What causes monitor ghosting?
Monitor ghosting occurs when display pixels cannot transition between colors fast enough to match fast-moving graphics. This speed is measured in response time, typically Grey-to-Grey (GtG).
When response times are slow, pixels from the previous frame remain visible for a fraction of a second. This leaves a faint trail or trail-like smear behind moving objects. In display testing, this is a critical quality metric for gaming monitors.
Running a regular ghosting test helps you identify these artifacts. A monitor ghost test shows the severity of the trailing effect visually. While a high refresh rate (like 144Hz or 240Hz) helps, it cannot solve ghosting if the panel's pixel response is sluggish.
Evaluating your UFO test result
This interactive tool provides an instant, easy-to-use browser test. It uses highly precise animations to check response times directly in your web browser. No software installation is required.
For professional evaluations, reviewers use a pursuit camera setup. A camera moves along a rail at the exact speed of the on-screen graphics. This method matches human eye tracking to record true motion clarity.
Gamers and enthusiasts use these results to fine-tune their overdrive settings. Overdrive speeds up pixel transitions to eliminate blur. However, setting overdrive too high causes pixel overshoot, creating bright halo outlines behind moving objects.
Panel technology and ghosting performance
A monitor's tendency to ghost is heavily dependent on its panel type. Traditional LCD screens rely on physical rotation of liquid crystals to pass or block light, which naturally takes time. The speed of these crystal rotations determines the panel's gray-to-gray (GtG) response time.
For more detail, read our guide to monitor panel types. Here is a comparison of typical panel performances:
| Panel Type | Typical GtG Response | Ghosting Severity | Notes & Key Characteristics |
|---|---|---|---|
| OLED | < 0.1 ms | None | Near-instantaneous pixel transitions. Practically zero motion blur or trailing. |
| TN (Twisted Nematic) | 0.5 ms to 1 ms | Very Low | Historically the fastest LCD panel, but suffers from poor viewing angles and color accuracy. |
| IPS (In-Plane Switching) | 1 ms to 4 ms | Low to Moderate | Excellent colors and viewing angles. Modern IPS panels have very good response times. |
| VA (Vertical Alignment) | 4 ms to 10 ms | High (Dark Smearing) | Superb contrast ratios, but notoriously slow transitions from black to dark gray, causing "dark smearing." |
How to fix monitor ghosting
If your display fails a visual ghosting test, there are several troubleshooting steps you can take to reduce smearing and motion blur:
- Adjust display overdrive: Open your monitor's physical settings menu (OSD). Locate settings labeled overdrive, response time, or response time acceleration. Increase this level to speed up pixel transitions while avoiding settings that cause bright overshoot halos.
- Increase System Refresh Rate: Make sure your graphics card is sending the correct refresh rate to your screen. Go to your operating system's display settings and set it to the maximum supported frequency (e.g., 144Hz, 240Hz, or 360Hz). See our refresh rate guide or test your reaction time to check latency.
- Enable Motion Blur Reduction: Many monitors support backlight strobing (such as ELMB, ULMB, or DyAc). This inserts a brief black frame between screen refreshes, drastically improving perceived motion clarity.
- Use High-Quality Cables: Connect your display using a certified DisplayPort or high-speed HDMI cable. Low-quality cables can limit the maximum refresh rates or bandwidth available.
Best practices for motion clarity
- Run a ghost test at multiple speeds (such as 240px/s, 960px/s, and 1440px/s) to check performance across different gaming scenarios.
- Tune the overdrive setting step-by-step while watching the moving UFOs to find the best balance between trailing and overshoot halos.
- Perform a baseline browser test in a clean browser window with hardware acceleration enabled for the most accurate refresh rate mapping.