The Leica L-mount 90mm f/2.8 DG DN Contemporary Lens from Sigma is a short-telephoto prime with impressive optical performance. It is well-suited for portraiture and selective everyday shooting and offers a fast f/2.8 aperture for controlling depth of field and working in less-than-ideal light. This lens includes an aspherical element and five special low dispersion elements to control a variety of aberrations and achieve notable sharpness and clarity. The lens incorporates a manual aperture ring for enhanced tactility, and also featured is a stepping motor for quick and quiet AF performance. A rounded nine-blade diaphragm lets you achieve pleasingly smooth bokeh, and the lens's all metal body is weather-sealed to suit working in inclement conditions.