The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Samyang 100mm F2.8 Macro and the Pentax D-FA 50mm F2.8 Macro 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 100mm F2.8 Macro is the longer of the two lenses at 123mm. The Pentax D-FA 50mm F2.8 Macro with a length of 60mm, is 63mm shorter. Besides being longer, the Samyang 100mm F2.8 Macro also has a larger diameter of 73mm compared to the Pentax D-FA 50mm F2.8 Macro's 68mm 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 D-FA 50mm F2.8 Macro weighs 265g, 63% (455g) lighter than the Samyang 100mm F2.8 Macro's weight of 720g.
Filter Threads
The Samyang 100mm F2.8 Macro has a filter size of 67mm whereas the Pentax D-FA 50mm F2.8 Macro 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 67mm filters that we recommend you to consider for the Samyang 100mm F2.8 Macro:
And these are the 49mm filters that we recommend for the Pentax D-FA 50mm F2.8 Macro:
Lens Mounts
The Samyang 100mm F2.8 Macro has the Fujifilm X lens mount whereas the Pentax D-FA 50mm F2.8 Macro has the Pentax KAF lens mount. Some of the latest released cameras that are compatible with these mounts are Fujifilm X-T30 III, Fujifilm X-E5 and Fujifilm X-M5 for the Fujifilm X Mount and Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF Mount.
Samyang 100mm F2.8 Macro is also available in the Canon EF , Micro Four Thirds, Nikon F (FX), Pentax KAF, Samsung NX, Sony Alpha and Sony E mounts.
Focal Range
Samyang 100mm F2.8 Macro is a prime lens with fixed focal lenght of 100mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
150mm.
On the other hand, the Pentax D-FA 50mm F2.8 Macro 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.
