I took this image to test 2 things. My manual focusing skills and to see how bad bokeh is with this lens. It was taken wide open at f3.5 and is sharp enough for my purposes. Bokeh is another matter, being a little bussier than the Olympus 135mm lens but can, in certain situations, be very good indeed. I find this little problem to be a Pentax characteristc with the manual focus lenses. The faster Pentex lenses may be different but my faster Pentax lens to-date is f2.8.