Canon EF 17-40mm f/4.0 L USM Lens Review
The Canon EF 17-40mm f/4.0 L USM is a decent choice if photographers often themselves zooming out to put all objects in the frame. At about 1.1lbs, the lens is neither overwhelmingly heavy nor feather-light. The excellent build quality is comparable to L-series models, while the lens feels really solid.
The lens is properly sealed against dust and liquid, but it’s strongly recommended for users to get a 77mm filter. The built-in USM feature allows for quick, quiet and smooth autofocus. Overall, the Canon EF 17-40mm f/4.0 L USM produces stunning images with deep contrast and saturated colors.