Like all Asus gaming monitors, the XG27UQ defaults to its Racing picture mode. You can calibrate the image, but we found little need for adjustment. The factory calibration is sound and supported by an included data sheet.
Grayscale and Gamma Tracking
Our grayscale and gamma tests are described in detail here.
The out-of-box white point is slightly blue from 70% brightness and higher, but the error is almost invisible. Coupled with excellent gamma tracking, the XG27UQ makes our calibration-not-required list.
With a few tweaks to the RGB sliders however, the average error is now as low as any professional monitor can boast. Gamma remains solid with perfect tracking up to 70% and only a slight dip thereafter. This is excellent performance.
Asus includes an accurate sRGB mode that only has a slight purple error visible or 60% and higher brightness. Gamma tracks well at 2.2 except for 10% gray which is a little lighter than spec. If you’re a color purist, this mode is effective for SDR content. We wish it had adjustable brightness though, that slider is locked out and peak brightness is fixed at 180 nits.
With a default grayscale error of 3.01dE, the XG27UQ can be enjoyed without calibration. The slight blue tint we observed in test patterns is hard to spot in real-world content. If you can calibrate, or you choose to dial in our recommended settings, the error will be reduced to well below the visible threshold. 0.59dE is about as close to perfect as grayscale tracking gets.
In any case, gamma tracking is exemplary. Most of the luminance range is locked onto the 2.2 line with a little lightness from 70-90%. Again, this is hard to see in actual content. We have no complaints about the XG27UQ’s image accuracy. As you’ll see in the next section, color tracking is equally fine.
Color Gamut Accuracy
For details on our color gamut testing and volume calculations, please click here.
The XG27UQ’s Racing mode also means you’ll engage its full native color gamut for SDR content. Asus claims 90% coverage of DCI-P3, and our tests confirm that. In fact, you’ll get a little bonus blue, magenta and red. Green is slightly under but that is a barely visible error.
Calibration lowers the average error from invisible to slightly more invisible by virtue of improvements to secondary color hues. It doesn’t get much better than this.
The sRGB mode can’t be adjusted but its color is quite accurate. Aside from slight hue errors in cyan and magenta, there are no issues here. The XG27UQ is one of the few extended color monitors that has a truly usable sRGB mode.
A 1.99 Delta E (dE) score puts the XG27UQ into third place behind the more expensive PG27UQ and X27. None of these displays will give any user cause for concern; they are all extremely color accurate.
With only a slight under-saturation in green and cyan, the XG27UQ nearly fills the entire DCI-P3 gamut. Asus claims 90%, and our measurement of 89.27% is quite close. Again, only the more expensive X27 and PG27UQ boast more volume ,and that’s only by the slimmest of margins. The XG27UQ is perfectly qualified for color-critical work and will satisfy any gamer or entertainment seeker with its color reproduction.