The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 18-35mm F1.8 DC HSM and the Tokina Opera 16-28mm F2.8 FF for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is a crucial factor to consider when comparing two lenses. Tokina Opera 16-28mm F2.8 FF is the longer of the two lenses at 134mm. The Sigma 18-35mm F1.8 DC HSM with a length of 121mm, is 13mm shorter. Besides being longer, the Tokina Opera 16-28mm F2.8 FF also has a larger diameter of 89mm compared to the Sigma 18-35mm F1.8 DC HSM's 78mm diameter.
The weight of a lens is equally significant as its external dimensions, particularly if you intend to handhold your camera and lens combination for extended periods. Sigma 18-35mm F1.8 DC HSM weighs 810g, which means it is 130g (13%) lighter than the Tokina Opera 16-28mm F2.8 FF which has a weight of 940g.
Lens Mounts
Both the Sigma 18-35mm F1.8 DC HSM and the Tokina Opera 16-28mm F2.8 FF 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.
Sigma 18-35mm F1.8 DC HSM is also available in Pentax KAF , Sony Alpha, Sigma SA and Nikon F (DX) mounts.
Tokina Opera 16-28mm F2.8 FF is also available in Nikon F (FX) mount.
Focal Range
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.
On the other hand, the Tokina Opera 16-28mm F2.8 FF has a focal range of 16-28mm and 1.8X 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 - 44.8mm.