Canon EF 500mm f/4L IS II USM Worthy successor to the lauded Canon EF 500mm f/4L IS USM, the new EF 500mm f/4L IS II USM super telephoto lens features completely redesigned Fluorite optics that deliver sharper images with less chromatic aberration and has a lighter weight thanks to magnesium and titanium construction elements. Because image stabilization technology in super telephoto lenses may inadvertently over-compensate and interfere with composing and framing distant or moving subjects, the EF 500mm f/4L IS II USM includes an advanced third Image Stabilization mode (Mode 3) that activates IS only when the shutter button is fully pressed. This allows users to pan fast-moving subjects and then activate IS only when it is precisely required. Additionally, all three IS modes give the equivalent effect of a shutter speed four stops faster, ideally positioning the Canon EF 500mm f/4L IS II USM for professional action photography, from sports to nature. The addition of the Power Focus mode enables smooth focus change when shooting video. Buttons and switches are redesigned for intuitive, deliberate operation, and dust and water sealing keeps the EF 500mm f/4L IS II USM functioning flawlessly in even the most challenging environments. Specifications Focal Length & Maximum Aperture 500mm f/4.0 Lens Construction 16 elements in 12 groups (Including drop-in rear filter, Fluorite: G2 and G4, UD Lens: None) Diagonal Angle of View 5° Focus Adjustment Inner focusing system, with focusing cam Closest Focusing Distance 3.7m / 12.14 ft. Filter Size 52mm Drop-In Max. Diameter x Length, Weight 5.7 x 15.1, approx. 112.5 oz. / 146 x 383mm, approx. 3190g † Prices and specifications subject to change without notice.