Sigma APO 50-150mm F2.8 EX DC HSM

You need a fast, effectively-stabilised lens for portraiture or product photography., You want a zoom lens that can be used with polarisers and graduated filters., You require good flare resistance in backlit situations. Buy this lens if :, You need a...

You have a camera with a 'full frame' (36 x 24mm) image sensor., You need a small, lightweight lens. Don't buy this lens if:, You have a camera with a 'full frame' (36 x 24mm) image sensor., You need a small, lightweight lens.

poor image quality at the edge for 150 mm,, chromatic abberation should be smaller in APO lens,, noticable astigmatism for focal length range from 100 to 150 mm,, clear vignetting especially at 150 mm,, significant front-focus with Canon 20D.

So which lens you should choose? Sigma 70-200 f/2.8 or Sigma 50-150 f/2.8? First one has better optical performance, especially on APS-C/DX matrix. Astigmatism, vignetting and distortion are well controlled which is not in case of 50-150 model. But all...