Canon EF 16-35mm f/4 L IS USM Lens Review
This new ultra-wide angle zoom lens should replace Canon's venerable 17-40mm f/4L optic in their line up of professional lenses. It sports a zoom range of just over 2x and a constant maximum aperture of f/4.
Outstanding sharpness across the frame from maximum aperture; Excellent build quality; Relatively lightweight; Reasonably low distortion; Low CA; Image stabilisation; Fast autofocus; Dust and moisture resistance
Distortion is wavy at 16mm; Far corners remain darker than the image centre; even when stopped down to f/16