The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 10-20mm F4-5.6 EX DC HSM and the Tamron 10-24mm f3.5-4.5 II LD 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. Tamron 10-24mm f3.5-4.5 II LD is the longer of the two lenses at 84mm. The Sigma 10-20mm F4-5.6 EX DC HSM with a length of 81mm, is 3mm shorter. On the other hand, the Sigma 10-20mm F4-5.6 EX DC HSM has a larger diameter of 84mm compared to the Tamron 10-24mm f3.5-4.5 II LD's 83mm 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. Tamron 10-24mm f3.5-4.5 II LD weighs 406g, 13% (64g) lighter than the Sigma 10-20mm F4-5.6 EX DC HSM's weight of 470g.
Below you can find the dimension and weight table of the Wideangle Zoom Lenses in Canon EF Mount for size comparison purposes.
Ultra-Wideangle Lenses in Canon EF Mount for Size Comparison
Filter Threads
Both the Sigma 10-20mm F4-5.6 EX DC HSM and the Tamron 10-24mm f3.5-4.5 II LD have the same Filter thread size of 77mm.
Below are links to the 77mm filters that we recommend you to consider for these lenses:
Lens Mounts
Both the Sigma 10-20mm F4-5.6 EX DC HSM and the Tamron 10-24mm f3.5-4.5 II LD 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 10-20mm F4-5.6 EX DC HSM is also available in Four Thirds , Pentax KAF, Sony Alpha, Sigma SA and Nikon F (DX) mounts.
Tamron 10-24mm f3.5-4.5 II LD is also available in Nikon F (DX) , Sony Alpha, Pentax KAF and Canon EF mounts.
Focal Range
Sigma 10-20mm F4-5.6 EX DC HSM has a focal range of 10-20mm and
2.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
16-32mm when used on a APS-C / DX format camera.
On the other hand, the Tamron 10-24mm f3.5-4.5 II LD has a focal range of 10-24mm and 2.4X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 16-38.4mm when used on a APS-C / DX format camera.