The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 500mm F4 DG OS HSM Sport and the Canon 85mm f1.2L II USM 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. Sigma 500mm F4 DG OS HSM Sport is the longer of the two lenses at 380mm. The Canon 85mm f1.2L II USM with a length of 84mm, is 296mm shorter. Besides being longer, the Sigma 500mm F4 DG OS HSM Sport also has a larger diameter of 145mm compared to the Canon 85mm f1.2L II USM's 92mm 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. Canon 85mm f1.2L II USM weighs 1025g, 69% (2285g) lighter than the Sigma 500mm F4 DG OS HSM Sport's weight of 3310g.
Below you can find the dimension and weight table of the Telephoto Prime Lenses in Canon EF Mount for size comparison purposes.
Telephoto Prime Lenses in Canon EF Mount for Size Comparison
Lens Mounts
Both the Sigma 500mm F4 DG OS HSM Sport and the Canon 85mm f1.2L II USM 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.
Sigma 500mm F4 DG OS HSM Sport is also available in Sigma SA and Nikon F (FX) mounts.
Focal Range
Sigma 500mm F4 DG OS HSM Sport is a prime lens with fixed focal lenght of 500mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 800mm.
Canon 85mm f1.2L II USM is a prime lens with fixed focal lenght of 85mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 136mm.