Introducing the SEL20F18G Full Frame Lens: A large aperture;ultra-wide angle prime lens for stills and movies. An advanced optical design that includes two AA (advanced aspherical) elements for incredible corner-to-corner high-resolution; along with beautiful bokeh. Two XD Linear Motors deliver fast; precise; quiet AF and tracking in a compact-sized and lightweight Sony G lens body. Internal focusing ensures that focus breathing is effectively minimised. Wobbling is incorporated for smooth; fast and continuous AF performance for movie shooting.