The Sigma 17–40mm F1.8 DC Art is a portable, durable and versatile standard AF zoom lens compatible with Canon APS-C mirrorless cameras. The constant maximum aperture of F1.8 makes it ideal for low-light environments and night scenes, as well as for expression using large bokeh. This lens offers a constant aperture throughout the ultra wide to standard zoom range, and image quality comparable to a prime lens. It is a very compact crop-format zoom lens for stills and video content creation.