Size and Weight Comparison
The size of a lens is a crucial factor to consider when comparing two lenses. Tokina Firin 20mm F2 FE MF is the longer of the two lenses at 82mm. The Sigma 17mm F4 DG DN C with a length of 51mm, is 31mm shorter. Besides being longer, the Tokina Firin 20mm F2 FE MF also has a larger diameter of 69mm compared to the Sigma 17mm F4 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. Sigma 17mm F4 DG DN C weighs 220g, which means it is 270g (55%) lighter than the Tokina Firin 20mm F2 FE MF which has a weight of 490g.
Filter Threads
The Sigma 17mm F4 DG DN C has a filter size of 55mm whereas the Tokina Firin 20mm F2 FE MF has a 62mm 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 17mm F4 DG DN C:
And these are the 62mm filters that we recommend for the Tokina Firin 20mm F2 FE MF:
Lens Mounts
Both the Sigma 17mm F4 DG DN C and the Tokina Firin 20mm F2 FE MF has the same Sony E lens mount. Some of the latest released cameras that are compatible with the Sony E lenses are Sony FX5, Sony A7R VI and Sony A7 V.
Sigma 17mm F4 DG DN C is also available in the Leica L mount.
Tokina Firin 20mm F2 FE MF is also available in Sony E mount.
Focal Range
Sigma 17mm F4 DG DN C is a prime lens with fixed focal lenght of 17mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
25.5mm.
On the other hand, the Tokina Firin 20mm F2 FE MF 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.
