Monitor ghosting test

What you are reading by eye: a dark smear trailing behind the block is the panel responding slowly, ghosting in the plain sense. A bright halo or reversed image in front of the block is inverse ghosting, overdrive compensation set too far. This test shows neither as a number: no response time is measured, and frame drops from a busy system can fake both, which is what the frame-rate readout is there to catch. Run it on the background you will actually work on; trails show best on dark backgrounds, halos on light ones.