The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Canon 16-35mm F2.8L III and the Tokina 12-28mm f4 Pro DX for their suitability to various photography scenarios:
Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Canon 16-35mm F2.8L III is the longer of the two lenses at 128mm. The Tokina 12-28mm f4 Pro DX with a length of 90mm is 38mm shorter. Besides being longer, the Canon 16-35mm F2.8L III also has a larger diameter of 89mm compared to Tokina 12-28mm f4 Pro DX's 84mm diameter.
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. Tokina 12-28mm f4 Pro DX weighs 530g, 32% (260g) lighter than the Canon 16-35mm F2.8L III's weight of 790g.
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 Canon 16-35mm F2.8L III and Tokina 12-28mm f4 Pro DX has the same Canon EF lens mount. Some of the latest released cameras that are compatible with the Canon EF lenses are Canon 1D X III, Canon 6D MII and Canon 5D MIV.
Tokina 12-28mm f4 Pro DX is also available in Nikon F (DX) mount.
Focal Range
Canon 16-35mm F2.8L III has a focal range of 16-35mm and 2.2X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides an 35mm (FF) equivalent of 25.6 - 56mm.
Tokina 12-28mm f4 Pro DX has a focal range of 12-28mm and 2.3X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 19.2-44.8mm when used on a APS-C / DX format camera.