The ef 50mm f12l usm is a peerless new standard lens featuring an ultra large aperture for a narrow depth of field and soft background blur so loved by photographers everywhere the ef 50mm f12l usm is suitable for any shooting situation its lens coating and construction are optimized to minimize the ghosting and flare that frequently occurs when lenses are used with digital cameras this high performance weather resistant lens delivers all the superb image resolution and contrast you expe