Sigma 18-35mm F1.8 DC HSM Art Lens for Canon

Part of Sigma’s Art line of lenses,Maximum Magnifications 1:4.3 The convenience of a zoom lens with a fast aperture of a fixed focal length Perfect for landscapes, portraits, still life and close-up photography Internal focusing and zooming allows for easier handling.Sigma has developed special software (SIGMA Optimization Pro) that can update the lens firmware and adjust parameters such as focus. Designed specifically for APS-C sized sensors.Corresponding Mounts:Canon-HSM,DC To use USB Dock, please attach a USB Dock to your lens' mount part, just like you attach your camera to the lens. Please use the supplied USB Cable and connect to a computer which has the dedicated software “SIGMA Optimization Pro” installed. For further information on how to operate the product, please refer instruction manual of “SIGMA Optimization Pro”