The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron 28-75mm F2.8 Di III and the Sigma 24-70mm F2.8 EX 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. Tamron 28-75mm F2.8 Di III is the longer of the two lenses at 118mm. The Sigma 24-70mm F2.8 EX DG HSM with a length of 95mm, is 23mm shorter. On the other hand, the Sigma 24-70mm F2.8 EX DG HSM has a larger diameter of 89mm compared to the Tamron 28-75mm F2.8 Di III's 76mm 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 28-75mm F2.8 Di III weighs 540g, which means it is 250g (31%) lighter than the Sigma 24-70mm F2.8 EX DG HSM which has a weight of 790g.
Filter Threads
The Tamron 28-75mm F2.8 Di III has a filter size of 67mm whereas the Sigma 24-70mm F2.8 EX DG HSM has a 82mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 67mm filters that we recommend you to consider for the Tamron 28-75mm F2.8 Di III:
And these are the 82mm filters that we recommend for the Sigma 24-70mm F2.8 EX DG HSM:
Lens Mounts
The Tamron 28-75mm F2.8 Di III has the Sony E lens mount whereas the Sigma 24-70mm F2.8 EX DG HSM has the Pentax KAF3 lens mount. Some of the latest released cameras that are compatible with these mounts are Sony FX5, Sony A7R VI and Sony A7 V for the Sony E Mount and , and for the Pentax KAF3 Mount.
Tamron 28-75mm F2.8 Di III is also available in the Sony E and Nikon Z mounts.
Sigma 24-70mm F2.8 EX DG HSM is also available in Canon EF , Sony Alpha, Sigma SA and Nikon F (FX) mounts.
Focal Range
Tamron 28-75mm F2.8 Di III has a focal range of 28-75mm and
2.7X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
42 - 112.5mm.
On the other hand, the Sigma 24-70mm F2.8 EX DG HSM 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 a 35mm (FF) equivalent of 36 - 105mm.
