The Panasonic Lumix S PRO 24-70mm f/2.8 is an L-mount wide-angle to short-telephoto lens characterized by its constant f/2.8 maximum aperture and sophisticated optical design. Aspherical, UHR and ED elements are used to produce well-corrected imagery with high sharpness, accurate color rendering, and notable clarity throughout the zoom and focus ranges. Additionally, the lens sports a weather-sealed design for use in harsh conditions, and a rounded 11-blade diaphragm contributes to a pleasing bokeh quality with smooth transitions between the in-focus and out-of-focus regions of the image. Standard zoom is designed for full-frame L-mount mirrorless cameras, however, can also be used with APS-C models where it provides a 36-105mm equivalent focal length range. Three aspherical elements and one ultra-high refractive index element help to minimize distortions and spherical aberrations throughout the zoom range in order to maintain edge-to-edge sharpness and illumination. A double-focus system employs both a linear motor and a stepping motor to deliver impressively fast, precise, and quiet autofocus performance. A manual focus clutch allows you to simply push or pull the focusing range to quickly switch between AF and MF focusing modes.