The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 50-100mm F1.8 A and the Nikon 55-200mm f4-5.6G ED 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 50-100mm F1.8 A is the longer of the two lenses at 171mm. The Nikon 55-200mm f4-5.6G ED with a length of 79mm, is 92mm shorter. Besides being longer, the Sigma 50-100mm F1.8 A also has a larger diameter of 94mm compared to the Nikon 55-200mm f4-5.6G ED's 68mm 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 55-200mm f4-5.6G ED weighs 255g, 82% (1235g) lighter than the Sigma 50-100mm F1.8 A's weight of 1490g.
Below you can find the dimension and weight table of the Telephoto Zoom Lenses in Nikon F (DX) Mount for size comparison purposes.
Telephoto Lenses in Nikon F (DX) Mount for Size Comparison
Filter Threads
The Sigma 50-100mm F1.8 A has a filter size of 82mm whereas the Nikon 55-200mm f4-5.6G ED has a 52mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 82mm filters that we recommend you to consider for the Sigma 50-100mm F1.8 A:
And these are the 52mm filters that we recommend for the Nikon 55-200mm f4-5.6G ED:
Lens Mounts
Both the Sigma 50-100mm F1.8 A and the Nikon 55-200mm f4-5.6G ED has the same Nikon F (DX) lens mount. Some of the latest released cameras that are compatible with the Nikon F (DX) lenses are Nikon D3500, Nikon D7500 and Nikon D5600.
Sigma 50-100mm F1.8 A is also available in Canon EF and Sigma SA mounts.
Focal Range
Sigma 50-100mm F1.8 A has a focal range of 50-100mm and
2.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
75-150mm when used on a APS-C / DX format camera.
On the other hand, the Nikon 55-200mm f4-5.6G ED has a focal range of 55-200mm and 3.6X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 82.5-300mm when used on a APS-C / DX format camera.