The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Rokinon 14mm f2.8 and the Carl Zeiss Distagon T2,8/21 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. Carl Zeiss Distagon T2,8/21 is the longer of the two lenses at 109mm. The Rokinon 14mm f2.8 with a length of 96mm, is 13mm shorter. On the other hand, there is no difference between the max diameters of these lenses, both coming at 87mm.
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. Rokinon 14mm f2.8 weighs 552g, which means it is 48g (7%) lighter than the Carl Zeiss Distagon T2,8/21 which has a weight of 600g.
Below you can find the dimension and weight table of the Wideangle Prime Lenses in Canon EF Mount for size comparison purposes.
Wideangle Prime Lenses in Canon EF Mount for Size Comparison
Lens Mounts
Both the Rokinon 14mm f2.8 and the Carl Zeiss Distagon T2,8/21 has the same Canon EF lens mount. Some of the latest released cameras that are compatible with the Canon EF lenses are Canon 1D X III, Canon 6D MII and Canon 5D MIV.
Rokinon 14mm f2.8 is also available in Nikon F (FX) , Four Thirds, Pentax KAF, Sony Alpha and Samsung NX mounts.
Carl Zeiss Distagon T2,8/21 is also available in Pentax KAF and Nikon F (FX) mounts.
Focal Range
Rokinon 14mm f2.8 is a prime lens with fixed focal lenght of 14mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 22.4mm.
Carl Zeiss Distagon T2,8/21 is a prime lens with fixed focal lenght of 21mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 33.6mm.