The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sony 75-300mm F4.5-5.6 and the Sigma 70-300mm F4-5.6 DG for their suitability to various photography scenarios:
Size and Weight Comparison
The 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. Sony 75-300mm F4.5-5.6 weighs 460g, which means it is 90g (16%) lighter than the Sigma 70-300mm F4-5.6 DG which has a weight of 550g.
Below you can find the dimension and weight table of the Telephoto Zoom Lenses in Sony Alpha Mount for size comparison purposes.
Telephoto Zoom Lenses in Sony Alpha Mount for Size Comparison
Lens Mounts
Both the Sony 75-300mm F4.5-5.6 and the Sigma 70-300mm F4-5.6 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 70-300mm F4-5.6 DG is also available in Canon EF , Nikon F (FX), Pentax KAF, Sigma SA, Canon EF, Nikon F (FX), Pentax KAF, Sony Alpha and Sigma SA mounts.
Focal Range
Sony 75-300mm F4.5-5.6 has a focal range of 75-300mm and 4.0X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 112.5 - 450mm.
Sigma 70-300mm F4-5.6 DG has a focal range of 70-300mm and 4.3X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 105 - 450mm.