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Uncalibrated – Maximum Backlight Level
The XG27ACS has prodigious output with over 440 nits available for SDR content. This can be achieved with a full screen white field, so there is no variable brightness happening. You can easily make this monitor bright enough for outdoor use or when sitting next to a sunny window. Black levels are about average for IPS tech, as is the contrast ratio of 1,005.7:1. In this group, the Lenovo has a distinct advantage with its VA panel that delivers almost 4,400:1 contrast. And a few IPS monitors boast more dynamic range. The ASRock stands out in particular with almost 1,500:1.
After Calibration to 200 nits
Calibration in the XG27ACS’s case requires reducing the brightness slider to 200 nits. Contrast remains the same, right at the class average of 1,000:1. ANSI contrast is also at the IPS average of just under 1,000:1. The XG27ACS’s 941.8:1 score is a bit behind the other panels with the Lenovo’s VA screen again topping the chart with almost 3,700:1.
Test Takeaway: If you want high contrast, IPS is not the right choice. The XG27ACS delivers strongly in other areas like color and video processing. If you want deep blacks and broad dynamic range, you’ll need VA or OLED for a significant improvement. But for $300, Asus delivers a solid monitor.
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