The type of photography that you are planning to use is an important decision factor. Here we have evaluated the OM System 12-40mm F2.8 PRO II and the Pentax D FA 24-70mm F2.8 ED SDM 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 D FA 24-70mm F2.8 ED SDM WR is the longer of the two lenses at 110mm. The OM System 12-40mm F2.8 PRO II with a length of 84mm, is 26mm shorter. Besides being longer, the Pentax D FA 24-70mm F2.8 ED SDM WR also has a larger diameter of 89mm compared to the OM System 12-40mm F2.8 PRO II's 70mm diameter.
Below you can find a scaled side-by-side image of OM System 12-40mm F2.8 PRO II and Pentax D FA 24-70mm F2.8 ED SDM WR to get a better idea of how their sizes compare in real life.
Comparison image of the OM System 12-40mm F2.8 PRO II and the Pentax D FA 24-70mm F2.8 ED SDM WR Size and Weight 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. OM System 12-40mm F2.8 PRO II weighs 382g, which means it is 405g (51%) lighter than the Pentax D FA 24-70mm F2.8 ED SDM WR which has a weight of 787g.
Lens Mounts
The OM System 12-40mm F2.8 PRO II has the Micro Four Thirds lens mount whereas the Pentax D FA 24-70mm F2.8 ED SDM WR has the Pentax KAF3 lens mount . Some of the latest released cameras that are compatible with these mounts are OM System OM-3 Astro , OM System OM-5 II and OM System OM-3 for the Micro Four Thirds Mount and Pentax K-3 III Mono , Pentax KF and Pentax K-3 III for the Pentax KAF3 Mount.
Focal Range
OM System 12-40mm F2.8 PRO II has a focal range of 12-40mm and
3.3X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of
24-80mm when used on a FourThirds format camera.
On the other hand, the Pentax D FA 24-70mm F2.8 ED SDM WR has a focal range of 24-70mm and 2.9X zoom ratio . When it is mounted on an APS-C sensor camera with 1.5x crop, it provides a 35mm (FF) equivalent of 36 - 105mm .
