The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Viltrox AF 20mm f2.8 Z and the Pentax FA 50mm F1.4 Classic 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. Viltrox AF 20mm f2.8 Z is the longer of the two lenses at 60mm. The Pentax FA 50mm F1.4 Classic with a length of 37mm, is 23mm shorter. On the other hand, there is no difference between the max diameters of these lenses, both coming at 65mm.
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 AF 20mm f2.8 Z weighs 157g, which means it is 59g (27%) lighter than the Pentax FA 50mm F1.4 Classic which has a weight of 216g.
Filter Threads
The Viltrox AF 20mm f2.8 Z has a filter size of 52mm whereas the Pentax FA 50mm F1.4 Classic has a 49mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 52mm filters that we recommend you to consider for the Viltrox AF 20mm f2.8 Z:
And these are the 49mm filters that we recommend for the Pentax FA 50mm F1.4 Classic:
Lens Mounts
The Viltrox AF 20mm f2.8 Z has the Nikon Z lens mount whereas the Pentax FA 50mm F1.4 Classic has the Pentax KAF lens mount. Some of the latest released cameras that are compatible with these mounts are Nikon ZR, Nikon Z5 II and RED Komodo-X 6K Z for the Nikon Z Mount and Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF Mount.
Focal Range
Viltrox AF 20mm f2.8 Z is a prime lens with fixed focal lenght of 20mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
30mm.
On the other hand, the Pentax FA 50mm F1.4 Classic is a prime lens with fixed focal lenght of 50mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 75mm.
