The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sony 12-24mm F2.8 GM and the Tokina Firin 20mm F2 FE MF 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 12-24mm F2.8 GM is the longer of the two lenses at 137mm. The Tokina Firin 20mm F2 FE MF with a length of 82mm, is 55mm shorter. Besides being longer, the Sony 12-24mm F2.8 GM also has a larger diameter of 98mm compared to the Tokina Firin 20mm F2 FE MF's 69mm 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. Tokina Firin 20mm F2 FE MF weighs 490g, 42% (357g) lighter than the Sony 12-24mm F2.8 GM's weight of 847g.
Lens Mounts
Both the Sony 12-24mm F2.8 GM 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.
Tokina Firin 20mm F2 FE MF is also available in Sony E mount.
Focal Range
Sony 12-24mm F2.8 GM has a focal range of 12-24mm and
2.0X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
18 - 36mm.
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.