Sony Alpha E-mount 20mm F2.8 Lens is characterized by three aspherical lens elements which correct distortions and aberrations. In particular, image quality in peripheral areas has been dramatically improved compared to previous lenses. The high resolution and excellent contrast assures richly detailed images free of distortion, making the lens an outstanding choice for a wide range of subjects such as casual snapshots to majestic landscapes. Compact length Measuring a mere 13/16 inches (20.4mm) the lens is 2mm shorter than the SEL16F28 High Quality Exterior The aluminum alloy lens barrel is inlaid into a molded-plastic component for a lightweight yet durable construction and features beautiful laser engraving of the product name and focal length for a stylish finish. The control ring allows for easy operation while the lens exudes a stylish appeal. Circular Aperture The SEL20F28 features seven aperture blades that form a near circle.