The Canon EF 100-400mm f4.5-5.6L IS USM Telephoto Zoom Lens is a superior quality telephoto zoom lens for Canon DSLR cameras.
L-series lenses from Canon are famous for their superior optics and durability. The EF 100-400mm F4.5-5.6 is no different. Though it lacks a constant aperture throughout its zoom range users should find that this lens nevertheless enhances their photography to a substantial extent.
According to Canon:
L-series super telephoto zoom lens equipped with an Image Stabilizer. The fluorite and Super UD-glass elements largely eliminate secondary spectrum. The floating system also ensures high picture quality at all focal lengths. The Image Stabilizer has two modes and it is compatible with Extenders 1.4x II and 2x II.
