DSLR Live View showing wrong f-stop

Using version 3.6 on a Mac running OS 10.10.1 cabled to a Canon 5D-II, with a 50 mm 1.8 lens.
The live view shows a different f-stop than is actually being used for image capture.
In other words, if the camera is set to an f-stop of 8.0, producing an image with minimal DOF, the live view shows substantial DOF (blurring of foreground and background), as though the f-stop was set to 1.8 or so.
Is there a way to get Live View to show an image better representing the final capture?

That is due to how a DSLR commonly works. For composition and focussing, the camera normally switches to the widest aperture (as it would if you looked through the viewfinder). Pressing the Depth Preview Button should show you the actual aperture. There might even be a setting in the 5D MkII that takes care of that permanently