The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Fujifilm XF 150-600mm F5.6-8 R and the Samyang 300mm f6.3 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. Fujifilm XF 150-600mm F5.6-8 R is the longer of the two lenses at 315mm. The Samyang 300mm f6.3 with a length of 74mm, is 241mm shorter. Besides being longer, the Fujifilm XF 150-600mm F5.6-8 R also has a larger diameter of 99mm compared to the Samyang 300mm f6.3's 65mm 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. Samyang 300mm f6.3 weighs 318g, 80% (1287g) lighter than the Fujifilm XF 150-600mm F5.6-8 R's weight of 1605g.
Lens Mounts
Both the Fujifilm XF 150-600mm F5.6-8 R and the Samyang 300mm f6.3 has the same Fujifilm X lens mount. Some of the latest released cameras that are compatible with the Fujifilm X lenses are Fujifilm X-T30 III, Fujifilm X-E5 and Fujifilm X-M5.
Samyang 300mm f6.3 is also available in Canon EF-M , Micro Four Thirds and Sony E mounts.
Focal Range
Fujifilm XF 150-600mm F5.6-8 R has a focal range of 150-600mm and
4.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
225-900mm when used on a APS-C / DX format camera.
On the other hand, the Samyang 300mm f6.3 is a prime lens with fixed focal lenght of 300mm which has an effective (full-frame 35mm equivalent) focal range of 450mm when used on a APS-C / DX format camera.