The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Viltrox 75mm f1.8 X and the Rokinon 85mm F1.8 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. Rokinon 85mm F1.8 is the longer of the two lenses at 81mm. The Viltrox 75mm f1.8 X with a length of 76mm, is 5mm shorter. On the other hand, the Viltrox 75mm f1.8 X has a larger diameter of 69mm compared to the Rokinon 85mm F1.8's 68mm 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. Viltrox 75mm f1.8 X weighs 335g, which means it is 9g (2%) lighter than the Rokinon 85mm F1.8 which has a weight of 344g.
Below you can find the dimension and weight table of the Telephoto Prime Lenses in Fujifilm X Mount for size comparison purposes.
Telephoto Lenses in Fujifilm X Mount for Size Comparison
Filter Threads
The Viltrox 75mm f1.8 X has a filter size of 58mm whereas the Rokinon 85mm F1.8 has a 62mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 58mm filters that we recommend you to consider for the Viltrox 75mm f1.8 X:
And these are the 62mm filters that we recommend for the Rokinon 85mm F1.8:
Lens Mounts
Both the Viltrox 75mm f1.8 X and the Rokinon 85mm F1.8 has the same Fujifilm X lens mount. Some of the latest released cameras that are compatible with the Fujifilm X lenses are Fujifilm X-T30 III, Fujifilm X-E5 and Fujifilm X-M5.
Rokinon 85mm F1.8 is also available in Canon EF-M and Sony E mounts.
Focal Range
Viltrox 75mm f1.8 X is a prime lens with fixed focal lenght of 75mm which has an effective (full-frame 35mm equivalent) focal range of
112.5mm when used on a APS-C / DX format camera.
On the other hand, the Rokinon 85mm F1.8 is a prime lens with fixed focal lenght of 85mm which has an effective (full-frame 35mm equivalent) focal range of 127.5mm when used on a APS-C / DX format camera.