The Sigma 30mm f/1.4 DC HSM Lens for Canon is a fast lens designed for use in low light. It has optimized light distribution to minimize field curvature and prevent any loss of image quality at the edges of the frame, making this a good night photography option. The Hyper Sonic Motor provides smooth autofocus but full-time manual focus is also supported. It delivers sharp detail and pleasing background bokeh. The lens is ideal for portraits, night sky photography, and street photography.