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Brightness And Contrast
To read about our monitor tests in-depth, please check out Display Testing Explained: How We Test Monitors and TVs. Brightness and Contrast testing is covered on page two.
Uncalibrated – Maximum Backlight Level
We can’t quite fill the group with G-Sync-capable monitors. But the empty spaces are occupied by 24-inch 144Hz screens, including BenQ’s XL2430T, LG’s 24GM77 and AOC’s G2770PQU. G-Sync is represented by the Asus PG278Q (ROG Swift) and AOC G2460PG.
Because of the XL2420G's dual-mode nature, we’re showing data from both the G-Sync and Classic modes. There are significant differences in light output, contrast, gamma and color. Fortunately you can set up each mode independently if you wish. We’ll walk you through everything.
The highest light output comes from Classic mode with the Brightness option maxed. Ordinarily we’d say that’s a good thing when using blur reduction. But in the XL2420G’s case, the hit to output borders on tremendous at 65 percent.
There is a pulse-width adjustment in G-Sync mode, but it can only be lowered, which means the monitor becomes even darker. While the output levels are still useable, you’ll have to turn your room lights down (or off) for best results.
It stands to reason that the best black levels occur when blur reduction is turned on. If you like to play in the dark, the image looks pretty good with detail-rich shadows. Thanks to accurate low-end gamma, it’s easy to see the darker areas of your content.
In Classic mode, contrast is unaffected by blur reduction. The same is not true in G-Sync mode, however. You lose about 14-percent contrast without blur reduction and almost 37 percent with it. The upside is that, at high refresh rates, you can live without the feature. And it’s well worth sacrificing for better contrast. We prefer using the XL2420G in its 144Hz mode all of the time.
Uncalibrated – Minimum Backlight Level
The above result represents Classic mode with blur-reduction turned off. If you turn it on, peak output drops to 35.8429cd/m2, which is a little too dim for us. Our favorite screen for dark-room gaming is Asus' ROG Swift and its ideal 51.9157cd/m2 minimum output.
A bright backlight means higher minimum black levels. A result of .0992cd/m2 is still pretty low, however. What's important is that contrast remains consistent, as you’ll see in the next chart.
A result of 1032.1:1 reflects minimal change from the maximum. And that holds true for both the Classic and G-Sync modes. You can set the backlight to your preference, maintaining the same image depth and contrast regardless of output.
After Calibration to 200cd/m2
Our calibrated output results come from the Classic mode. Without blur reduction, G-Sync mode offers about the same black level, albeit with less peak output. That explains the difference in overall contrast.
Calibrated contrast is only four percent lower than the max result in Classic mode. G-Sync mode contrast is 857.9:1, reflecting close to the same 14-percent drop we saw above. All of the monitors are pretty similar in this metric. You won’t see a huge difference when comparing them side-by-side. Of the G-Sync-capable screens, Asus offers the best calibrated contrast. But LG’s 144Hz model takes the overall prize.
ANSI Contrast Ratio
BenQ uses a good-quality panel in the XL2420G. Such high ANSI contrast makes this a great display for gaming and video content alike. The only screen lagging here is AOC's G2460PG.
