Canon 17-40mm F4L USM Zoom - Description:
The 17-40 mm lens is almost legendary and does produce high quality results. But with the ever-increasing resolution of high-end sensors and Canon’s recently stated intention to produce more full frame sensors digital cameras, can the 17-40 mm lens keep up with the challenges. Canon 17-40 mm is widely recognised as a lens with good contrast and control of distortions and the handling of chromatic aberrations is pretty good.

Canon 17-40mm F4L USM Zoom - Specifications:

Focal Length	17-40mm
Max.Aperture	1;4
Construction	12 elements in 9 groups
Diagonal Angle of View	104° -57° 30'
Inner focusing system	USM
Closest Focusing Distance	0.28m / 0.9 ft.
Type	Rotating Type Zoom System
Filter Size	77mm
Max. Diameter x Length	3.3" x 3.8" / 83.5mm x 96.8mm
Weight without packages	1.1 lbs / 500g

Canon 17-40mm F4L USM Zoom - Features:
Optimized for Digital Imaging
High Speed Rear Focusing
Close Focusing to 11 inches
Non Rotating Front Element
Rear Gel Filter Holder
Shorter and about 35% lighter than 16-35 f/2.8 L-Series Lens

Canon 17-40mm F4L USM Zoom - Item Includes:
Canon front & back caps.
Canon Pouch Case (LP1319).
The 17-40 mm instruction manual,
lens Hood (EW-83-E).