The lens offers a maximum T stop of 3.1 and has an 11-blade iris that provides round out of focus highlights for a natural looking bokeh. The lens barrel features 300° of stepless, smooth rotation from close focus to infinity, giving you a high degree of precision and consistent focus.
The lens is designed to minimize focus breathing and also has innovative glass construction that counteracts barrel expansion and contraction to avoid temperature-induced marking discrepancies. It has focus distance markings on both sides of the barrel, with the rear markings on an angled surface, making it readable from either side of the camera. It also has a dust and water resistant housing to minimize maintenance.