Specially designed for wildlife and sport photographers, this state-of-the-art lens is a new standard for telephoto zooms. Build quality is exemplary, with dust- and splash-proof construction for use in the great outdoors, and the zoom can be locked at all marked focal lengths. Images are very sharp, aided by an improved Optical Stabilizer (OS) that helps to avoid blurring from camera shake. Autofocus is fast and quiet, and compatibility with the SIGMA USB DOCK gives scope for user customisation of settings, along with the possibility of firmware updates. For sports and wildlife photographers it’s in a class of its own.