Run a controlled moving high-contrast target at repeatable speeds and backgrounds. Use it to visually compare dark trails, smearing, bright inverse-ghosting halos and motion clarity before and after changing monitor overdrive or refresh settings.
Conventional ghosting can appear as a darker or colored trail when transitions do not settle before the target moves on. Aggressive overdrive can overshoot and create a bright or inverted halo.
LCD response behavior can change with the starting and ending luminance values. A mode that looks clean on a dark background can show different trailing or overshoot on gray or light transitions.
Higher target speeds make trails easier to see but also increase distance traveled per displayed frame. The live cadence readout estimates this page's current animation rate so obvious browser/system throttling is visible during comparisons.
Use the separate refresh-rate test for a longer timing sample.
At one fixed speed and refresh mode, compare Off → Normal → Fast (or equivalent settings). A useful setting reduces visible trailing without introducing a strong bright inverse halo. The most aggressive setting is not always the cleanest.
No. That requires controlled measurement equipment and a defined transition methodology.
That can be consistent with overdrive overshoot. Compare the next-lower setting at the same speed and refresh rate.
You can for personal comparisons, but phone shutter, exposure and rolling shutter add their own artifacts.
Motion is hidden and paused by default. Pressing START is treated as an intentional override specifically for this diagnostic.