The Sigma 18-200mm f/3.5-6.3 DC Lens is specially optimized for digital SLR cameras, and offers an "all-in-one" super-zoom lens solution. This version now incorporates a built-in motor, which gives it the capability to auto focus with all Nikon DSLR cameras (including the D40 and D40x). This lens provides the equivalent focal range of approx. 27-300mm when used with a Nikon digital SLR camera (*).
Its design incorporates aspherical lenses and SLD (Special Low Dispersion) glass that provides the utmost correction for all types of aberrations and enables this extended super-zoom lens to be housed in a compact and lightweight construction.
DC lenses are exclusively designed for digital SLR cameras. The image circle (rear of lens) is made to match the smaller dimensions used for the image sensor on digital cameras. As a result these lenses are also more compact and lightweight, and are better matched to digital SLR cameras.
(*)Note: Not compatible with 35mm cameras or digital cameras using full-size image sensors (e.g. D3, Kodak DCS14n or DCS PRO SLR/n).