The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tokina AT-X 14-20mm F2 Pro DX and the Samyang 16mm f2.0 for their suitability to various photography scenarios:
Size and Weight Comparison
The size of a lens is an important deciding factor when comparing two lenses. Tokina AT-X 14-20mm F2 Pro DX is the longer of the two lenses at 106mm. The Samyang 16mm f2.0 with a length of 89mm, is 17mm shorter. Besides being longer, the Tokina AT-X 14-20mm F2 Pro DX also has a larger diameter of 89mm compared to the Samyang 16mm f2.0's 83mm diameter.
The weight of a lens is as important as its external dimensions, especially if you are planning to hand hold your camera and lens combination for longer periods. Samyang 16mm f2.0 weighs 583g, 19% (142g) lighter than the Tokina AT-X 14-20mm F2 Pro DX's weight of 725g.
Lens Mounts
Both the Tokina AT-X 14-20mm F2 Pro DX and the Samyang 16mm f2.0 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.
Tokina AT-X 14-20mm F2 Pro DX is also available in Canon EF mount.
Samyang 16mm f2.0 is also available in Canon EF , Canon EF-M, Fujifilm X, Four Thirds, Micro Four Thirds, Pentax KAF, Sony Alpha, Sony E and Samsung NX mounts.
Focal Range
Tokina AT-X 14-20mm F2 Pro DX has a focal range of 14-20mm and 1.4X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 21-30mm when used on a APS-C / DX format camera. Samyang 16mm f2.0 is a prime lens with fixed focal lenght of 16mm which has an effective (full-frame 35mm equivalent) focal range of 24mm when used on a APS-C / DX format camera.