canon ef 17 40mm f 4 l usm lens camera lenses onestop digital
a new and affordable l series ultra wide angle zoom lens that s ideal for both film and digital slrs superior optics are assured by the use of three aspherical lens elements in addition to a super ud ultra low dispersion glass element optical coatings are optimized for use with digital cameras this lens focuses as close as 11 inches 0 28m and offers both canon s full time manual focus and a powerful ring type usm for fast and silent af it has a constant f4 maximum aperture and offers the choice of screw in 77mm filters or a holder in the rear of the lens for up to three gel filters finally it offers weather resistant construction similar to other high end l series lenses