The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Nikon Z 18-140mm f3.5-6.3 VR and the Sigma 17-70mm F2.8-4 DC OS HSM 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. Nikon Z 18-140mm f3.5-6.3 VR is the longer of the two lenses at 90mm. The Sigma 17-70mm F2.8-4 DC OS HSM with a length of 89mm, is 1mm shorter. On the other hand, the Sigma 17-70mm F2.8-4 DC OS HSM has a larger diameter of 79mm compared to the Nikon Z 18-140mm f3.5-6.3 VR's 73mm 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. Nikon Z 18-140mm f3.5-6.3 VR weighs 315g, which means it is 205g (39%) lighter than the Sigma 17-70mm F2.8-4 DC OS HSM which has a weight of 520g.
Filter Threads
The Nikon Z 18-140mm f3.5-6.3 VR has a filter size of 62mm whereas the Sigma 17-70mm F2.8-4 DC OS HSM has a 72mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 62mm filters that we recommend you to consider for the Nikon Z 18-140mm f3.5-6.3 VR:
And these are the 72mm filters that we recommend for the Sigma 17-70mm F2.8-4 DC OS HSM:
Lens Mounts
The Nikon Z 18-140mm f3.5-6.3 VR has the Nikon Z lens mount whereas the Sigma 17-70mm F2.8-4 DC OS HSM has the Pentax KAF3 lens mount. Some of the latest released cameras that are compatible with these mounts are RED Komodo-X 6K Z, Nikon Z50 II and Nikon Z30 for the Nikon Z Mount and , and for the Pentax KAF3 Mount.
Sigma 17-70mm F2.8-4 DC OS HSM is also available in Canon EF , Sony Alpha, Sigma SA and Nikon F (DX) mounts.
Focal Range
Nikon Z 18-140mm f3.5-6.3 VR has a focal range of 18-140mm and
7.8X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
27-210mm when used on a APS-C / DX format camera.
On the other hand, the Sigma 17-70mm F2.8-4 DC OS HSM has a focal range of 17-70mm and 4.1X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 25.5-105mm when used on a APS-C / DX format camera.
