Brightness & 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 finally have six Ultra HD monitors with adaptive refresh in our database and they’re all represented here today. The recently-reviewed Acer Predator XB271HD and XB321HK, along with ViewSonic’s XG2700-4K stand for the IPS category. The remaining screens use TN parts and include Acer’s XB280HK and AOC’s U2879VF.
Asus claims a max output of 330cd/m2 for the MG28UQ but we couldn’t measure a value higher than 275. Perhaps if you turned the contrast slider all the way up, but that would clip detail and destroy white point accuracy. Nonetheless, the panel is plenty bright for typical indoor environments. The anti-glare layer maintains a solid image even when sunlight is coming in the window.
The max black level is mid-pack, though none of these screens will be setting any contrast ratio records. They’re all pretty close in performance.
Contrast is a tad low for our taste, but the other two TN screens fare worse. The top three IPS panels offer greater dynamic range and image depth but that comes at a higher price.
Uncalibrated – Minimum Backlight Level
The backlight doesn’t have to go quite this low. There aren’t too many instances where you’d want to play games or do anything else at an output level of 33.5961cd/m2. To raise brightness to 50cd/m2, move the slider to 11.
The black level tracks with the overall backlight intensity so a third-place finish in this test doesn’t mean better contrast. As you’ll see below, that is fairly consistent.
Contrast remains reasonably constant for all the monitors in the group. It’s rare that we see more than a 10 percent variation throughout the backlight’s range for any modern display.
After Calibration to 200cd/m2
We had to reduce the contrast slider just a little to improve grayscale tracking and that hurt the calibrated black level. For maximum dynamic range in an Ultra HD monitor, IPS is clearly the better choice. TN offers speed and value but at the sacrifice of image depth.
We could improve this number a little if we turned contrast back up or engaged the ASCR (dynamic contrast) feature. 753.6:1 is the MG28UQ’s native result. If image depth is a deal-breaker for you, IPS is the better choice. The monitor with the best balance of price and contrast performance is the ViewSonic.
ANSI Contrast Ratio
The ANSI test demonstrates that the MG28UQ is a well-made panel, and it actually measures a little higher than its sequential result which is rare. IPS is still the tech to beat though. While the difference is small, contrast is the metric we consider most important when choosing a monitor. Even a little more can make a visible impact on image quality.