The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 12-24mm F4.5-5.6 II DG HSM and the Canon 16-35mm f2.8L II 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. Sigma 12-24mm F4.5-5.6 II DG HSM is the longer of the two lenses at 120mm. The Canon 16-35mm f2.8L II USM with a length of 112mm, is 8mm shorter. On the other hand, the Canon 16-35mm f2.8L II USM has a larger diameter of 89mm compared to the Sigma 12-24mm F4.5-5.6 II DG HSM's 87mm diameter.
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 16-35mm f2.8L II USM weighs 635g, 5% (35g) lighter than the Sigma 12-24mm F4.5-5.6 II DG HSM's weight of 670g.
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 Sigma 12-24mm F4.5-5.6 II DG HSM and the Canon 16-35mm f2.8L II USM 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.
Sigma 12-24mm F4.5-5.6 II DG HSM is also available in Sigma SA and Nikon F (FX) mounts.
Focal Range
Sigma 12-24mm F4.5-5.6 II DG HSM has a focal range of 12-24mm and 2.0X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 19.2 - 38.4mm.
Canon 16-35mm f2.8L II USM 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 a 35mm (FF) equivalent of 25.6 - 56mm.