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Uncalibrated – Maximum Backlight Level
Determining the Q27G4XY’s maximum brightness took a bit of effort on my part. The OSD includes multiple dynamic contrast options, which I had to turn off to determine the panel’s native contrast. It also has a local dimming feature, which only affects brightness steps in the middle of the scale. It did not change black levels, peak output or contrast ratios. I measured a 25% window and a full field white pattern and got the same 343.7512-nit result. Black levels are excellent, enough for second place behind its sister display, the CQ27G4ZH. The static contrast ratio out of the box is therefore 4,209.3:1, higher than the VA average.
After Calibration to 200 nits
To solve a highlight clipping issue, I had to lower the contrast slider a bit, which reduced the ratio to 3,052.8:1. The Q27G4XY is still well ahead of even the best IPS screens and is only beaten by the other AOC in this test. The ANSI test was marred a bit by the corner hotspots I found earlier in the uniformity test. But it’s still visibly better than the four IPS monitors in the group. Overall, this is solid performance.
Test Takeaway: The Q27G4XY is firmly in the category of “not super bright but more than bright enough.” It won’t sear your retinas, but it will provide a deep contrasty image with true blacks and strong highlights that are sharply detailed.
