In Image three I have adjusted the focus to 5m but kept the aperture at 5.6. The DOF has now changed, encompassing everything from 2.5m up to near the infinity symbol 8. As you can see from this example, when it is compared to image 2, if the point that I am focussing on is farther away, then the DOF will be greater at any given aperture, in this case f5.6.