The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 70-300mm F4-5.6 DG and the Canon 75-300mm f4.0-5.6 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 75-300mm f4.0-5.6 IS USM is the longer of the two lenses at 138mm. The Sigma 70-300mm F4-5.6 DG with a length of 122mm, is 16mm shorter. Besides being longer, the Canon 75-300mm f4.0-5.6 IS USM also has a larger diameter of 79mm compared to the Sigma 70-300mm F4-5.6 DG's 77mm 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 70-300mm F4-5.6 DG weighs 550g, which means it is 100g (15%) lighter than the Canon 75-300mm f4.0-5.6 IS USM which has a weight of 650g.
Below you can find the dimension and weight table of the Telephoto Zoom Lenses in Canon EF Mount for size comparison purposes.
Telephoto Lenses in Canon EF Mount for Size Comparison
Filter Threads
Both the Sigma 70-300mm F4-5.6 DG and the Canon 75-300mm f4.0-5.6 IS USM have the same Filter thread size of 58mm.
Below are links to the 58mm filters that we recommend you to consider for these lenses:
Lens Mounts
Both the Sigma 70-300mm F4-5.6 DG and the Canon 75-300mm f4.0-5.6 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 1D X III, Canon 6D MII and Canon 5D MIV.
Sigma 70-300mm F4-5.6 DG is also available in Nikon F (FX) , Pentax KAF, Sony Alpha, Sigma SA, Canon EF, Nikon F (FX), Pentax KAF, Sony Alpha and Sigma SA mounts.
Focal Range
Sigma 70-300mm F4-5.6 DG has a focal range of 70-300mm and
4.3X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of
112 - 480mm.
On the other hand, the Canon 75-300mm f4.0-5.6 IS USM has a focal range of 75-300mm and 4.0X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 120 - 480mm.