are heavily cropped).
Below are some wood pigeon shots for my shoot out - some from each lens, I'd say it is reasonably hard to tell them apart. Shot in RAW, all processed with the same LR settings only variation is cropping (none are heavily cropped).
