The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 18-50mm F2.8-4.5 DC OS HSM and the Fujifilm 18mm F2 R 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. Sigma 18-50mm F2.8-4.5 DC OS HSM is the longer of the two lenses at 89mm. The Fujifilm 18mm F2 R with a length of 41mm, is 48mm shorter. Besides being longer, the Sigma 18-50mm F2.8-4.5 DC OS HSM also has a larger diameter of 74mm compared to the Fujifilm 18mm F2 R'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. Fujifilm 18mm F2 R weighs 116g, 70% (279g) lighter than the Sigma 18-50mm F2.8-4.5 DC OS HSM's weight of 395g.
Lens Mounts
The Sigma 18-50mm F2.8-4.5 DC OS HSM has the Canon EF lens mount whereas the Fujifilm 18mm F2 R has the Fujifilm X lens mount. Some of the latest released cameras that are compatible with these mounts are Canon T8i, Canon 90D and Canon SL3 for the Canon EF Mount and Fujifilm X-T30 III, Fujifilm X-E5 and Fujifilm X-M5 for the Fujifilm X Mount.
Sigma 18-50mm F2.8-4.5 DC OS HSM is also available in the Pentax KAF3 , Sony Alpha, Sigma SA and Nikon F (DX) mounts.
Focal Range
Sigma 18-50mm F2.8-4.5 DC OS HSM has a focal range of 18-50mm and
2.8X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
28.8-80mm when used on a APS-C / DX format camera.
On the other hand, the Fujifilm 18mm F2 R is a prime lens with fixed focal lenght of 18mm which has an effective (full-frame 35mm equivalent) focal range of 27mm when used on a APS-C / DX format camera.
