The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 50-200mm F4-5.6 DC OS HSM and the Nikon 85mm f1.8G 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 50-200mm F4-5.6 DC OS HSM is the longer of the two lenses at 102mm. The Nikon 85mm f1.8G with a length of 73mm, is 29mm shorter. On the other hand, the Nikon 85mm f1.8G has a larger diameter of 80mm compared to the Sigma 50-200mm F4-5.6 DC OS HSM's 74mm 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 f1.8G weighs 350g, 16% (70g) lighter than the Sigma 50-200mm F4-5.6 DC OS HSM's weight of 420g.
Filter Threads
The Sigma 50-200mm F4-5.6 DC OS HSM has a filter size of 55mm whereas the Nikon 85mm f1.8G 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 55mm filters that we recommend you to consider for the Sigma 50-200mm F4-5.6 DC OS HSM:
And these are the 67mm filters that we recommend for the Nikon 85mm f1.8G:
Lens Mounts
The Sigma 50-200mm F4-5.6 DC OS HSM has the Nikon F (DX) lens mount whereas the Nikon 85mm f1.8G has the Nikon F (FX) lens mount. Some of the latest released cameras that are compatible with these mounts are Nikon D3500, Nikon D7500 and Nikon D5600 for the Nikon F (DX) Mount and Nikon D6, Nikon D780 and Nikon D3500 for the Nikon F (FX) Mount.
Sigma 50-200mm F4-5.6 DC OS HSM is also available in the Canon EF , Pentax KAF3, Sony Alpha and Sigma SA mounts.
Focal Range
Sigma 50-200mm F4-5.6 DC OS HSM has a focal range of 50-200mm and
4.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
75-300mm when used on a APS-C / DX format camera.
On the other hand, the Nikon 85mm f1.8G 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.
