The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sony DT 16-50mm F2.8 SSM and the Sigma 24mm F1.8 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. Sony DT 16-50mm F2.8 SSM is the longer of the two lenses at 88mm. The Sigma 24mm F1.8 EX DG with a length of 83mm, is 5mm shorter. On the other hand, the Sigma 24mm F1.8 EX DG has a larger diameter of 84mm compared to the Sony DT 16-50mm F2.8 SSM's 81mm 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 24mm F1.8 EX DG weighs 500g, 13% (77g) lighter than the Sony DT 16-50mm F2.8 SSM's weight of 577g.
Filter Threads
The Sony DT 16-50mm F2.8 SSM has a filter size of 72mm whereas the Sigma 24mm F1.8 EX DG has a 77mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 72mm filters that we recommend you to consider for the Sony DT 16-50mm F2.8 SSM:
And these are the 77mm filters that we recommend for the Sigma 24mm F1.8 EX DG:
Lens Mounts
The Sony DT 16-50mm F2.8 SSM has the Sony Alpha lens mount whereas the Sigma 24mm F1.8 EX DG has the Pentax KAF lens mount. Some of the latest released cameras that are compatible with these mounts are Sony A68, Sony A77 II and Sony A58 for the Sony Alpha Mount and Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF Mount.
Sigma 24mm F1.8 EX DG is also available in Canon EF , Nikon F (FX), Four Thirds, Pentax KAF, Sony Alpha, Sigma SA, Canon EF, Sony Alpha, Sigma SA and Nikon F (FX) mounts.
Focal Range
Sony DT 16-50mm F2.8 SSM has a focal range of 16-50mm and
3.1X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
24-75mm when used on a APS-C / DX format camera.
On the other hand, the Sigma 24mm F1.8 EX DG is a prime lens with fixed focal lenght of 28mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 42mm.