The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Nikon 20mm f2.8D and the Nikon DX Fisheye-10.5mm f2.8G 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. Nikon DX Fisheye-10.5mm f2.8G ED is the longer of the two lenses at 63mm. The Nikon 20mm f2.8D with a length of 43mm, is 20mm shorter. On the other hand, the Nikon 20mm f2.8D has a larger diameter of 69mm compared to the Nikon DX Fisheye-10.5mm f2.8G ED's 63mm 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 f2.8D weighs 270g, which means it is 30g (9%) lighter than the Nikon DX Fisheye-10.5mm f2.8G ED which has a weight of 300g.
Lens Mounts
The Nikon 20mm f2.8D has the Nikon F (FX) lens mount whereas the Nikon DX Fisheye-10.5mm f2.8G 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 D3500, Nikon D7500 and Nikon D5600 for the Nikon F (DX) Mount.
Focal Range
Nikon 20mm f2.8D is a prime lens with fixed focal lenght of 20mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
30mm.
On the other hand, the Nikon DX Fisheye-10.5mm f2.8G ED is a prime lens with fixed focal lenght of 11mm which has an effective (full-frame 35mm equivalent) focal range of 16.5mm when used on a APS-C / DX format camera.
