The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 85mm F1.4 DG HSM and the Tamron 85mm F1.8 VC for their suitability to various photography scenarios:
Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Sigma 85mm F1.4 DG HSM is the longer of the two lenses at 126mm. The Tamron 85mm F1.8 VC with a length of 91mm is 35mm shorter. Besides being longer, the Sigma 85mm F1.4 DG HSM also has a larger diameter of 95mm compared to Tamron 85mm F1.8 VC's 85mm diameter.
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. Tamron 85mm F1.8 VC weighs 700g, 38% (430g) lighter than the Sigma 85mm F1.4 DG HSM's weight of 1130g.
Below you can find the dimension and weight table of the 'Telephoto Prime Lenses in Nikon F (FX) Mount for size comparison purposes.
Telephoto Prime Lenses in Nikon F (FX) Mount for Size Comparison
Lens Mounts
Both Sigma 85mm F1.4 DG HSM and Tamron 85mm F1.8 VC has the same Nikon F (FX) lens mount. Some of the latest released cameras that are compatible with the Nikon F (FX) lenses are Nikon D6, Nikon D780 and Nikon D3500.
Sigma 85mm F1.4 DG HSM is also available in Sigma SA and Canon EF mounts.
Tamron 85mm F1.8 VC is also available in Sony Alpha and Canon EF mounts.
Focal Range