The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Fujifilm XF 16-80mm F4 R OIS WR and the Sigma 18-50mm F2.8-4.5 DC OS HSM for their suitability to various photography scenarios:
Size and Weight Comparison
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 18-50mm F2.8-4.5 DC OS HSM weighs 395g, 10% (45g) lighter than the Fujifilm XF 16-80mm F4 R OIS WR's weight of 440g.
Filter Threads
The Fujifilm XF 16-80mm F4 R OIS WR has a filter size of 72mm whereas the Sigma 18-50mm F2.8-4.5 DC OS HSM has a 67mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 72mm filters that we recommend you to consider for the Fujifilm XF 16-80mm F4 R OIS WR:
And these are the 67mm filters that we recommend for the Sigma 18-50mm F2.8-4.5 DC OS HSM:
Lens Mounts
The Fujifilm XF 16-80mm F4 R OIS WR has the Fujifilm X lens mount whereas the Sigma 18-50mm F2.8-4.5 DC OS HSM has the Pentax KAF3 lens mount. Some of the latest released cameras that are compatible with these mounts are Fujifilm X-T30 III, Fujifilm X-E5 and Fujifilm X-M5 for the Fujifilm X Mount and , and for the Pentax KAF3 Mount.
Sigma 18-50mm F2.8-4.5 DC OS HSM is also available in Canon EF , Sony Alpha, Sigma SA and Nikon F (DX) mounts.
Focal Range
Fujifilm XF 16-80mm F4 R OIS WR has a focal range of 16-80mm and
5.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
24-120mm when used on a APS-C / DX format camera.
On the other hand, the 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 27-75mm when used on a APS-C / DX format camera.
