Originally posted 2006-10-31 on Optyczne.pl Recently we published a review of Sigma 70-200 mm f/2.8 EX APO DG HSM Macro - the lens that has good reputation among many users. This is big, solid instrument designed for full frame cameras so we were not surprised that it performed well on APS-C DSLRs.
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