The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tokina 16-50mm f2.8 DX and the Sigma 18-35mm F1.8 DC HSM 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 18-35mm F1.8 DC HSM is the longer of the two lenses at 121mm. The Tokina 16-50mm f2.8 DX with a length of 97mm, is 24mm shorter. On the other hand, the Tokina 16-50mm f2.8 DX has a larger diameter of 84mm compared to the Sigma 18-35mm F1.8 DC HSM's 78mm 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. Tokina 16-50mm f2.8 DX weighs 610g, which means it is 200g (24%) lighter than the Sigma 18-35mm F1.8 DC HSM which has a weight of 810g.
Below you can find the dimension and weight table of the Standard Zoom Lenses in Canon EF Mount for size comparison purposes.
Standard Zoom Lenses in Canon EF Mount for Size Comparison
Lens Mounts
Both the Tokina 16-50mm f2.8 DX and the Sigma 18-35mm F1.8 DC HSM 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 16-50mm f2.8 DX is also available in Nikon F (DX) mount.
Sigma 18-35mm F1.8 DC HSM is also available in Pentax KAF , Sony Alpha, Sigma SA and Nikon F (DX) mounts.
Focal Range
Tokina 16-50mm f2.8 DX has a focal range of 16-50mm and 3.1X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 25.6-80mm when used on a APS-C / DX format camera. Sigma 18-35mm F1.8 DC HSM has a focal range of 18-35mm and 1.9X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 28.8-56mm when used on a APS-C / DX format camera.