The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron 10-24mm f3.5-4.5 II LD and the Sigma 12-24mm F4.5-5.6 II DG HSM 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 12-24mm F4.5-5.6 II DG HSM is the longer of the two lenses at 120mm. The Tamron 10-24mm f3.5-4.5 II LD with a length of 84mm, is 36mm shorter. Besides being longer, the Sigma 12-24mm F4.5-5.6 II DG HSM also has a larger diameter of 87mm 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, which means it is 264g (39%) lighter than the Sigma 12-24mm F4.5-5.6 II DG HSM which has a weight of 670g.
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
Lens Mounts
Both the Tamron 10-24mm f3.5-4.5 II LD and the Sigma 12-24mm F4.5-5.6 II DG HSM 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.
Tamron 10-24mm f3.5-4.5 II LD is also available in Nikon F (DX) , Sony Alpha, Pentax KAF and Canon EF mounts.
Sigma 12-24mm F4.5-5.6 II DG HSM is also available in Sigma SA and Nikon F (FX) mounts.
Focal Range
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.
On the other hand, the Sigma 12-24mm F4.5-5.6 II DG HSM has a focal range of 12-24mm and 2.0X zoom ratio . When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 19.2 - 38.4mm.