The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 20mm F1.4 DG HSM A and the Nikon 20mm f1.8G 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 20mm F1.4 DG HSM A is the longer of the two lenses at 130mm. The Nikon 20mm f1.8G ED with a length of 81mm, is 49mm shorter. Besides being longer, the Sigma 20mm F1.4 DG HSM A also has a larger diameter of 91mm compared to the Nikon 20mm f1.8G ED's 83mm 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 20mm f1.8G ED weighs 355g, 62% (595g) lighter than the Sigma 20mm F1.4 DG HSM A's weight of 950g.
Lens Mounts
The Sigma 20mm F1.4 DG HSM A has the Nikon F (FX) lens mount whereas the Nikon 20mm f1.8G ED has the Nikon F (DX) lens mount. Some of the latest released cameras that are compatible with these mounts are Nikon D6, Nikon D780 and Nikon D3500 for the Nikon F (FX) Mount and Nikon D6, Nikon D780 and Nikon D3500 for the Nikon F (DX) Mount.
Sigma 20mm F1.4 DG HSM A is also available in Canon EF , Sigma SA and Leica L mounts.
Focal Range
Both lenses have the same focal range of
20mm but while Sigma 20mm F1.4 DG HSM A has the fastest aperture of
F1.4, the Nikon 20mm f1.8G ED's widest aperture value is
F1.8.