Canon EF 70-200mm f/2.8L IS III USM is an L-series telephoto zoom. Ideal for a variety of subjects ranging from portraiture to sports, and the f/2.8 maximum aperture excels in difficult lighting conditions and also offers increased control over depth of field for isolating subjects. The optical layout makes use of one fluorite element and five UD elements to suppress chromatic aberrations and color fringing in order to realize a high degree of clarity throughout the zoom range. Also features an Air Sphere Coating, and works to reduce flare and ghosting for greater color fidelity and contrast in all conditions. The Optical Image Stabilizer complements the speed and optics, which compensates for 3.5 stops of camera shake to better enable working handheld and in low-light situations. A ring-type USM and internal focusing mechanism also afford quick, quiet, and accurate autofocus performance and full-time manual focus override.