The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Samyang 20mm F1.8 and the Fujifilm 27mm F2.8 for their suitability to various photography scenarios:
Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Samyang 20mm F1.8 is the longer of the two lenses at 88mm. The Fujifilm 27mm F2.8 with a length of 23mm is 65mm shorter. Besides being longer, the Samyang 20mm F1.8 also has a larger diameter of 83mm compared to Fujifilm 27mm F2.8's 61mm diameter.
Weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Fujifilm 27mm F2.8 weighs 78g, 84% (419g) lighter than the Samyang 20mm F1.8's weight of 497g.
Below you can find the dimension and weight table of the 'Wideangle Prime Lenses in Fujifilm X Mount for size comparison purposes.
Wideangle Prime Lenses in Fujifilm X Mount for Size Comparison
Lens Mounts
Both Samyang 20mm F1.8 and Fujifilm 27mm F2.8 has the same Fujifilm X lens mount. Some of the latest released cameras that are compatible with the Fujifilm X lenses are Fujifilm X-T5, Fujifilm X-H2 and Fujifilm X-H2S.
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
Samyang 20mm F1.8 is a prime lens with fixed focal lenght of 20mm. Fujifilm 27mm F2.8 is a prime lens with fixed focal lenght of 27mm which has an effective (full-frame 35mm equivalent) focal range of 40.5mm when used on a APS-C / DX format camera.