11-30-2010, 02:02 PM
I would stay away from the Sigma 150-500mm, It is terrible from 400-500 and the AF is slow and unprecise. My girlfriend had it for 9 month and she sold it on. Our findings matching the review over at lenstip. http://lenstip.com/184.1-Lens_review-Sigma_150-500_mm_f_5.0-6.3_APO_DG_OS_HSM-Introduction.html