The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Pentax FA 31mm F1.8 L and the Nikon 50mm f1.4G 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. Pentax FA 31mm F1.8 L is the longer of the two lenses at 69mm. The Nikon 50mm f1.4G with a length of 54mm, is 15mm shorter. On the other hand, the Nikon 50mm f1.4G has a larger diameter of 74mm compared to the Pentax FA 31mm F1.8 L's 65mm 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. Nikon 50mm f1.4G weighs 290g, 15% (55g) lighter than the Pentax FA 31mm F1.8 L's weight of 345g.
Filter Threads
Both the Pentax FA 31mm F1.8 L and the Nikon 50mm f1.4G have the same Filter thread size of 58mm.
Below are links to the 58mm filters that we recommend you to consider for these lenses:
Lens Mounts
The Pentax FA 31mm F1.8 L has the Pentax KAF lens mount whereas the Nikon 50mm f1.4G has the Nikon F (FX) lens mount. Some of the latest released cameras that are compatible with these mounts are Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF Mount and Nikon D6, Nikon D780 and Nikon D3500 for the Nikon F (FX) Mount.
Focal Range
Pentax FA 31mm F1.8 L is a prime lens with fixed focal lenght of 31mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
46.5mm.
On the other hand, the Nikon 50mm f1.4G 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.
