The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sony DT 50mm F1.8 SAM and the Sigma 24-70mm F2.8 EX DG 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 24-70mm F2.8 EX DG is the longer of the two lenses at 116mm. The Sony DT 50mm F1.8 SAM with a length of 45mm, is 71mm shorter. Besides being longer, the Sigma 24-70mm F2.8 EX DG also has a larger diameter of 89mm compared to the Sony DT 50mm F1.8 SAM's 70mm 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. Sony DT 50mm F1.8 SAM weighs 170g, which means it is 545g (76%) lighter than the Sigma 24-70mm F2.8 EX DG which has a weight of 715g.
Filter Threads
The Sony DT 50mm F1.8 SAM has a filter size of 49mm whereas the Sigma 24-70mm F2.8 EX DG 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 49mm filters that we recommend you to consider for the Sony DT 50mm F1.8 SAM:
And these are the 82mm filters that we recommend for the Sigma 24-70mm F2.8 EX DG:
Lens Mounts
Both the Sony DT 50mm F1.8 SAM and the 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 A68, Sony A77 II and Sony A58.
Sigma 24-70mm F2.8 EX DG is also available in Canon EF , Pentax KAF, Sigma SA and Nikon F (FX) mounts.
Focal Range
Sony DT 50mm F1.8 SAM is a prime lens with fixed focal lenght of 50mm which has an effective (full-frame 35mm equivalent) focal range of
75mm when used on a APS-C / DX format camera.
On the other hand, the Sigma 24-70mm F2.8 EX DG 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.
