The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 12mm f1.4 and the Samyang 20mm F1.8 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. Samyang 20mm F1.8 is the longer of the two lenses at 88mm. The Sigma 12mm f1.4 with a length of 69mm, is 19mm shorter. Besides being longer, the Samyang 20mm F1.8 also has a larger diameter of 83mm compared to the Sigma 12mm f1.4's 68mm 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 12mm f1.4 weighs 225g, which means it is 272g (54%) lighter than the Samyang 20mm F1.8 which has a weight of 497g.
Filter Threads
The Sigma 12mm f1.4 has a filter size of 62mm whereas the Samyang 20mm F1.8 has a 77mm 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 Sigma 12mm f1.4:
And these are the 77mm filters that we recommend for the Samyang 20mm F1.8:
Lens Mounts
The Sigma 12mm f1.4 has the Sony E lens mount whereas the Samyang 20mm F1.8 has the Fujifilm X lens mount. Some of the latest released cameras that are compatible with these mounts are Sony ZV-E10 II, Sony A6700 and Sony FX30 for the Sony E Mount and Fujifilm X-T30 III, Fujifilm X-E5 and Fujifilm X-M5 for the Fujifilm X Mount.
Sigma 12mm f1.4 is also available in the Fujifilm X and Canon RF mounts.
Samyang 20mm F1.8 is also available in Canon EF , Canon EF-M, Micro Four Thirds, Nikon F (FX), Pentax KAF, Samsung NX, Sony Alpha and Sony E mounts.
Focal Range
Sigma 12mm f1.4 is a prime lens with fixed focal lenght of 12mm which has an effective (full-frame 35mm equivalent) focal range of
18mm when used on a APS-C / DX format camera.
On the other hand, the Samyang 20mm F1.8 is a prime lens with fixed focal lenght of 20mm.
