Sigma 18-200mm DC 3.5-6.3 Lens is equipped with Sigma’s proprietary technology OS "Optical Stabilizer" function for treatment of camera shake and movement. The function make use of two sensors inside the lens in order to detect vertical and horizontal movement of the camera and works by moving an optical (IS) image stabilizing lens group, to effectively compensate for camera shake. The new Sigma 18-200mm OS Lens automatically detects movement of the camera and compensates for camera shake, when capturing moving subject such as motor sports, flying objects or subjects with un static status. Sigma 18-200mm OS lens is equipped with super multi-layer (SML) lens coating for correction of flare and ghost. Sigma 18-200mm DC OS Lens demonstrates superior image quality throughout the entire zoom range. It has an inner focusing system (IFS) for making the focus soft, queit and fast. The entire focus components of the lens move inside the lens body, makes the front lens element remain static during autofocus. With the virtue of IFS the lens is suitable for using with circular polarizing filters and the petal-type lens hood (supplied). The lens has a high zoom ratio and is exclusively designed for digital Single-Lens-Reflex cameras. Sigma 18-200mm OS lens is capable of focal lengths from wide-angle to telephoto zoom. It is equipped with a couple of Special_Low_Dispersion (SLD) glass elements and two hybrid_aspherical lenses, offer the best correction for all_types_of_aberrations, and enables this extended range super zoom lens to be housed in a compact and lightweight construction. It has 70 mm diameter, 78.1 mm length, and weighing just 405 gm OR 14.3 oz.