Grayscale, Gamma & Color
Our grayscale and gamma tests are described in detail here.
Acer slips the word “professional” into its marketing for the BE270U, but clearly its calibration is not factory certified. The default grayscale runs a little blue though not grievously so. The error is visible but easily repaired with the right adjustments.
We tried engaging the sRGB mode, but it didn’t seem to affect grayscale at all. Plus, it locks out further adjustment and fixes output at 285cd/m2—too bright for us.
Back in User, we turned to the RGB sliders which are very precise and start at center-range. That means there’s no loss of contrast if you use them in a balanced fashion. A few clicks and we got the average error under 1dE, which is pro level performance.
The BE270U’s default white point starts a little higher than most at 4.06dE. That’s on the edge of acceptable, but if you can’t calibrate your monitor, use our settings. You’ll likely replicate our results. After adjustment grayscale tracks at a superb .72dE average. It doesn’t get much better than that.
Gamma tracking represents our principal complaint. There isn’t much to be gained by calibration here. Our adjustments brought the trace down a little but not enough to make a visual difference. The presets are too far apart to fix this. Selecting 1.8 puts the line about the same distance below 2.2. Ultimately, we thought the image looked best at the 2.2 setting. It’s a little darker than it should be, but since contrast is good and color is accurate and saturated, the overall effect on image quality is small. Still, it would be nice if Acer addressed this with a firmware update.
The range of gamma values isn’t too wide at only .29 from minimum to maximum, but the distance from a 2.2 average is larger than the majority of monitors we’ve reviewed. While this is a bit nit-picky on our part, the BE270U would look even better if its gamma were more accurate. We still like it, but if this were fixed we’d like it more.
Color Gamut & Luminance
For details on our color gamut testing and volume calculations, please click here.
We were fearful that the BE270U’s gamma tracking would have an adverse effect on color saturation tracking and luminance balance. Fortunately, Acer has engineered the monitor very well. By starting with a slightly over-saturated gamut and keeping luminance values balanced, the out-of-box color error is pretty low at only 3.34dE. The primaries look quite good, and there are only slight hue errors in the secondary colors, which can be fixed with a grayscale calibration. There is no need to adjust the six-axis controls.
sRGB doesn’t offer any gain in color accuracy. Its average error is almost exactly the same at 3.22dE. Since it also has no effect on gamma or grayscale, we don’t see a benefit. The User mode in its default state has identical quality and retains the full set of image adjustments.
After calibrating the User mode, the secondaries are now aligned correctly. Slight changes have occurred in the primary saturations but for the better. Color now looks a little more vivid than before. We have now maxed the BE270U’s quality potential.
Calibration takes the BE270U’s color gamut error to a low average of 2.19dE. While not quite in the professional realm, it’s more than qualified for premium business users and gamers. The darker gamma, while not ideal, results in a slightly more vivid presentation than usual. Some users are likely to prefer this over a super accurate display. Again, we’re talking about very small differences here.
Thanks to slightly over-saturated primaries, the BE270U can render over 100% of the sRGB color gamut. We’d always rather see color go beyond the spec rather than fall short. That way, a custom profile can dial it back to the correct targets. You can’t add color that isn’t there, but you can reduce it when it’s over the line.