A compact and lightweight 300mm super-telephoto lens with Image Stabilizer(IS), similar to EF 75-300mm f/4-5.6 IS USM. The Image Stabilizer shifts a lens group(11th to 13th elements) in parallel to the film plane. Camera shake is a major cause of blurred images especially with telephoto lenses. The IS system helps resolving this problem. The image stabilizing effect is equivalent to about two steps of shutter speed. “IS Mode 2″ is newly applied to stabilize finder images at panning shots of moving subjects. The optical system uses two UD (Ultra-low Dispersion) glass lens elements(2nd & 5th) to compensate secondary spectrum and provide sharp, high-contrast images from maximum aperture.