Features Sigma’s own unique technology OS (Optical Stabilizer) function The 18-200mm f3.5-6.3 OS is equipped with Sigma’s own unique OS (Optical Stabilizer) technology. This system uses two sensors inside the lens to detect vertical and horizontal movement of the camera by moving an optical image stabilizing lens group, to effectively compensate for camera shake. It also automatically detects panning movement of the camera and compensate for camera shake when shooting moving subjects such as motor sports. Excellent Optical Performance A Special Low Dispersion (SLD) lens and three aspherical glass elements provide excellent correction for all types of aberrations and produce a high level of optical performance throughout the entire zoom range. The super multi-layer lens coating reduces flare and ghosting while producing the best color balance. Enables close-up photography This lens has a minimum focusing distance of 45cm through entire zoom range with a maximum magnification of 1:3.9 making it very convenient for taking close-up pictures. Inner focusing system Because the front of the lens does not rotate, circular polarizing filters and a petal-type hood can easily be used. Magnification scale A magnification scale is displayed on the lens barrel, ensuring ease of use. Zoom lock switch mechanism A zoom lock switch mechanism is provided to prevent the lens from creeping due to its own weight.