The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Zeiss Otus 85mm f1.4 and the Canon RF 135mm F1.8 L IS USM 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. Canon RF 135mm F1.8 L IS USM is the longer of the two lenses at 130mm. The Zeiss Otus 85mm f1.4 with a length of 128mm, is 2mm shorter. Besides being longer, the Canon RF 135mm F1.8 L IS USM also has a larger diameter of 89mm compared to the Zeiss Otus 85mm f1.4's 88mm 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. Canon RF 135mm F1.8 L IS USM weighs 935g, 10% (105g) lighter than the Zeiss Otus 85mm f1.4's weight of 1040g.
Below you can find the dimension and weight table of the Telephoto Prime Lenses in Canon RF Mount for size comparison purposes.
Telephoto Lenses in Canon RF Mount for Size Comparison
Filter Threads
The Zeiss Otus 85mm f1.4 has a filter size of 77mm whereas the Canon RF 135mm F1.8 L IS USM 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 77mm filters that we recommend you to consider for the Zeiss Otus 85mm f1.4:
And these are the 82mm filters that we recommend for the Canon RF 135mm F1.8 L IS USM:
Lens Mounts
Both the Zeiss Otus 85mm f1.4 and the Canon RF 135mm F1.8 L IS USM has the same Canon RF lens mount. Some of the latest released cameras that are compatible with the Canon RF lenses are Canon R6 V, Canon R6 III and Canon C50.
Zeiss Otus 85mm f1.4 is also available in the Canon EF , Nikon F (FX), Sony E and Nikon Z mounts.
Focal Range
Zeiss Otus 85mm f1.4 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 Canon RF 135mm F1.8 L IS USM is a prime lens with fixed focal lenght of 135mm. When it is mounted on an APS-C sensor camera with 1.6x crop, it provides a 35mm (FF) equivalent of 216mm.
