The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron 17-50mm f2.8 XR II LD and the Sony 24-70mm F2.8 ZA SSM for their suitability to various photography scenarios:
Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Sony 24-70mm F2.8 ZA SSM is the longer of the two lenses at 111mm. The Tamron 17-50mm f2.8 XR II LD with a length of 82mm is 29mm shorter. Besides being longer, the Sony 24-70mm F2.8 ZA SSM also has a larger diameter of 83mm compared to Tamron 17-50mm f2.8 XR II LD's 74mm 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. Tamron 17-50mm f2.8 XR II LD weighs 430g, which means it is 525g (54%) lighter than the Sony 24-70mm F2.8 ZA SSM which has a 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 Tamron 17-50mm f2.8 XR II LD and Sony 24-70mm F2.8 ZA SSM has the same Sony Alpha lens mount. Some of the latest released cameras that are compatible with the Sony Alpha lenses are Sony A68, Sony A77 II and Sony A58.
Tamron 17-50mm f2.8 XR II LD is also available in Canon EF , Nikon F (DX) and Pentax KAF mounts.
Tamron 17-50mm f2.8 XR II LD has a focal range of 17-50mm and 2.9X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 25.5-75mm when used on a APS-C / DX format camera. Sony 24-70mm F2.8 ZA SSM has a focal range of 24-70mm and 2.9X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides an 35mm (FF) equivalent of 36 - 105mm.