Review on Ultra Wide Angle Zoom Lens for SLR Cameras - Canon EF 17-40mm f/4L USM by Bima ᠌

Very high quality item, like all Lki. I don't really see an alternative. Before him was Tamron 17-35, which is lighter, with a higher aperture ratio and a price 2 times less. After switching to Canon 17-40, I won a little in focusing speed and color reproduction became more correct (the tamron liked to go violet). However, aperture 4 significantly increased shutter speed, which is inconvenient of course. Tamron at 17 mm gave aperture 2.8 with excellent sharpness. In general, the 17-40 is a wonderful lens, of high optical and technical quality. Starting from f / 7, the sharpness is ringing, the chromaticity is almost absent as a view! See my albums for examples of photos taken with this and other lenses. I wish you good luck with your choice!