Designed for wedding, portrait and sports photographers, the Sony 135mm has an 11 blade diaphragm that delivers stunning bokeh with circular out-of-focus highlights. The lens has 13 elements in total, including a Super ED and ED and an extreme aspherical (XA) that combine to suppress common telephoto aberrations plus maximize overall resolution. The lens also features four XD (extreme dynamic) linear motors, two for each of the focus groups, which results in fast, accurate and responsive AF. The lens has two customisable focus and hold buttons plus a linear response focusing ring that is ideal for video work.