The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Sigma 105mm F2.8 EX DG Macro and the Rokinon 85mm 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. Sigma 105mm F2.8 EX DG Macro is the longer of the two lenses at 98mm. The Rokinon 85mm F1.4 with a length of 75mm, is 23mm shorter. On the other hand, the Rokinon 85mm F1.4 has a larger diameter of 78mm compared to the Sigma 105mm F2.8 EX DG Macro's 74mm 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. Sigma 105mm F2.8 EX DG Macro weighs 460g, which means it is 79g (14%) lighter than the Rokinon 85mm F1.4 which has a weight of 539g.
Filter Threads
The Sigma 105mm F2.8 EX DG Macro has a filter size of 62mm whereas the Rokinon 85mm F1.4 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 62mm filters that we recommend you to consider for the Sigma 105mm F2.8 EX DG Macro:
And these are the 72mm filters that we recommend for the Rokinon 85mm F1.4:
Lens Mounts
Both the Sigma 105mm F2.8 EX DG Macro and the Rokinon 85mm F1.4 has the same Pentax KAF lens mount. Some of the latest released cameras that are compatible with the Pentax KAF lenses are Pentax K-3 III Monochrome, Pentax KF and Pentax K-3 III.
Sigma 105mm F2.8 EX DG Macro is also available in Canon EF , Nikon F (FX), Sony Alpha, Sigma SA and Four Thirds mounts.
Rokinon 85mm F1.4 is also available in Canon EF , Four Thirds, Sony Alpha, Samsung NX and Nikon F (FX) mounts.
Focal Range
Sigma 105mm F2.8 EX DG Macro is a prime lens with fixed focal lenght of 105mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
157.5mm.
On the other hand, the Rokinon 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.