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 Canon 16-35mm f4L IS USM 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. Sigma 18-35mm F1.8 DC HSM is the longer of the two lenses at 121mm. The Canon 16-35mm f4L IS USM with a length of 113mm, is 8mm shorter. On the other hand, the Canon 16-35mm f4L IS USM has a larger diameter of 83mm 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. Canon 16-35mm f4L IS USM weighs 615g, 24% (195g) lighter than the Sigma 18-35mm F1.8 DC HSM's weight of 810g.
Filter Threads
The Sigma 18-35mm F1.8 DC HSM has a filter size of 72mm whereas the Canon 16-35mm f4L IS USM has a 77mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 72mm filters that we recommend you to consider for the Sigma 18-35mm F1.8 DC HSM:
And these are the 77mm filters that we recommend for the Canon 16-35mm f4L IS USM:
Lens Mounts
Both the Sigma 18-35mm F1.8 DC HSM and the Canon 16-35mm f4L IS 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.
Sigma 18-35mm F1.8 DC HSM is also available in Pentax KAF , Sony Alpha, Sigma SA and Nikon F (DX) mounts.
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 Canon 16-35mm f4L IS 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.