Grayscale, Gamma & Color
The Predator X34P delivers the same color accuracy as the X34, but takes a slightly different approach to gamma. We’ll explain everything in the next round of tests, detailed below.
Our grayscale and gamma tests are described in detail here.
From the factory, the X34P is set to its Standard picture mode. But making any change, even to brightness, kicks the monitor to User. A full set of calibration controls are available, including a color management system. There is no sRGB mode, but it isn’t too difficult to dial things in to D65. You can choose one of the preset values which vary in accuracy from poor to good, or adjust the RGB sliders which start at center-range. This allows a balanced adjustment that maintains contrast. We also had to reduce the contrast slider from 50 to 40 to eliminate detail clipping in the brightest areas of the image. Our adjustments take the X34P's performance from average to excellent.
The Predator X34P starts out at 4.08dE, which is a little lower than average among premium gaming screens. It’s a small step backward from the X34 which doesn’t need calibration, at only 1.62dE. We think the results are worth it however because the new monitor uses gamma to better advantage.
Our initial measurements showed all the Predator X34P’s gamma presets to run higher than stated. The default is 2.2, but it tracks closer to 2.5. A too-high contrast control causes a lot of clipping from 80% brightness and higher. This issue needs to be addressed, and has a significant impact on image quality. The two fixes are to lower contrast from 50 to 40 and set the gamma option to 1.9. That results in perfect tracking at the 2.4 level. It’s a little darker than we’d prefer from an IPS panel, but it works in this case. And it’s crucial to make this change for the sake of color saturation accuracy, which we’ll show you next.
A .09 deviation in gamma values is about as close to perfect as any display can boast. Only the Asus XG35V manages to edge out the Predator X34P, and then only by the slimmest possible margin. In the second chart, we calculated the review subject’s deviation from 2.4, while the other panels show their gap to 2.2. It’s clear to us that Acer intends to run this panel at a higher gamma level than normal, despite what the OSD labels say. That’s fine, as long as one makes the proper tweaks to balance every setting.
Color Gamut & Luminance
For details on our color gamut testing and volume calculations, please click here.
The incorrect gamma and contrast settings show up in the first two charts. The 100% saturation points are close to target, red and green a little over, and blue a little under. But look at the inner measurements. Most are over-saturated, and that is where the majority of image information lies. Because the 80% measurement is so close to the 100% target, a lot of detail will be lost in brighter material. Luminance levels aren’t too high, but they could be better.
The second set of charts is just what we’re looking for. Every point is on-target except 100% red which is a little over-saturated, and 100% blue which is still under. That primary is OK though, because luminance has been increased to compensate. The best part is the inner points, which are right where they should be. The improvement in picture quality here is easy to see.
Our changes take the average color error from 3.67 to 1.16dE. That doesn’t seem like a lot, especially considering that 3.67 is barely visible. But when we went back and forth between modes, the difference became obvious. Calibration makes a huge difference, and after using a properly-adjusted monitor for a few days, that difference seems even greater.
Thanks to the over-saturated red and green primaries, gamut volume is slightly above the full sRGB spec at 103.14%. This is great for gaming and video, since you get a subtle bit of extra richness without things becoming unnatural. You could dial it down with the saturation control, but then blue would be too far off the mark. For color-critical situations, a software profile is the right choice. The Predator X34P has a slight edge over the X34 in overall color accuracy and image quality, which is what we'd hope given the newer X34P is newer by two years.
MORE: Best Gaming Monitors
MORE: How We Test Monitors
MORE: All Monitor Content