Firstly: play around with the zoom. I have a much easier time with these at smaller sizes. Second, lean in close to your monitor, so that your eyes are straining a bit to keep the image in focus. Let your eyes "relax" out of focus. At first this might seem the same, but you're getting your eyes to effectively un-cross. Line up the three dots and you should now see the hemisphere in front of the plane, rather than as a cutout.