 "EF 100mm f/2.8 Macro USM"@en "Canon EF USM | Canon Online Store"@en
"Macro Lens"@en 
 Focal Length & Maximum Aperture 100mm 1:2.8 Lens Construction 12 elements in 8 groups Diagonal Angle of View 24° Focus Adjustment Inner focusing system with USM Closest Focusing Distance 0.31m / 1 ft. (film plane to subject) Filter Size 58mm Max. Diameter x Length, Weight 3.1" x 4.7", 21.1 oz. / 79.0 x 119.0mm, 600g
 "Canon EF 17-40mm f/4 L USM Lens"@en "Camera Lenses :: Canon Lens - Onestop Digital"@en
"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.  "@en 