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 Panasonic 7-14mm F4 ASPH 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. OM System 12-40mm F2.8 PRO II is the longer of the two lenses at 84mm. The Panasonic 7-14mm F4 ASPH with a length of 83mm, is 1mm shorter. On the other hand, there is no difference between the max diameters of these lenses, both coming at 70mm.
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. Panasonic 7-14mm F4 ASPH weighs 300g, 21% (82g) lighter than the OM System 12-40mm F2.8 PRO II's weight of 382g.
Lens Mounts
Both the OM System 12-40mm F2.8 PRO II and the Panasonic 7-14mm F4 ASPH has the same Micro Four Thirds lens mount. Some of the latest released cameras that are compatible with the Micro Four Thirds lenses are OM System OM-3 Astro, OM System OM-5 II and OM System OM-3.
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 Panasonic 7-14mm F4 ASPH has a focal range of 7-14mm and 2.0X zoom ratio which has an effective (full-frame 35mm equivalent) focal range of 14-28mm when used on a FourThirds format camera.