The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 105mm F2.8 EX DG OS HSM and the Nikon 85mm f1.8D 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 105mm F2.8 EX DG OS HSM is the longer of the two lenses at 127mm. The Nikon 85mm f1.8D with a length of 59mm, is 68mm shorter. Besides being longer, the Sigma 105mm F2.8 EX DG OS HSM also has a larger diameter of 78mm compared to the Nikon 85mm f1.8D's 72mm 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 85mm f1.8D weighs 380g, 47% (346g) lighter than the Sigma 105mm F2.8 EX DG OS HSM's weight of 726g.
Filter Threads
Both the Sigma 105mm F2.8 EX DG OS HSM and the Nikon 85mm f1.8D have the same Filter thread size of 62mm.
Below are links to the 62mm filters that we recommend you to consider for these lenses:
Lens Mounts
Both the Sigma 105mm F2.8 EX DG OS HSM and the Nikon 85mm f1.8D has the same Nikon F (FX) lens mount. Some of the latest released cameras that are compatible with the Nikon F (FX) lenses are Nikon D6, Nikon D780 and Nikon D3500.
Sigma 105mm F2.8 EX DG OS HSM is also available in Canon EF and Sigma SA mounts.
Focal Range
Sigma 105mm F2.8 EX DG OS HSM is a prime lens with fixed focal lenght of 105mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
157.5mm.
On the other hand, the Nikon 85mm f1.8D is a prime lens with fixed focal lenght of 85mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 127.5mm.