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 only have one other Ultra HD gaming screen in our database, the TN-based Acer XB280HK. The group's remaining displays run at QHD resolution. In the IPS category is Asus' PG279Q and MG279Q. The other Acer here is the excellent XB270HU. And to add a value-priced Ultra HD monitor to the mix, we've included Monoprice's UHD Matte. It's the only one without adaptive refresh.
None of the monitors will burn your retinas but they're all bright enough for most situations. The XG2700-4K places just below mid-pack. This is the max output for all the picture modes. If you select sRGB it drops the brightness control to 25, which corresponds to 120cd/m2. You can increase this value if you wish.
We left our favorite VA panels out of the comparison to make it fair. That tech is after all, in the minority. That being said, the XG2700-4K posts a decent max black level score. We haven't seen too many Ultra HD monitors with deep blacks.
While the ViewSonic doesn't win this comparison, it does have the highest contrast of any Ultra HD monitor we've tested, gaming or otherwise. While extra pixels are nice, we still consider image depth and dynamic range to be a more important mark of quality.
Uncalibrated – Minimum Backlight Level
Dropping brightness to zero yields a relatively useless light level of 15.0029cd/m2. It's not the lowest figure we've seen but it is well below the 50cd/m2 mark where you can actually see a decent image in a dark room. To achieve that, set brightness to 11.
The first two monitors are on top here thanks to their low minimum output, but as you'll see below, the XG2700-4K has great contrast throughout its backlight range.
The XG2700-4K stays consistent regardless of your chosen backlight setting. So far, we're seeing the kind of performance we expect at this price point.
After Calibration To 200cd/m2
The XG2700-4K has a uniformity compensation feature. It's an on or off proposition and as you can see, it cuts the white level almost in half. It's not something you'd expect to see in a gaming monitor but then, neither is the factory calibration nor the incredible color accuracy you'll read about on the next two pages. Speaking of uniformity, our tests show it to be exceptional so the compensation is completely unnecessary.
Uni Comp has almost no effect on black levels. It seems to do its thing at the brighter end of the scale.
In addition to halving light output, Uni Comp manages to cut contrast by about the same amount. There is definitely no good reason to use it. By the way, calibrated contrast is excellent even after tweaking the RGB sliders.
ANSI Contrast Ratio
The XG2700-4K is using a very high-quality panel with great screen uniformity and a properly engineered grid polarizer. It's rare that we see over 1000:1 ANSI contrast from any display that isn't VA. The MG279Q and XB270HU come in a close second.