Designed specifically for the Four Thirds SLR system, the Olympus 14-54mm has a useful effective zoom range of 28-108mm.
Better still, as one of the 'pro' level lenses in the Zuiko Digital line-up, build quality feels consummately sturdy, and the lens features dust and moisture seals, including a rubber o-ring incorporated into the metal mounting plate. It's similar to the arrangement that Canon uses on most of its L-series (Luxury) lenses.
The Olympus isn't quite a constant-aperture lens, but the maximum aperture is a fast f/2.8 at the wide-angle end of the zoom range. This shrinks by only two thirds of a stop at the telephoto end. It makes it a good choice for low-light shooting or for when you want to minimise depth of field.
Olympus is well-known for its great lenses, but testing this one on a new E-5 body was a disappointment. Colour fringing was very noticeable and sharpness and contrast were poor throughout the entire zoom range, but vignetting and distortion were well contained.
Autofocus proved fairly quick and quiet, and a full-time manual override option is available via the camera's menu system.
The electronically linked focus ring is wonderfully precise, and an absolute joy to use. Even so, given the lens's below-average optical performance in our lab tests, we don't feel it does enough to justify its expensive price tag.
Lenses with pro aspirations need to be able to cope with inclement weather. This Olympus has a rubber sealing ring incorporated into the mounting plate to guard against the ingress of dust and moisture.
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