The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Samyang AF 75mm F1.8 FE and the Pentax FA 77mm 1.8 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. Samyang AF 75mm F1.8 FE is the longer of the two lenses at 69mm. The Pentax FA 77mm 1.8 L with a length of 48mm, is 21mm shorter. Besides being longer, the Samyang AF 75mm F1.8 FE also has a larger diameter of 65mm compared to the Pentax FA 77mm 1.8 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. Samyang AF 75mm F1.8 FE weighs 230g, which means it is 40g (14%) lighter than the Pentax FA 77mm 1.8 L which has a weight of 270g.
Filter Threads
The Samyang AF 75mm F1.8 FE has a filter size of 58mm whereas the Pentax FA 77mm 1.8 L 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 58mm filters that we recommend you to consider for the Samyang AF 75mm F1.8 FE:
And these are the 49mm filters that we recommend for the Pentax FA 77mm 1.8 L:
Lens Mounts
The Samyang AF 75mm F1.8 FE has the Sony E lens mount whereas the Pentax FA 77mm 1.8 L has the Pentax KAF lens mount. Some of the latest released cameras that are compatible with these mounts are Sony A9 III, Sony A7C Mark II and Sony A7CR for the Sony E Mount and Pentax K-3 III Monochrome, Pentax KF and Pentax K-3 III for the Pentax KAF Mount.
Focal Range
Samyang AF 75mm F1.8 FE is a prime lens with fixed focal lenght of 75mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
112.5mm.
On the other hand, the Pentax FA 77mm 1.8 L is a prime lens with fixed focal lenght of 77mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 115.5mm.