Results: Brightness And Contrast
Before calibrating any panel, we measure zero and 100-percent signals at both ends of the brightness control range. This shows us how contrast is affected at the extremes of a monitor's luminance capability. We do not increase the contrast control past the clipping point. While that would increase a monitor’s light output, the brightest signal levels would not be visible, resulting in crushed highlight detail. Our numbers show the maximum light level possible with no clipping of the signal.
All three recently reviewed gaming monitors are represented in this round-up: the RL2460HT, plus BenQ’s XL2720Z and Asus’ VG248QE. We also have three professional QHD screens: NEC’s PA272W and EA274WMi, along with ViewSonic’s VP2772.
The RL2460HT’s default picture mode is Fighting and that's where you'll find the brightest image. Our measurement of 302.0166 cd/m2 exceeds BenQ’s spec by over 20 percent. There are a couple of color gamut issues in that mode, plus, grayscale and gamma accuracy are merely average. If you switch to Standard or sRGB, you still get around 240 cd/m2, which is decent performance. This monitor isn’t a light cannon. It is bright enough for any gaming situation we can think of, though.
TN is still the go-to panel technology for black levels, as our results show. Even though IPS is getting better, it isn’t quite there yet. And as you’ll see later, TN retains its edge for gamers with lower response times and less input lag.
The only display to beat BenQ's RL2460HT in this group is Asus’ VG248Q high-refresh rate model. Still, 1170.7 to 1 is an excellent number that sails right over our benchmark figure of 1000 to 1. Once you dial in gamma properly, this screen delivers a nice image with plenty of detail and pop.
We believe 50 cd/m2 is a practical minimum standard for screen brightness. Any lower and you risk eyestrain and fatigue. The RL2460HT puts out 45.5816 cd/m2 at its lowest Brightness setting. Conceivably, you could use the screen like that in a room devoid of ambient light. As you’ll see in the next two charts, black levels and contrast maintain excellent consistency.
A result of .0400 cd/m2 represents a great black level, considering the minimum white level is over 45 cd/m2. The two NECs beat the RL2460HT only because they bottom out at less than 20 cd/m2. If you like playing games with the brightness at the bottom, you may want to experiment with different gamma presets to make sure no shadow or highlight detail is lost.
If you ignore Asus’ freakish result, the BenQ becomes one of our top contrast performers. After checking the ratio at 80, 120, and 160 cd/m2, we found that you’ll always see about 1100 to 1, yielding the kind of consistent performance we look for in any monitor.
Since we consider 200 cd/m2 to be an ideal point for peak output, we calibrate all of our test monitors to that value. In a room with some ambient light (like an office), this brightness level provides a sharp, punchy image with maximum detail and minimum eye fatigue. On many monitors it’s also the sweet spot for gamma and grayscale tracking, which we'll look at on the next page.
In a darkened room, some professionals prefer a 120 cd/m2 calibration, though we've found it makes little to no difference on the calibrated black level and contrast measurements.
The calibrated black level stays nice and low at .2026 cd/m2. We made minor changes during calibration, so minimum brightness and on/off contrast aren't much different.
Calibrated contrast only takes a slight hit down to 993.8 to 1. We couldn’t see any difference in image quality other than the color improvement that always accompanies calibration. Some tradeoffs have to be made with regards to gamma to achieve the very best contrast. We’ll talk about them on the next page.
ANSI Contrast Ratio
Another important measure of contrast is ANSI. To perform this test, a checkerboard pattern of sixteen zero and 100-percent squares is measured, yielding a somewhat more real-world metric than on/off readings because we see a display’s ability to simultaneously maintain both low black and full white levels, factoring in screen uniformity, too. The average of the eight full-white measurements is divided by the average of the eight full-black measurements to arrive at the ANSI result.
We’re seeing more and more displays achieving higher and higher ANSI contrast results. It’s a trend we like because it means greater image depth in more kinds of content. When a relatively inexpensive monitor like the RL2460HT can match the performance of displays costing three and four times as much, you know progress is being made. Prices may not be dropping to everyone’s satisfaction, so we have to cheer about increased quality and performance.