The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 17-70mm F2.8-4 DC OS HSM C and the Canon 28-135mm f3.5-5.6 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. Canon 28-135mm f3.5-5.6 IS USM is the longer of the two lenses at 97mm. The Sigma 17-70mm F2.8-4 DC OS HSM C with a length of 82mm, is 15mm shorter. On the other hand, the Sigma 17-70mm F2.8-4 DC OS HSM C has a larger diameter of 79mm compared to the Canon 28-135mm f3.5-5.6 IS USM'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 17-70mm F2.8-4 DC OS HSM C weighs 465g, which means it is 75g (13%) lighter than the Canon 28-135mm f3.5-5.6 IS USM which has a weight of 540g.
Below you can find the dimension and weight table of the Standard Zoom Lenses in Canon EF Mount for size comparison purposes.
Standard Lenses in Canon EF Mount for Size Comparison
Filter Threads
Both the Sigma 17-70mm F2.8-4 DC OS HSM C and the Canon 28-135mm f3.5-5.6 IS USM have the same Filter thread size of 72mm.
Below are links to the 72mm filters that we recommend you to consider for these lenses:
Lens Mounts
Both the Sigma 17-70mm F2.8-4 DC OS HSM C and the Canon 28-135mm f3.5-5.6 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 17-70mm F2.8-4 DC OS HSM C is also available in the Pentax KAF3 , Sony Alpha, Sigma SA and Nikon F (DX) mounts.
Focal Range
Sigma 17-70mm F2.8-4 DC OS HSM C has a focal range of 17-70mm and
4.1X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
27.2-112mm when used on a APS-C / DX format camera.
On the other hand, the Canon 28-135mm f3.5-5.6 IS USM has a focal range of 28-135mm and 4.8X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 44.8 - 216mm.
