Wide angle zoom for ef s mount bodies f28 aperture throughout zoom range 3 stop image stabilizer fast quiet auto focus super spectra coating circular aperture for pleasing background blur passes distance information to e ttl ii with an effective focal length range of approximately 27 88mm 35 mm equivalent the ef s 17 55mm f28 is usm is a powerful lens that delivers remarkable image quality the wide angle zoom allows you to capture more of every scene a