Design and Performance The Sigma 17-40mm f/1.8 DC Art Lens (Canon RF) is designed to be used with mirrorless cameras featuring the APS-C Canon RF lens mount. It features a total of 17 elements in 11 groups, along with four aspherical and four Special Low Dispersion elements to minimise flare and ghosting and suppress various aberrations. Further, with the 11-blade rounded diaphragm, you will get a large, smooth bokeh when used wide open. You appreciate the fast maximum f/1.8 aperture across the zoom range and the close minimum focus distance of just 28cm across the entire zoom range. Video Production The Sigma 17-40mm f/1.8 DC Art Lens is designed for video creation with its bright f/1.8 maximum aperture across the entire zoom range from wide to normal. This makes it ideal for a single-shooter in run-and-gun setups. With an internal zoom mechanism, it can easily be balanced on a gimbal. Sigma’s high-speed, high-response linear actuator autofocus remains both quiet and accurate. Additional Features Two AFL buttons Focus mode switch Water- and oil-repellent coating on front element Dust- and splash-resistant design Durable brass bayonet mount
