The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Venus 100mm F2.8 2X Ultra Macro and the Pentax-D FA 85mm F1.4 ED SDM AW 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 Pentax-D FA 85mm F1.4 ED SDM AW with a length of 124mm, is 1mm shorter. On the other hand, the Pentax-D FA 85mm F1.4 ED SDM AW has a larger diameter of 95mm 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 100mm F2.8 2X Ultra Macro and Pentax-D FA 85mm F1.4 ED SDM AW 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, which means it is 617g (49%) lighter than the Pentax-D FA 85mm F1.4 ED SDM AW which has a weight of 1255g.
Filter Threads
The Venus 100mm F2.8 2X Ultra Macro has a filter size of 67mm whereas the Pentax-D FA 85mm F1.4 ED SDM AW has a 82mm 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 100mm F2.8 2X Ultra Macro:
And these are the 82mm filters that we recommend for the Pentax-D FA 85mm F1.4 ED SDM AW:
Lens Mounts
The Venus 100mm F2.8 2X Ultra Macro has the Pentax KAF2 lens mount whereas the Pentax-D FA 85mm F1.4 ED SDM AW has the Pentax KAF4 lens mount. Some of the latest released cameras that are compatible with these mounts are Pentax K-3 III Monochrome, Pentax KF and Pentax K-3 III for the Pentax KAF2 Mount and , and for the Pentax KAF4 Mount.
Venus 100mm F2.8 2X Ultra Macro is also available in Canon EF , Nikon F (FX) and Sony E mounts.
Focal Range
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.
On the other hand, the Pentax-D FA 85mm F1.4 ED SDM AW 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.