The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Pentax-D FA 85mm F1.4 ED SDM AW and the Zeiss Otus 100mm F1.4 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. Zeiss Otus 100mm F1.4 is the longer of the two lenses at 129mm. The Pentax-D FA 85mm F1.4 ED SDM AW with a length of 124mm, is 5mm shorter. Besides being longer, the Zeiss Otus 100mm F1.4 also has a larger diameter of 101mm compared to the Pentax-D FA 85mm F1.4 ED SDM AW's 95mm 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-D FA 85mm F1.4 ED SDM AW weighs 1255g, which means it is 150g (10%) lighter than the Zeiss Otus 100mm F1.4 which has a weight of 1405g.
Filter Threads
The Pentax-D FA 85mm F1.4 ED SDM AW has a filter size of 82mm whereas the Zeiss Otus 100mm F1.4 has a 86mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 82mm filters that we recommend you to consider for the Pentax-D FA 85mm F1.4 ED SDM AW:
And these are the 86mm filters that we recommend for the Zeiss Otus 100mm F1.4:
Lens Mounts
The Pentax-D FA 85mm F1.4 ED SDM AW has the Pentax KAF4 lens mount whereas the Zeiss Otus 100mm F1.4 has the Nikon F (FX) lens mount. Some of the latest released cameras that are compatible with these mounts are , and for the Pentax KAF4 Mount and Nikon D6, Nikon D780 and Nikon D3500 for the Nikon F (FX) Mount.
Zeiss Otus 100mm F1.4 is also available in Canon EF mount.
Focal Range
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.
On the other hand, the Zeiss Otus 100mm F1.4 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.