Key Features Standard lens featuring superb quality and portability. Two high-refraction lens elements and new Gaussian optics eliminate astigmatism and suppress astigmatic difference. Crisp images with little flare are obtained even at the maximum aperture. Superb lens featuring superb quality and portability. f/1.4 speed makes it perfect for available-light shooting. Ideal lens to accompany a zoom when shooting in low-light conditions. Compact and affordable. Only lens in the EF System to combine the extra-small Micro USM and still provide full-time manual focusing when the lens.