The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Tamron 85mm F1.8 VC and the Sony 85mm F2.8 SAM for their suitability to various photography scenarios:
Size and Weight Comparison
Size of a lens is an important deciding factor when comparing two lenses.Tamron 85mm F1.8 VC is the longer of the two lenses at 91mm. The Sony 85mm F2.8 SAM with a length of 52mm is 39mm shorter. Besides being longer, the Tamron 85mm F1.8 VC also has a larger diameter of 85mm compared to Sony 85mm F2.8 SAM's 70mm 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. Sony 85mm F2.8 SAM weighs 175g, 75% (525g) lighter than the Tamron 85mm F1.8 VC's weight of 700g.
Below you can find the dimension and weight table of the 'Telephoto Prime Lenses in Sony Alpha Mount for size comparison purposes.
Telephoto Prime Lenses in Sony Alpha Mount for Size Comparison
Both Tamron 85mm F1.8 VC and Sony 85mm F2.8 SAM has the same Sony Alpha lens mount. Some of the latest released cameras that are compatible with the Sony Alpha lenses are Sony A99 II, Sony A68 and Sony A77 II.
Tamron 85mm F1.8 VC is also available in Canon EF and Nikon F (FX) mounts.