The constant f/2.8 aperture across the 17-55mm range, combined with a 3-stop Image Stabilizer, delivers reliable low-light performance and sharpness for APS-C DSLRs. Its optical design incorporates two UD and three aspherical elements to suppress aberrations, while the ring-type USM motor provides fast, quiet autofocus. This lens is best for event and portrait photographers using Canon EF-S bodies who need a versatile, stabilized zoom with a bright aperture.
