Developed to be the workhorse for events, portraiture, and other mid-length subjects, the Panasonic Lumix S PRO 70-200mm f/2.8 O.I.S. is an L-mount telephoto zoom characterized by a bright f/2.8 constant maximum aperture and sophisticated optical and focusing performance. The optics layout incorporates several aspherical and low dispersion elements in order to minimize chromatic and spherical aberrations throughout the zoom range for higher clarity, sharpness, and accurate rendering. Complementing the optics is a unique double focus system, which utilizes both a linear motor and a stepping motor, to provide especially fast and precise focusing performance. A focus clutch also enables especially quick switching between AF and MF settings for fine-tuned control. Additionally, an Optical Image Stabilizer reduces the effects of camera shake for sharper handheld shooting and the lens sports a weather-sealed design for use in harsh conditions.Telephoto zoom is designed for full-frame L-mount mirrorless cameras, however can also be used with APS-C models where it provides a 105-300mm equivalent focal length range.Bright constant f/2.8 maximum aperture maintains consistent illumination throughout the zoom range and affords greater control over depth of field.One aspherical element helps to minimize distortions and spherical aberrations throughout the zoom range in order to maintain edge-to-edge sharpness and illumination.Two ultra extra-low dispersion elements and three extra-low dispersion elements greatly reduce chromatic aberrations and color fringing in order to produce a high degree of clarity and color accuracy.A double focus system employs both a linear motor and a stepping motor to deliver impressively fast, precise, and quiet autofocus performance. A focus clutch mechanism has also been incorporated, which allows for near-instant AF/MF switching.Focusing system has been designed to suppress focus breathing for greater versatility when used for video applications.Optical Image Stabilizer minimizes the appearance of camera shake b for sharper handheld shooting, and also supports the Dual I.S. and Dual I.S. 2.0 functions for increased stabilization performance up to approximately seven stops.Splash, dust, and freezeproof design benefits working in inclement weather conditions down to -14 F.Rounded 11-blade diaphragm contributes to a pleasing bokeh quality.Removable rotating tripod collar with Arca-type dovetail is included and benefits working with the lens atop a tripod or monopod.Compatible with optional DMW-STC14 and DMW-STC20 teleconverters to further extend the reach of this lens.