The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 24-70mm F2.8 DG OS HSM and the Sigma 24-105mm F4 DG OS 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 24-105mm F4 DG OS HSM is the longer of the two lenses at 109mm. The Sigma 24-70mm F2.8 DG OS HSM with a length of 108mm, is 1mm shorter. Besides being longer, the Sigma 24-105mm F4 DG OS HSM also has a larger diameter of 89mm compared to the Sigma 24-70mm F2.8 DG OS HSM's 88mm 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. Sigma 24-105mm F4 DG OS HSM weighs 885g, 13% (135g) lighter than the Sigma 24-70mm F2.8 DG OS HSM's weight of 1020g.
Filter Threads
Both the Sigma 24-70mm F2.8 DG OS HSM and the Sigma 24-105mm F4 DG OS HSM have the same Filter thread size of 82mm.
Below are links to the 82mm filters that we recommend you to consider for these lenses:
Lens Mounts
The Sigma 24-70mm F2.8 DG OS HSM has the Sigma SA lens mount whereas the Sigma 24-105mm F4 DG OS HSM has the Sony Alpha lens mount. Some of the latest released cameras that are compatible with these mounts are Sigma Quattro, Sigma Quattro H and Sigma SD1 Merrill for the Sigma SA Mount and Sony A99 II, Sony A68 and Sony A77 II for the Sony Alpha Mount.
Sigma 24-70mm F2.8 DG OS HSM is also available in Nikon F (FX) and Canon EF mounts.
Sigma 24-105mm F4 DG OS HSM is also available in Canon EF , Nikon F (FX) and Sigma SA mounts.
Focal Range
Sigma 24-70mm F2.8 DG OS HSM has a focal range of 24-70mm and
2.9X zoom ratio .
On the other hand, the Sigma 24-105mm F4 DG OS HSM has a focal range of 24-105mm and 4.4X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 36 - 157.5mm.