The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 19mm F2.8 DN and the Tokina Firin 20mm F2 FE MF for their suitability to various photography scenarios:
Size and Weight Comparison
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 19mm F2.8 DN weighs 140g, which means it is 350g (71%) lighter than the Tokina Firin 20mm F2 FE MF which has a weight of 490g.
Lens Mounts
Both the Sigma 19mm F2.8 DN 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 A6700, Sony FX30 and Sony ZV-E10.
Sigma 19mm F2.8 DN is also available in Micro Four Thirds mount.
Tokina Firin 20mm F2 FE MF is also available in Sony E mount.
Focal Range
Sigma 19mm F2.8 DN is a prime lens with fixed focal lenght of 19mm which has an effective (full-frame 35mm equivalent) focal range of
28.5mm when used on a APS-C / DX format camera.
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.