Test your display for ghosting, motion blur, trailing and pixel response issues with real-time motion patterns.
Start the test to begin the motion pattern. Look for visible trails or smearing behind moving objects.
Watch the trailing edge of the moving object — a fast panel shows a crisp edge; a slow panel drags a tail.This result describes your visual observation and browser rendering conditions. It is not a laboratory measurement of monitor response time.
Learn what screen ghosting is, how motion blur appears, how to test your display using moving patterns, and why browser-based tests cannot directly measure hardware response time.
Screen ghosting is an optical artifact where moving imagery leaves a faint duplicate or trailing silhouette behind it. It occurs primarily when subpixels take longer to transition between color shades than the frame duration of the monitor.
While motion blur softens the entire moving object due to eye tracking and frame hold persistence (MPRT), ghosting specifically manifests as a distinct shadow or trail dragging behind high-contrast edges due to slow liquid crystal response (GtG).
Liquid crystals in LCD displays physically reorient when electrical voltage changes. If a subpixel requires 15 milliseconds to rotate, but the display refreshes every 6.9 milliseconds (144Hz), the previous image lingers as a visible ghost trail.
Observe a high-contrast object moving horizontally at moderate velocity (480–960 px/s). Track the leading edge with your eyes and inspect the trailing edge: a clean monitor shows an immediate sharp transition to the background.
Higher refresh rates compress frame durations (16.67ms at 60Hz down to 4.17ms at 240Hz). This reduces sample-and-hold blur, but if liquid crystal response times lag behind the refresh interval, ghosting remains visible.
Fast pixel response times (1–3ms GtG) allow liquid crystals to complete their color changes before the next frame is presented, preventing pixel values from overlapping into trailing smears.
Monitor overdrive applies elevated electrical voltage surges to accelerate liquid crystal realignment. When properly tuned, overdrive virtually eliminates trailing; when set too aggressively, it produces inverse ghosting (bright halos).
If your frame rate drops below your refresh rate, frames repeat and stay on screen longer, increasing perceived blur. Matching frame rate to display refresh rate ensures the cleanest possible motion rendering.
Testing at 120 px/s examines fine edge transitions, while testing at 960 px/s and 1920 px/s stretches trailing across larger screen distances, making faint liquid crystal response delays immediately obvious.
Ensure your monitor has reached normal operating temperature, clean the screen surface, test in fullscreen mode, and compare different contrast modes (e.g. White on Black vs Cyan on Black).
A browser executes in a software sandbox and has no direct telemetry into the physical photon emissions or chemical state of your display panel. Laboratory testing requires specialized photodiode oscilloscopes or pursuit cameras.
Screen ghosting is a visual artifact where moving objects leave a faint trail, smear, or secondary silhouette behind them. It occurs when a monitor's physical liquid crystals cannot shift between colors as quickly as the frame updates.
Ghosting looks like a dark or discolored tail dragging directly behind moving high-contrast elements. In severe cases, it can produce a faint duplicate image or cause fast-moving characters and reticles in games to appear doubled.
No. Motion blur softens the entire moving object due to frame hold duration on your retina (MPRT). Ghosting specifically leaves trailing shadows behind high-contrast edges due to sluggish pixel transition response times (GtG).
Run a high-contrast moving pattern (like the UFO Motion test above) across a dark background. Track the object closely with your eyes and look behind the rear edge for trailing streaks or shadows.
Higher refresh rates reduce eye-tracking motion blur (persistence blur) because frames are displayed for less time (6.94ms vs 16.67ms). However, if the panel's physical liquid crystal response time is slow, ghosting will still remain visible.
240Hz dramatically reduces motion blur, but can actually make slow pixel response more noticeable if the pixels cannot finish transitioning within the 4.17ms frame window.
No. Browser JavaScript cannot access the physical optical emissions or electrical transitions of your monitor's panel. This tool provides deterministic motion patterns so you can evaluate ghosting with your own eyes.
Ghost trails are caused by slow Gray-to-Gray (GtG) transition speeds in the liquid crystals. When an object moves forward, old pixels take several milliseconds to transition back to the background color.
Yes. Monitor overdrive sends higher electrical voltage to twist liquid crystals more quickly, significantly reducing ghosting trails. However, excessive overdrive can cause inverse ghosting (bright halos).
You can often minimize ghosting by: 1) enabling or tuning your monitor's Overdrive setting, 2) running at your monitor's native refresh rate, 3) ensuring your room isn't excessively cold (cold liquid crystals transition slower), and 4) avoiding extreme contrast configurations.
At low speeds (e.g. 120 px/s), pixel transitions happen over fewer screen pixels, making trails short. At high speeds (960–1920 px/s), trailing stretches across a wider physical pixel area, making it easier to spot.
Modern Fast-IPS displays have very low ghosting when overdrive is calibrated. Older or budget IPS panels may show minor trailing in high-speed motion.
VA (Vertical Alignment) monitors often exhibit dark-level smearing, where transitions between pure black and dark grays are significantly slower (up to 30ms), leaving distinct dark streaks behind moving objects.
OLED pixels transition almost instantaneously (<0.1ms GtG), virtually eliminating ghosting. Any perceived softness on OLED is due to sample-and-hold persistence blur, not liquid crystal ghosting.
VSync locks the browser render rate to your monitor's refresh cycle, preventing screen tearing and ensuring perfectly even frame pacing for consistent visual inspection.
Run a controlled motion test and visually inspect your screen for ghosting, trailing and motion blur.
