Sigma 17-70 mm lens works perfectly with my Canon 50D and 70D cameras. Bought as replacement for the Sigma 18-250 mm lens. Purchased mainly for landscapes and portraits and it does the job incredibly well – this lens is a real workhorse. At the macro end it has a very good bokeh, even better than the Canon 24-105 mm in my experience. The lens has a very quiet motor with effortless operation. The IS is very efficient especially at the shortest aperture. The Sigma 17-70 mm makes handheld photos sharp even at 1/5 seconds, which makes it extremely good in comparison to the Canon 24-105 mm F/4L, which was possible at 1/20 seconds, the lowest setting. It makes the Sigma 17-70 mm very useful in dark indoor environments at short lengths. At 70 mm in the dark you can see chromatic aberrations, at 17-35 mm it’s perfect. Excellent for macro shots, portraits and landscapes. Ultimately, it’s a really high quality lens with a new, clean, matt black barrel design.