The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 12-24mm F4.5-5.6 EX DG HSM and the Sigma 10-20mm F3.5 EX DC 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 EX DG HSM is the longer of the two lenses at 103mm. The Sigma 10-20mm F3.5 EX DC HSM with a length of 88mm, is 15mm shorter. On the other hand, there is no difference between the max diameters of these lenses, both coming at 87mm.
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 10-20mm F3.5 EX DC HSM weighs 520g, 13% (80g) lighter than the Sigma 12-24mm F4.5-5.6 EX DG HSM's weight of 600g.
Below you can find the dimension and weight table of the Wideangle Zoom Lenses in Sony Alpha Mount for size comparison purposes.
Ultra-Wideangle Lenses in Sony Alpha Mount for Size Comparison
Lens Mounts
Both the Sigma 12-24mm F4.5-5.6 EX DG HSM and the Sigma 10-20mm F3.5 EX DC HSM has the same Sony Alpha lens mount. Some of the latest released cameras that are compatible with the Sony Alpha lenses are Sony A99 II, Sony A68 and Sony A77 II.
Sigma 12-24mm F4.5-5.6 EX DG HSM is also available in Canon EF , Pentax KAF, Sigma SA and Nikon F (FX) mounts.
Sigma 10-20mm F3.5 EX DC HSM is also available in Canon EF , Pentax KAF3, Sigma SA and Nikon F (DX) mounts.
Focal Range
Sigma 12-24mm F4.5-5.6 EX 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 1.5x crop, it provides a 35mm (FF) equivalent of
18 - 36mm.
On the other hand, the Sigma 10-20mm F3.5 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 15-30mm when used on a APS-C / DX format camera.