The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 24mm F3.5 DG DN C and the Tamron 20mm F2.8 Di III OSD M1:2 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 20mm F2.8 Di III OSD M1:2 is the longer of the two lenses at 64mm. The Sigma 24mm F3.5 DG DN C with a length of 49mm, is 15mm shorter. Besides being longer, the Tamron 20mm F2.8 Di III OSD M1:2 also has a larger diameter of 73mm compared to the Sigma 24mm F3.5 DG DN C's 64mm 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 20mm F2.8 Di III OSD M1:2 weighs 220g, 2% (5g) lighter than the Sigma 24mm F3.5 DG DN C's weight of 225g.
Filter Threads
The Sigma 24mm F3.5 DG DN C has a filter size of 55mm whereas the Tamron 20mm F2.8 Di III OSD M1:2 has a 67mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 55mm filters that we recommend you to consider for the Sigma 24mm F3.5 DG DN C:
And these are the 67mm filters that we recommend for the Tamron 20mm F2.8 Di III OSD M1:2:
Lens Mounts
Both the Sigma 24mm F3.5 DG DN C and the Tamron 20mm F2.8 Di III OSD M1:2 has the same Sony E lens mount. Some of the latest released cameras that are compatible with the Sony E lenses are Sony A9 III, Sony A7C Mark II and Sony A7CR.
Sigma 24mm F3.5 DG DN C is also available in Leica L mount.
Focal Range
Sigma 24mm F3.5 DG DN C is a prime lens with fixed focal lenght of 24mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
36mm.
On the other hand, the Tamron 20mm F2.8 Di III OSD M1:2 is a prime lens with fixed focal lenght of 20mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 30mm.