The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Pentax FA 50mm F1.4 Classic and the Pentax FA 43mm F1.9 L 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 50mm F1.4 Classic is the longer of the two lenses at 37mm. The Pentax FA 43mm F1.9 L with a length of 27mm, is 10mm shorter. Besides being longer, the Pentax FA 50mm F1.4 Classic also has a larger diameter of 65mm compared to the Pentax FA 43mm F1.9 L's 64mm 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. Pentax FA 43mm F1.9 L weighs 155g, 28% (61g) lighter than the Pentax FA 50mm F1.4 Classic's weight of 216g.
Below you can find the dimension and weight table of the Standard Prime Lenses in Pentax KAF Mount for size comparison purposes.
Standard Lenses in Pentax KAF Mount for Size Comparison
Filter Threads
Both the Pentax FA 50mm F1.4 Classic and the Pentax FA 43mm F1.9 L have the same Filter thread size of 49mm.
Below are links to the 49mm filters that we recommend you to consider for these lenses:
Lens Mounts
Both the Pentax FA 50mm F1.4 Classic and the Pentax FA 43mm F1.9 L 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 Mono, Pentax KF and Pentax K-3 III.
Focal Range
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.
On the other hand, the Pentax FA 43mm F1.9 L is a prime lens with fixed focal lenght of 43mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 64.5mm.
