The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tokina 11-16mm f2.8 DX and the Canon 17-40mm f4.0L USM for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is an important deciding factor when comparing two lenses. Canon 17-40mm f4.0L USM is the longer of the two lenses at 97mm. The Tokina 11-16mm f2.8 DX with a length of 89mm, is 8mm shorter. On the other hand, there is no difference between the max diameters of these lenses, both coming at 84mm.
The weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Canon 17-40mm f4.0L USM weighs 500g, 10% (60g) lighter than the Tokina 11-16mm f2.8 DX's weight of 560g.
Below you can find the dimension and weight table of the Wideangle Zoom Lenses in Canon EF Mount for size comparison purposes.
Wideangle Zoom Lenses in Canon EF Mount for Size Comparison
Lens Mounts
Both the Tokina 11-16mm f2.8 DX and the Canon 17-40mm f4.0L USM has the same Canon EF lens mount. Some of the latest released cameras that are compatible with the Canon EF lenses are Canon T8i, Canon 90D and Canon SL3.
Tokina 11-16mm f2.8 DX is also available in Nikon F (DX) and Sony Alpha mounts.
Focal Range
Tokina 11-16mm f2.8 DX has a focal range of 11-16mm and 1.5X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 17.6-25.6mm when used on a APS-C / DX format camera. Canon 17-40mm f4.0L USM has a focal range of 17-40mm and 2.4X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 27.2 - 64mm.