What is Ghosting?
Ghosting is a visual artifact on displays where a faint, blurry trail or shadow appears behind moving objects. If you have ever noticed that a fast-moving character in a game seems to leave a translucent afterimage, or that scrolling text appears smeared, you have seen ghosting. The phenomenon occurs because the display’s pixels cannot change color fast enough to keep up with the motion on screen – the old image lingers while the new one is already being drawn. Ghosting is most noticeable in fast-paced gaming, sports broadcasts, and any content with rapid on-screen movement. While no LCD display is completely immune, some panel types, response times, and monitor settings can dramatically reduce or virtually eliminate the problem.
In-Depth
Why Ghosting Happens
At a fundamental level, ghosting is a response time problem. Every pixel on an LCD panel changes color by physically reorienting liquid crystal molecules – and that physical movement takes time. Response time measures how long a pixel takes to transition from one color to another (typically measured as gray-to-gray, or GtG). When response time is slow, the previous frame’s image has not fully faded before the next frame appears, creating a visible overlap that your eyes perceive as a ghost or smear.
The severity of ghosting depends on three factors:
- Pixel response time – Slower response = more ghosting
- Speed of on-screen motion – Faster movement makes ghosting more visible
- Refresh rate – Higher refresh rates show each frame for less time, which can either help or expose response time limitations
Panel Types and Ghosting
Different panel technologies have inherently different response characteristics:
| Panel Type | Typical GtG Response | Ghosting Tendency | Strengths |
|---|---|---|---|
| TN | 1-2 ms | Low | Fastest LCD response times |
| IPS | 3-5 ms (fast IPS: 1 ms) | Low to moderate | Good color accuracy, improving response |
| VA | 4-8 ms (varies by transition) | Moderate to high | Best contrast ratio among LCD types |
| OLED | ~0.1 ms | Virtually none | Self-emitting pixels switch near-instantly |
VA panels deserve special attention. While their contrast ratios are excellent (making them popular for movie watching and immersive gaming), they tend to have slower response times specifically for dark-to-light transitions. This means ghosting on VA panels is most visible in scenes with dark backgrounds and bright moving objects – a common scenario in many games.
OLED panels are the clear winner for ghosting. Because each pixel is self-emitting and can switch states almost instantly, ghosting is essentially a non-issue. This is one reason OLED monitors have become highly desirable for competitive gaming.
Refresh Rate and Ghosting
Refresh rate plays an interesting role. At 60Hz, the monitor displays each frame for about 16.7 milliseconds. At 144Hz, each frame is shown for only 6.9 ms, and at 240Hz, just 4.2 ms. Higher refresh rates mean smaller differences between consecutive frames, which reduces the perceived motion blur and ghosting. However, higher refresh rates also demand faster pixel response – if your panel cannot complete a color transition in 6.9 ms, a 144Hz refresh rate will still show ghosting.
The ideal combination is a high refresh rate paired with a fast response time. A 240Hz monitor with 1 ms GtG response time will produce significantly less ghosting than a 60Hz monitor with 5 ms response.
Overdrive: The Double-Edged Sword
Most monitors include an overdrive (OD) setting that speeds up pixel transitions by temporarily applying a higher voltage during color changes. This can meaningfully reduce ghosting, but there is a catch: if overdrive is set too aggressively, it causes a different artifact called inverse ghosting (or reverse ghosting/corona).
Inverse ghosting appears as a bright halo or overshoot artifact on the leading edge of moving objects – essentially, the pixel overshoots its target color before settling back. This looks unnatural and can be more distracting than the original ghosting.
Most monitors offer overdrive in multiple levels (Off, Low, Medium, High, or similar). The sweet spot is usually the middle setting:
- Off/Low: Some ghosting may be visible
- Medium: Usually the best balance – reduced ghosting without visible inverse ghosting
- High/Extreme: Often introduces inverse ghosting artifacts
Testing for Ghosting
If you want to evaluate ghosting on a monitor you already own or are considering, the UFO test at testufo.com is the standard tool. It displays moving objects at various speeds and lets you visually assess the severity of ghosting and inverse ghosting at different overdrive settings. Review sites also commonly use this test, making it easy to compare monitors objectively.
How to Choose
1. Check Response Time Specifications
For gaming, look for monitors with a GtG response time of 1 ms or less. Be aware that manufacturer-quoted response times are often best-case figures with aggressive overdrive enabled. Third-party reviews that measure actual response times across different color transitions give you a much more accurate picture of real-world ghosting performance.
2. Match Panel Type to Your Priority
If minimizing ghosting is your top priority and budget allows, OLED is the clear winner with near-zero ghosting. For LCD options, fast IPS panels offer a good balance of low ghosting, wide viewing angles, and strong color reproduction. VA panels are best suited for users who prioritize contrast and immersion over motion clarity. TN panels offer fast response but compromise on color and viewing angles.
3. Experiment with Overdrive Settings
After purchasing a monitor, spend time testing the different overdrive levels. Start at the medium setting, then adjust up or down based on what you see. If you notice bright halos around moving objects, your overdrive is too high. If you see dark trails behind moving objects, you could benefit from a higher setting. The right overdrive level depends on the specific panel and your sensitivity to motion artifacts.
The Bottom Line
Ghosting is the blurry trail that appears behind fast-moving objects on a display, caused by pixels that cannot change color quickly enough. It is most noticeable in gaming, sports, and other fast-motion content. Panel type is the biggest determining factor – OLED virtually eliminates ghosting, fast IPS panels handle it well, and VA panels tend to struggle with dark transitions. When shopping for a monitor, look beyond the headline response time spec and check third-party reviews for real-world measurements. A good overdrive setting can help, but the panel technology and its inherent response characteristics set the ceiling on how good motion clarity can be.