Discussions on the Internet of shallow depth of field continue to amuse me. Most chat threads are centered almost exclusively on discussions of fast apertures and in particular why you should buy a faster lens. But the reality is if you want to create a shallow depth of field, it's easier to do so with a longer focal length than it is with a faster lens. If you want to see how this works, download an app called DOF Simulator and play around with it. You will quickly conclude that aperture is the least important component for creating a shallow depth of field and that focal length and distance to the subject are where a shallow depth of field is really created.