Grayscale Tracking And Gamma Response
Our grayscale and gamma tests are described in detail here.
This chart represents the Warm color temp preset. It's still visibly cool with a blue tint that only goes away at the highest luminance level. Since most users don't calibrate their monitors we'd like to see a better out-of-box result than this. Ultimately, it won't be a deal-breaker for most buyers but most of the gaming monitors we've reviewed perform a little better in their default state.
One of the color temp options is labeled "sRGB" and we thought it might clean up the chart somewhat but as you can see, the result is nearly the same. Selecting this preset locks out the Brightness, Contrast and Gamma controls, which causes further inaccuracies. The best performance is found in the User mode shown below.
We observed unusual behavior from the RGB sliders when calibrating. Normally when dialing in the 80 percent luminance pattern, the rest of the points line up too. In this case, there is an overall improvement but errors are still there at 10 to 40 and 100 percent. The visual assessment looks OK but most monitors we review can get all the errors under 2dE. For some reason the G2770PF doesn't respond to adjustment the same way.
Here is our comparison group.
A 6.3dE average is fairly high no matter what group you're comparing to. We realize that gaming monitors prioritize speed and video processing over color accuracy but there's no reason an out-of-box result closer to 3dE shouldn't be the norm.
Calibration does make a noticeable improvement so we think it's well-worth the effort. The only way to improve accuracy further is with a software LUT generated by CalMAN or Spyder.
The G2770PF has three gamma presets and each curve is slightly different. Above we're showing you the default setting. It runs too light across the board and robs the image of a little depth.
The sRGB preset locks the gamma to the same setting but it tracks a little closer to 2.2 than before. This is acceptable performance but whites still look too blue for our taste.
Gamma 2 isn't an ideal result either but at least the values bracket 2.2. This curve means you'll see a little more highlight and shadow detail, which is a good thing. Overall, the image still looks pretty good.
Here is our comparison group again.
The range of values is wider than the rest but again, the visual difference is small. Since the G2770PF has such good sequential and ANSI contrast, these errors aren't a big deal.
We calculate gamma deviation by simply expressing the difference from 2.2 as a percentage.
Gamma tracking may not be ruler-flat but it does stay close to an average of 2.2. Now we'll see how color saturation and luminance are affected.