The type of photography that you are planning to use is an important decision factor. Here we have evaluated the PENTAX28-105mm F3.5-5.6 WR and the Samyang 24mm f1.4 for their suitability to various photography scenarios:
Size and Weight Comparison
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. PENTAX28-105mm F3.5-5.6 WR weighs 440g, which means it is 140g (24%) lighter than the Samyang 24mm f1.4 which has a weight of 580g.
Filter Threads
The PENTAX28-105mm F3.5-5.6 WR has a filter size of 62mm whereas the Samyang 24mm f1.4 has a 77mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 62mm filters that we recommend you to consider for the PENTAX28-105mm F3.5-5.6 WR:
And these are the 77mm filters that we recommend for the Samyang 24mm f1.4:
Lens Mounts
The PENTAX28-105mm F3.5-5.6 WR has the Pentax KAF3 lens mount whereas the Samyang 24mm f1.4 has the Pentax KAF lens mount. Some of the latest released cameras that are compatible with these mounts are Pentax K-3 III Monochrome, Pentax KF and Pentax K-3 III for the Pentax KAF3 Mount and Pentax K-3 III Monochrome, Pentax KF and Pentax K-3 III for the Pentax KAF Mount.
Samyang 24mm f1.4 is also available in Canon EF , Nikon F (FX), Four Thirds, Sony Alpha, Sony E and Samsung NX mounts.
Focal Range
PENTAX28-105mm F3.5-5.6 WR has a focal range of 28-105mm and
3.8X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of
42 - 157.5mm.
On the other hand, the Samyang 24mm f1.4 is a prime lens with fixed focal lenght of 24mm. When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 36mm.