his Sigma lens measures 86x182mm and weighs 1,160g, making it noticeably shorter butyet whisper-quiet ring-type ultrasonic variety, and the 4-stop image stabilizer has a switchable panning mode, for panning in any orientation. Image quality is very sharp in the 100-300mm section of its zoom range, and doesn’t drop off much at 400mm. The wealth of switchable modes and customisable options boosts real-world handling and performance, making the lens a great buy at the price.