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 contrast past the clipping point. While doing this 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.
The comparison group today consists of gaming-oriented monitors running at 120 or 144 Hz, with the exception of BenQ’s RL2460HT, which tops out at 60 Hz. We have Asus’ VG248QE, BenQ’s XL2720Z, AOC’s G2460PQU, and the lone IPS screen, an Overlord Tempest X270OC.
A gaming monitor, especially one with a backlight strobe, needs plenty of output. Asus' PG278Q delivers. It’s rated at 350 cd/m2, but we measured nearly 400 in our test. Of course, enabling ULMB drops this figure by about 57 percent.
A bright backlight usually means an elevated black level. The Swift just cracks the .4 cd/m2 mark, similar to the brightest competitor, AOC’s G2460PQU.
Contrast is pretty solid at just under 1000 to 1. And as we'll point out in subsequent tests, it stays fairly consistent regardless of brightness or level of blur-reduction.
We believe 50 cd/m2 is a practical minimum standard for screen brightness. Any lower and you risk eyestrain and fatigue. The PG278Q bottoms out at 51.9157 cd/m2. This is a great light level for playing games in total darkness as long as you don’t use the ULMB feature. As you’ll see below, black levels and contrast hold up extremely well too.
Minimum output is right in the middle of the group at .0540 cd/m2. The main takeaway is that IPS is still a bit behind TN in the black level department.
Contrast remains consistent at 960.7 to 1. You’re able to use the Swift in pretty much any room environment we can think of. And you can tailor the brightness to your preference without having to worry about a contrast sweet spot.
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), you get a sharp, punchy image with maximum detail and minimum eye fatigue. On many monitors, this is also the sweet spot for gamma and grayscale tracking, which we'll look at on the next page.
In a dark room, many professionals prefer a 120 cd/m2 calibration. We have found it makes little to no difference on the calibrated black level and contrast measurements, though.
Calibration has little effect on black level or contrast. The adjustments we made were small, so the result is not surprising.
We only took a slight hit to contrast with a final value of 929.6 to 1. That's mainly because we can only reduce the RGB levels, not increase them. It’s always best if the controls start at their center positions.
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.
The PG278Q finishes fifth in an extremely tight race. Those middle four screens will look identical to the naked eye, though, and 915.2 to 1 is a solid result. This display shows excellent build quality and an image with good depth and dimension.