Unfortunately atrocious poor quality of optics. In direct comparison to the Panasonic Lumix 14-140 Olympus Super Zoom cuts regarding sharpness and contrast behavior is miserable. At 14mm bad in the center and in particular at the edge, between 25 and 45mm reasonably acceptable (at dimming at least one level), above 45mm continuously worse becoming and from 100mm no longer be used (neither center nor the screen). I have returned the lens and then tried three more copies at a well-stocked photo dealer - two slightly better one even worse. According to the statement of the photo dealer is aware of this issue of the massive fluctuating quality. There are obviously a few good specimens and a variety worse lenses that often suffer, inter alia, on decentralization. For me the issue is completed, this appearance is not my E-PL1, yet the Panasonic GH1 (where you yes Connection standard also fits). All tried out of my lenses (14-150) were worth the money not rudimentary, despite some concessions to a superzoom. The alternative, the Panasonic Lumix Vario 14-140 plays in a completely different performance class and is working on both the PENs as well as the Lumix cameras (G-series) properly with consistently good to very good results.
