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 OS and the Canon 55-250mm f4-5.6 IS II 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 70-300mm F4-5.6 DG OS is the longer of the two lenses at 126mm. The Canon 55-250mm f4-5.6 IS II with a length of 108mm, is 18mm shorter. Besides being longer, the Sigma 70-300mm F4-5.6 DG OS also has a larger diameter of 77mm compared to the Canon 55-250mm f4-5.6 IS II's 70mm 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 55-250mm f4-5.6 IS II weighs 390g, 36% (220g) lighter than the Sigma 70-300mm F4-5.6 DG OS's weight of 610g.
Filter Threads
Both the Sigma 70-300mm F4-5.6 DG OS and the Canon 55-250mm f4-5.6 IS II 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
The Sigma 70-300mm F4-5.6 DG OS has the Canon EF lens mount whereas the Canon 55-250mm f4-5.6 IS II has the Canon EF-S lens mount. Some of the latest released cameras that are compatible with these mounts are Canon 1D X III, Canon 6D MII and Canon 5D MIV for the Canon EF Mount and Canon T8i, Canon 90D and Canon SL3 for the Canon EF-S Mount.
Sigma 70-300mm F4-5.6 DG OS is also available in Nikon F (FX) , Pentax KAF3, Sony Alpha and Sigma SA mounts.
Focal Range
Sigma 70-300mm F4-5.6 DG OS 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 55-250mm f4-5.6 IS II has a focal range of 55-250mm and 4.5X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 88-400mm when used on a APS-C / DX format camera.