How the ghosting test works
Each shape jumps a little further across the screen on every refresh. Pixels need a few milliseconds to change from one shade to another; if they're too slow, the shape leaves a faint copy of itself behind, called ghosting. Some screens overcorrect and leave a bright or dark halo instead, called overshoot or inverse ghosting. Testing on dark, mid and light backgrounds matters because panels are often slower at some transitions than others; slow dark-to-grey changes are common on VA panels.
On a high refresh rate screen the shapes look sharper because each step is smaller. Check yours on the refresh rate test.
Reducing ghosting
- Raise the refresh rate to the maximum your screen supports, in your display settings.
- Try the overdrive setting in the monitor's menu (often called response time or trace free). Pick the level with the least trailing and no halos.
- Turn off motion smoothing on TVs, or use Game mode, which usually gives the clearest motion.
Frequently asked questions
The shapes stutter instead of moving smoothly.
Close other tabs and apps, and check your refresh rate. Stutter is usually the computer missing frames, not ghosting.
Why is there no setting faster than 1440 px/s?
Faster than that, shapes cross a phone or laptop screen in a fraction of a second, which is too quick to follow.