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
The size of a lens is a crucial factor to consider 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 the Sony 85mm F2.8 SAM's 70mm diameter.
The weight of a lens is equally significant as its external dimensions, particularly if you intend to handhold your camera and lens combination for extended 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 Lenses in Sony Alpha Mount for Size Comparison
Filter Threads
The Venus 105mm F2 has a filter size of 67mm whereas the Sony 85mm F2.8 SAM has a 55mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 67mm filters that we recommend you to consider for the Venus 105mm F2:
And these are the 55mm filters that we recommend for the Sony 85mm F2.8 SAM:
Lens Mounts
Both the Venus 105mm F2 and the 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 a 35mm (FF) equivalent of
157.5mm.
On the other hand, the 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 a 35mm (FF) equivalent of 127.5mm.