I noticed that this video has a very beautiful DOF, almost spot on. It is a video but should still be applicable to photography. So how is such precise and large Depth of field achieved? What kind of lend can be used on an SLR?
I have to agree with others that the DOF is not very large on the video. Understand that the longer the telephoto focal length is, the shorter the DOF will be. A large lens opening will also reduce DOF. sot to increase DOF use a lens that tends toward normal or wide angle and a small (large number like f16) F stop. If using a telephoto lens so you don't have to get close, you may be able to use motion tracking focus to keep the subject in focus.