The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sony 24-70mm F2.8 ZA SSM and the Sigma 24-70mm F2.8 EX DG for their suitability to various photography scenarios:
Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Sigma 24-70mm F2.8 EX DG is the longer of the two lenses at 116mm. The Sony 24-70mm F2.8 ZA SSM with a length of 111mm is 5mm shorter. Besides being longer, the Sigma 24-70mm F2.8 EX DG also has a larger diameter of 89mm compared to Sony 24-70mm F2.8 ZA SSM's 83mm diameter.
Weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Sigma 24-70mm F2.8 EX DG weighs 715g, 25% (240g) lighter than the Sony 24-70mm F2.8 ZA SSM's weight of 955g.
Below you can find the dimension and weight table of the 'Standard Zoom Lenses in Sony Alpha Mount for size comparison purposes.
Standard Zoom Lenses in Sony Alpha Mount for Size Comparison
Both Sony 24-70mm F2.8 ZA SSM and Sigma 24-70mm F2.8 EX DG 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 24-70mm F2.8 EX DG is also available in Canon EF , Pentax KAF, Sigma SA and Nikon F (FX) mounts.
Both lenses have the same focal range of 24-70mm and the fastest aperture of F2.8.