You are probably getting soft images from your OMD because of f11 or f1.8. The individual pixels are so small for a 16 mpix M43 camera that you get diffraction very soon, my guess probably anythingsmaller than about f5.6 will start to get softer. This is why one of the FF cameras like a 5D or a D700 will work better. You can stop down when you need lots of depth of field and to make your lenses sharper than you can with one of the small sensored cameras. Wide open most lenses will be a bit softer.
Your main problem looks like it is the camera not acquiring proper focus though