Olympus 50mm f/1.8 OM F.Zuiko plus PEN E-P1 Test – SLRGear reviews this combination and provides two full-resolution test photos.
The article notes that you’ll need to use the Olympus MF-2 OM Lens to Micro Four Thirds Adapter in order to mount the Zuiko OM 50/1.8 on to the EP-1.