Monitor ghosting is a common issue that many gamers and video users encounter in daily use: when images move quickly, object edges appear blurry, smeared, or trailed; text briefly becomes blurry when scrolling web pages; and scene details become unclear when turning around in FPS games. Many people's first reaction is that the monitor's "response time is not enough," but in reality, the causes of ghosting involve multiple aspects including panel type, Overdrive settings, refresh rate, and usage environment.

This article will systematically analyze the causes of monitor ghosting, compare the differences in response time and ghosting performance among the three mainstream panel types—TN, IPS, and VA—and focus on explaining how Overdrive settings affect ghosting and smearing. Finally, it will introduce how to reduce ghosting through OSD adjustments and online test tools, giving you more confidence when purchasing and tuning a monitor.

1. The Essence of Ghosting: Response Time and Persistence of Vision

LCD monitors control the amount of light passing through by deflecting liquid crystal molecules, thereby displaying different gray levels. The time required for liquid crystal molecules to switch from one state to another is called response time. If the response time is too long, the previous frame has not fully disappeared before the next frame begins to display, and the human eye will see afterimages or trailing—this is the direct source of ghosting.

  • GTG (Gray-to-Gray): The most common specification, representing the time required for liquid crystal molecules to switch between typical gray levels. A low GTG does not mean all scenarios are fast; transitions from dark to bright can be significantly slower.
  • MPRT (Moving Picture Response Time): Simulates motion clarity by inserting black frames, which is closer to actual viewing experience but reduces brightness. A low MPRT typically means less ghosting.
  • Persistence of Vision: The human eye briefly retains light signals. Even if the panel response is zero, continuous frame transitions still produce a certain amount of blur. This is a characteristic of human vision and can only be mitigated by increasing refresh rate or inserting black frames.

Therefore, simply looking at a 1ms GTG specification cannot fully determine ghosting performance; it also needs to be evaluated in combination with panel type and actual testing.

2. Three Main Panel Types and Ghosting Differences

  • TN Panels: The fastest response time, commonly used in early esports monitors, with GTG reaching 1ms or even lower. Ghosting is the least noticeable during fast-moving images, but color performance and viewing angles are poor, with obvious color shift when viewed from the side. Suitable for competitive players who prioritize ultimate response speed.
  • IPS Panels: Excellent color and viewing angles. IPS response time has improved significantly in recent years, with mainstream fast IPS panels achieving GTG of 1-4ms, offering a balanced overall performance. However, slight ghosting may still appear in some dark scenes, not as clean as top-tier TN panels.
  • VA Panels: High contrast ratio and good black performance, but liquid crystal molecules deflect more slowly, especially when switching from dark to bright, which is noticeably slower than IPS and TN. This easily causes black trailing (also known as "VA smear") when moving quickly against dark backgrounds. The ghosting issue of VA panels is more prominent on budget products and is not suitable for users sensitive to response speed.

If you are very sensitive to ghosting, you should prioritize TN or fast IPS panels when choosing a monitor; if you value contrast ratio and black performance for movie watching, VA panels require accepting a certain degree of ghosting.

3. How Overdrive Settings Affect Ghosting and Smearing

Overdrive is a technology in which the monitor's driver board increases the liquid crystal driving voltage to force liquid crystal molecules to deflect faster. An appropriate Overdrive level can significantly reduce ghosting, but improper settings can introduce new problems.

  • Principle: Under normal driving voltage, liquid crystal deflection is slow, and frame transitions take longer. Overdrive applies a higher voltage at the moment of gray-level transition, accelerating the liquid crystal to reach the target state faster, then drops back to the holding voltage, thereby reducing response time.
  • Level too low: Ghosting remains noticeable, response time improvement is insufficient, and edges of fast-moving objects appear blurry and fuzzy.
  • Level too high: Liquid crystal overshoots, the target gray level is exceeded, and the image shows reverse afterimages or bright trailing (also known as ghosting/overshoot). For example, a white object moving against a dark background may show a white halo or inverted-color trailing at the edges.
  • Recommended setting: Most monitors offer options such as "Off/Standard/Fast/Extreme," and it is generally recommended to choose a middle level, such as "Standard" or "Fast." Observe the balance between ghosting and smearing in the UFO test and find the highest level without obvious ghosting artifacts.

Overdrive is not always better when set higher; it needs to match the panel response time and refresh rate. Excessive Overdrive will produce overshoot artifacts that are more noticeable than ghosting itself, affecting the viewing experience.

4. How to Reduce Ghosting Through OSD Adjustments

  • Enable Overdrive: Enter the monitor's OSD menu, find the "Response Time" or "Overdrive" option, and test gradually from low to high. Office scenarios can use a lower level, while gaming scenarios should use a middle or higher level.
  • Adjust refresh rate: Ensure the system refresh rate is set to the highest value supported by the monitor. A high refresh rate reduces the duration of each frame, and combined with low response time, can significantly reduce ghosting.
  • Enable FreeSync/G-Sync: Variable refresh rate technology eliminates tearing and additional blur caused by frame rate fluctuations, making motion smoother and indirectly improving ghosting perception.
  • Enable black frame insertion: If the monitor offers features such as MPRT/ULMB/1ms MPRT, you can try enabling them, but they will reduce brightness and may introduce flicker; sensitive users should use with caution.
  • Adjust brightness and contrast: Ghosting is more noticeable in low-brightness scenes. Appropriately increasing brightness or using dark enhancement features can alleviate the black trailing issue of VA panels.

5. Online Ghosting Test Methods

To accurately determine the degree of ghosting and smearing, you can run the UFO ghosting test online:

  • UFO Test: Open testufo.com or a similar online tool and observe whether the edges of the fast-moving UFO graphic are clear and whether there is trailing or inverted-color ghosting.
  • Switch Overdrive: In the test screen, adjust the monitor's Overdrive level step by step to find the level with the clearest edges and no obvious overshoot ghosting.
  • Scrolling text test: Quickly scroll through web page text and observe whether the text is blurry or has black or bright edges. If white trailing appears at the edges of text, the Overdrive may be too high.
  • In-game testing: Turn quickly in an FPS game and observe whether object edges in the scene stick together or have double images. Fine-tune repeatedly in combination with the monitor's OSD settings.

6. Summary

Monitor ghosting is not caused by a single factor. The panel type determines the physical lower limit of response time, Overdrive settings determine the balance between actual response speed and overshoot ghosting, and refresh rate and synchronization technology affect the overall smoothness of motion. Before purchasing a monitor, you can choose a panel based on your use case: for competitive gaming, prioritize TN or fast IPS; for video entertainment, VA can be considered but a certain degree of ghosting must be accepted. When encountering ghosting during use, first adjust Overdrive and refresh rate, then verify with online tests—often significant improvement can be achieved without replacing hardware.