The M.Zuiko Digital ED 8-25mm f/4 PRO from Olympus is an ultra-wide Micro Four Thirds zoom lens with the equivalent full-frame format zoom range of 16-50mm. Its sophisticated optical design, which includes a variety of aspherical, low dispersion, and high refractive index elements, reduces both chromatic and spherical aberrations throughout the zoom range for notable clarity, sharpness, and color accuracy. Ultra wide-angle to portrait-length zoom lens designed for Micro Four Thirds mirrorless cameras provides an 8-25mm equivalent focal length range. A ZERO (Zuiko Extra-low Reflection Optical) coating has been applied to individual elements to minimize lens flare and ghosting for improved contrast and color fidelity when working in strong lighting conditions. Constant f/4 maximum aperture enables consistent low-light performance and selective focus control throughout the zoom range. Manual focus clutch allows the focusing ring to be quickly pulled into place for direct, intuitive focus control. Dust-, freeze-, and drip-proof design ensure the lens' performance in inclement and harsh conditions. Front optic features protective fluorine coating. Movie & Still Compatible (MSC) autofocus system benefits both photo and video applications due to its smooth, quiet, and fast performance.