How to Run the Motion Blur Test
- Launch the test above and press F to enter fullscreen for the most accurate evaluation.
- Watch the moving object at each speed. The test cycles through slow, medium, and fast movement speeds. Each speed reveals different aspects of your panel's motion handling.
- Check the trailing edges. Are the edges of the moving object sharp, or do they smear into the background? Is there a dark shadow following the object?
- Note the difference at different speeds. Slower speeds show persistent sample-and-hold blur more clearly. Faster speeds reveal pixel response time ghosting.
Test with your monitor's overdrive settings at different levels — changing the overdrive setting in your monitor's OSD while running this test shows its direct effect on motion clarity.
Motion Blur vs Ghosting — Not the Same Thing
These two terms are often used interchangeably, but they describe completely different phenomena with different causes and different fixes:
Motion blur is an inherent property of all LCD displays caused by sample-and-hold rendering. Because LCD panels hold each frame for the entire frame duration (1/60th of a second at 60Hz, 1/144th at 144Hz), your eyes register the held image as a blur trail as they track moving objects. This blur exists even on a panel with 0ms GtG response time — it is a fundamental property of LCD technology, not a manufacturing defect. Higher refresh rates directly reduce it: 144Hz shows noticeably less than 60Hz; 240Hz less than 144Hz.
Ghosting is caused by slow pixel response time. When a pixel takes too long to transition from one color to the next, it leaves a dark or discolored smear behind a moving object — a trace of the pixel's previous state. Unlike sample-and-hold blur, ghosting depends on the specific colors involved and is often worst on dark-to-grey transitions, which is why VA panels ghost more than IPS.
You can have one without the other:
- A fast IPS panel at 60Hz: minimal ghosting but visible sample-and-hold blur
- A slow VA panel at 144Hz: reduced blur but visible dark trailing on dark scenes
What Affects Motion Blur
Refresh rate is the most significant factor. Each jump in refresh rate provides visible improvement:
- 60Hz → 144Hz: Dramatic difference — motion is noticeably sharper and more fluid
- 144Hz → 240Hz: Meaningful for competitive gaming and fast-paced content
- 240Hz → 360Hz: Marginal returns; relevant mainly for professional esports
Response time (GtG) determines ghosting severity. Panels with slow grey-to-grey transitions (typical of VA at 4–12ms for dark transitions) show dark trailing even at high refresh rates.
Motion blur reduction (ULMB, DyAc, ELMB): Strobe backlight technologies that flash the backlight only during the brief moment between frames. This eliminates sample-and-hold blur almost entirely — but introduces flicker and cannot be used simultaneously with variable refresh rate (G-Sync/FreeSync).
Understanding What You See in the Test
| What you see | Cause | Fix |
|---|---|---|
| Sharp edges, no trail | Excellent motion clarity | None needed |
| Dark smear behind object | Ghosting — slow pixel response (common on VA) | Increase overdrive setting |
| Bright halo ahead of object | Overdrive overshoot — overdrive too high | Reduce overdrive setting |
| Uniform blur, no trail | Sample-and-hold blur — normal on all LCDs | Higher refresh rate or motion blur reduction |
| Persistent blur at all speeds | Combined: slow panel + low refresh rate | Panel upgrade for high-motion use |
If you see a bright halo or white corona leading the moving object, your overdrive setting is too aggressive. Reduce the overdrive/response time setting in your monitor's OSD by one level and retest.
Frequently Asked Questions
What causes motion blur on monitors?
LCD motion blur has two causes: sample-and-hold persistence (the display holding each frame for its entire duration, causing blur as your eyes track motion) and pixel response time ghosting (pixels switching too slowly between colors, leaving a smear). The first affects all LCDs and is reduced by higher refresh rates. The second depends on the panel's GtG speed and overdrive settings.
What's the difference between motion blur and ghosting?
Motion blur is caused by sample-and-hold rendering — it affects all LCDs regardless of response time and is reduced by increasing refresh rate. Ghosting is caused by slow pixel transitions — it produces a colored or dark trail behind moving objects and is reduced by improving overdrive settings or choosing a faster panel. Both are visible in this test but at different speeds and for different reasons.
Does refresh rate affect motion blur?
Yes, directly. Each pixel is displayed for 1/Hz seconds — at 60Hz that's 16.7ms, at 144Hz it's 6.9ms, at 240Hz it's 4.2ms. Shorter display time = less blur trail as your eyes track movement. Going from 60Hz to 144Hz is the most impactful single upgrade for motion clarity.
How do I reduce motion blur on my monitor?
To reduce sample-and-hold blur: increase refresh rate, or enable motion blur reduction (ULMB/DyAc/ELMB) if your monitor supports it. To reduce ghosting/trailing: adjust the overdrive setting in your monitor's OSD — test each level with this tool to find the setting that minimizes trailing without introducing overshoot coronas.
What is ULMB / motion blur reduction mode?
ULMB (Ultra Low Motion Blur), DyAc (Dynamic Accuracy), and ELMB (Extreme Low Motion Blur) are strobe backlight technologies that flash the backlight off between frames, mimicking CRT persistence behavior. This eliminates most sample-and-hold blur at the cost of some brightness and the inability to use variable refresh rate simultaneously. It is most beneficial at 144Hz and above.