The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Venus 105mm F2 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.Venus 105mm F2 is the longer of the two lenses at 99mm. The Sony 85mm F2.8 SAM with a length of 52mm is 47mm shorter. Besides being longer, the Venus 105mm F2 also has a larger diameter of 76mm 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, 76% (570g) lighter than the Venus 105mm F2's weight of 745g.
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
Lens Mounts
Both Venus 105mm F2 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.
Venus 105mm F2 is also available in Sony E , Canon EF, Nikon F (FX) and Pentax KAF2 mounts.
Focal Range
Venus 105mm F2 is a prime lens with fixed focal lenght of 105mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides an 35mm (FF) equivalent of 157.5mm.
Sony 85mm F2.8 SAM is a prime lens with fixed focal lenght of 85mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides an 35mm (FF) equivalent of 127.5mm.