The Olympus Pen-F has a 20MP sensor, that’s four megapixels more than the previous E-P5. Does an extra four megapixels make a difference? Well just look at the dpreview.com studio scene comparison tool. The Pen-F definitely shows higher resolution compared to the older E-P5 with fewer megapixels.
However, when I tried to reproduce the experiment at home, I was not successful in seeing a difference. I think that once you have 16 megapixels of resolution, to get the benefits of more megapixels you have to be using the sharpest lenses, have perfect focus, absolutely no camera shake or shutter shock etc. Maybe my tripod wasn’t sturdy. Maybe the focus wasn’t exactly the same. I guess the people at dpreview.com are better at setting up these tests than I am.