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 Venus 100mm F2.8 2X Ultra Macro 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 100mm F2.8 2X Ultra Macro is the longer of the two lenses at 125mm. The Venus 105mm F2 with a length of 99mm, is 26mm shorter. On the other hand, the Venus 105mm F2 has a larger diameter of 76mm compared to the Venus 100mm F2.8 2X Ultra Macro's 72mm diameter.
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Below you can find a scaled side-by-side image of Venus 105mm F2 and Venus 100mm F2.8 2X Ultra Macro to get a better idea of how their sizes compare in real life.
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. Venus 100mm F2.8 2X Ultra Macro weighs 638g, 14% (107g) lighter than the Venus 105mm F2's weight of 745g.
Filter Threads
Both the Venus 105mm F2 and the Venus 100mm F2.8 2X Ultra Macro have the same Filter thread size of 67mm.
Below are links to the 67mm filters that we recommend you to consider for these lenses:
Lens Mounts
Both the Venus 105mm F2 and the Venus 100mm F2.8 2X Ultra Macro has the same Pentax KAF2 lens mount. Some of the latest released cameras that are compatible with the Pentax KAF2 lenses are Pentax K-3 III Monochrome, Pentax KF and Pentax K-3 III.
Venus 105mm F2 is also available in Sony E , Canon EF, Nikon F (FX) and Sony Alpha mounts.
Venus 100mm F2.8 2X Ultra Macro is also available in Canon EF , Nikon F (FX) and Sony E 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 Venus 100mm F2.8 2X Ultra Macro is a prime lens with fixed focal lenght of 100mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 150mm.