DescriptionBy reducing the distance from the rear of the lens to the focal plane and reducing the size of the image circle to match the size of the APS-C imaging sensor used in digital SLRs such as the EOS 20D camera and Digital Rebel camera,Canons EF-S lenses reduce the size, weight and cost of wide-angle lenses for these cameras while at the same time producing high image quality with superb resolution and contrast at all focal lengths.Real time price comparison from PriceGrabber