Sony Alpha 20mm f/2.8 E-Mount Prime LensNot only will the 20mm (30mm in 35mm full frame format) focal length and f 2. 8 maximum aperture appeal to experienced photographers, but the outstanding resolution of this lens will satisfy their most stringent image quality requirements as well. Three aspheric elements help to achieve superb contrast and resolution right out to the image edges, while simultaneously enabling a compact 20. 4 mm thick pancake design that makes for a portable