The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Samyang 21mm F1.4 ED AS UMC CS and the Fujifilm XF 27mm F2.8 R WR 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 21mm F1.4 ED AS UMC CS is the longer of the two lenses at 68mm. The Fujifilm XF 27mm F2.8 R WR with a length of 23mm, is 45mm shorter. Besides being longer, the Samyang 21mm F1.4 ED AS UMC CS also has a larger diameter of 64mm compared to the Fujifilm XF 27mm F2.8 R WR's 62mm diameter.
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Below you can find a scaled side-by-side image of Samyang 21mm F1.4 ED AS UMC CS and Fujifilm XF 27mm F2.8 R WR to get a better idea of how their sizes compare in real life.
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. Fujifilm XF 27mm F2.8 R WR weighs 84g, 69% (191g) lighter than the Samyang 21mm F1.4 ED AS UMC CS's weight of 275g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Fujifilm X Mount for size comparison purposes.
Wideangle Lenses in Fujifilm X Mount for Size Comparison
Filter Threads
The Samyang 21mm F1.4 ED AS UMC CS has a filter size of 58mm whereas the Fujifilm XF 27mm F2.8 R WR has a 39mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 58mm filters that we recommend you to consider for the Samyang 21mm F1.4 ED AS UMC CS:
And these are the 39mm filters that we recommend for the Fujifilm XF 27mm F2.8 R WR:
Lens Mounts
Both the Samyang 21mm F1.4 ED AS UMC CS and the Fujifilm XF 27mm F2.8 R WR has the same Fujifilm X lens mount. Some of the latest released cameras that are compatible with the Fujifilm X lenses are Fujifilm X-S20, Fujifilm X-T5 and Fujifilm X-H2.
Samyang 21mm F1.4 ED AS UMC CS is also available in Canon EF-M , Micro Four Thirds and Sony E mounts.
Focal Range
Samyang 21mm F1.4 ED AS UMC CS is a prime lens with fixed focal lenght of 21mm which has an effective (full-frame 35mm equivalent) focal range of
31.5mm when used on a APS-C / DX format camera.
On the other hand, the Fujifilm XF 27mm F2.8 R WR 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.