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 Pentax 50-200mm F4-5.6 ED WR 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 Pentax 50-200mm F4-5.6 ED WR with a length of 80mm, is 19mm shorter. Besides being longer, the Venus 105mm F2 also has a larger diameter of 76mm compared to the Pentax 50-200mm F4-5.6 ED WR's 69mm 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. Pentax 50-200mm F4-5.6 ED WR weighs 285g, 61% (460g) lighter than the Venus 105mm F2's weight of 745g.
Filter Threads
The Venus 105mm F2 has a filter size of 67mm whereas the Pentax 50-200mm F4-5.6 ED WR has a 49mm 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 49mm filters that we recommend for the Pentax 50-200mm F4-5.6 ED WR:
Lens Mounts
The Venus 105mm F2 has the Pentax KAF2 lens mount whereas the Pentax 50-200mm F4-5.6 ED WR has the Pentax KAF lens mount. Some of the latest released cameras that are compatible with these mounts are Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF2 Mount and Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF Mount.
Venus 105mm F2 is also available in the Sony E , Canon EF, Nikon F (FX) and Sony Alpha 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 Pentax 50-200mm F4-5.6 ED WR has a focal range of 50-200mm and 4.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 75-300mm when used on a APS-C / DX format camera.
