The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tokina Firin 20mm F2 FE MF and the ZEISS Loxia 21mm F2.8 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. ZEISS Loxia 21mm F2.8 is the longer of the two lenses at 72mm. The Tokina Firin 20mm F2 FE MF with a length of 69mm, is 3mm shorter. On the other hand, there is no difference between the max diameters of these lenses, both coming at 62mm.
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. ZEISS Loxia 21mm F2.8 weighs 394g, 19% (96g) lighter than the Tokina Firin 20mm F2 FE MF's weight of 490g.
Filter Threads
The Tokina Firin 20mm F2 FE MF has a filter size of 62mm whereas the ZEISS Loxia 21mm F2.8 has a 52mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 62mm filters that we recommend you to consider for the Tokina Firin 20mm F2 FE MF:
And these are the 52mm filters that we recommend for the ZEISS Loxia 21mm F2.8:
Lens Mounts
Both the Tokina Firin 20mm F2 FE MF and the ZEISS Loxia 21mm F2.8 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.
Tokina Firin 20mm F2 FE MF is also available in Sony E mount.
Focal Range
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.
On the other hand, the ZEISS Loxia 21mm F2.8 is a prime lens with fixed focal lenght of 21mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 31.5mm.