The type of photography that you are planning to use is an important decision factor. Here we have evaluated the Pentax 16-50mm F2.8 ED PLM AW and the PENTAX28-105mm F3.5-5.6 WR 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 16-50mm F2.8 ED PLM AW is the longer of the two lenses at 117mm. The PENTAX28-105mm F3.5-5.6 WR with a length of 87mm, is 30mm shorter. Besides being longer, the Pentax 16-50mm F2.8 ED PLM AW also has a larger diameter of 84mm compared to the PENTAX28-105mm F3.5-5.6 WR's 73mm 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. PENTAX28-105mm F3.5-5.6 WR weighs 440g, 38% (272g) lighter than the Pentax 16-50mm F2.8 ED PLM AW's weight of 712g.
Filter Threads
The Pentax 16-50mm F2.8 ED PLM AW has a filter size of 77mm whereas the PENTAX28-105mm F3.5-5.6 WR has a 62mm diameter. Larger filters are generally more expensive than the smaller ones given all the other features are equal.
Below are links to the 77mm filters that we recommend you to consider for the Pentax 16-50mm F2.8 ED PLM AW:
And these are the 62mm filters that we recommend for the PENTAX28-105mm F3.5-5.6 WR:
Lens Mounts
The Pentax 16-50mm F2.8 ED PLM AW has the Pentax KAF4 lens mount whereas the PENTAX28-105mm F3.5-5.6 WR has the Pentax KAF3 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 KAF4 Mount and Pentax K-3 III Mono, Pentax KF and Pentax K-3 III for the Pentax KAF3 Mount.
Focal Range
Pentax 16-50mm F2.8 ED PLM AW has a focal range of 16-50mm and
3.1X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
24-75mm when used on a APS-C / DX format camera.
On the other hand, the 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.
