The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Zeiss Otus 100mm F1.4 and the Carl Zeiss Planar T1,4/85 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 Carl Zeiss Planar T1,4/85 with a length of 85mm, is 44mm shorter. Besides being longer, the Zeiss Otus 100mm F1.4 also has a larger diameter of 101mm compared to the Carl Zeiss Planar T1,4/85's 78mm 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. Carl Zeiss Planar T1,4/85 weighs 700g, 50% (705g) lighter than the Zeiss Otus 100mm F1.4's weight of 1405g.
Below you can find the dimension and weight table of the Telephoto Prime Lenses in Canon EF Mount for size comparison purposes.
Telephoto Lenses in Canon EF Mount for Size Comparison
Filter Threads
The Zeiss Otus 100mm F1.4 has a filter size of 86mm whereas the Carl Zeiss Planar T1,4/85 has a 72mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 86mm filters that we recommend you to consider for the Zeiss Otus 100mm F1.4:
And these are the 72mm filters that we recommend for the Carl Zeiss Planar T1,4/85:
Lens Mounts
Both the Zeiss Otus 100mm F1.4 and the Carl Zeiss Planar T1,4/85 has the same Canon EF lens mount. Some of the latest released cameras that are compatible with the Canon EF lenses are Canon 1D X III, Canon 6D MII and Canon 5D MIV.
Zeiss Otus 100mm F1.4 is also available in Nikon F (FX) mount.
Carl Zeiss Planar T1,4/85 is also available in Pentax KAF and Nikon F (FX) mounts.
Focal Range
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 1.6x crop, it provides a 35mm (FF) equivalent of
160mm.
On the other hand, the Carl Zeiss Planar T1,4/85 is a prime lens with fixed focal lenght of 85mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 136mm.