The technical details behind this lens
The 12-40mm PRO is the first lens from Olympus with a constant f/2.8 aperture throughout its entire focal range. Its robust metal construction is splash, dust and freezeproof making it an excellent companion to the OM-D E-M1.
Versatile Use
A wide-to-portrait length lens with an equivalent of 24-80mm on a Micro Four Thirds mirrorless camera, it is an asset in any kit, wide enough for capturing landscapes and shooting in city laneways, but also with sufficient zoom to photograph intimate portraits. Zuiko Extra-low Reflection Optical (ZERO) lens coating also minimises lens flare and ghosting in strong lighting conditions.
Fast Lens and Fast Autofocus
A constant f/2.8 maximum aperture throughout the zoom range enhances both low-light and high-shutter-speed photography, while the bokeh is smooth from the round seven-blade diaphragm. Additionally, the Movie and Still Compatible (MSC) autofocus system is fast, smooth and reliable, and can instantly switches with a manual focus clutch.