Page 1:Planar PXL2790MW: Clarity, Performance, And Accuracy In QHD
Page 2:Packaging, Physical Layout, And Accessories
Page 3:OSD Setup And Calibration
Page 4:Measurement And Calibration Methodology: How We Test
Page 5:Results: Brightness And Contrast
Page 6:Results: Grayscale Tracking And Gamma Response
Page 7:Results: Color Gamut And Performance
Page 8:Results: Viewing Angle And Uniformity
Page 9:Results: Pixel Response And Input Lag
Page 10:Planar's PXL2790MW Gets Top Marks For Clarity And Performance
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 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.
Our comparison group for this review is the last six displays that Tom's Hardware reviewed.
It seems like every new monitor we receive is brighter than the last. When you turn the PXL2790MW’s brightness control to 100, you are rewarded with over 445 cd/m2 of luminance. That's so bright in our test environment as to border on painful. Even with a lot of ambient light, fatigue quickly sets in if you try to use the display dialed all the way up.
It also has a negative impact on the maximum black level.
Considering the extreme output level, .3816 cd/m2 isn’t a bad result, though. If you max out brightness like this, blacks look grayer, even if the overall contrast is decent.
Here’s the final contrast result.
This is decent on/off contrast for such a bright display. One thing that could make the PXL2790MW even more versatile is separate backlight and brightness controls. That way, we could improve contrast by turning down the backlight, but leave the brightness at a level that preserves detail. The monitor has plenty of dynamic range; it’s just concentrated at a brightness level that is too high.
For the next group of measurements, we turn down the brightness control to its minimum setting and leave the contrast unchanged. The PXL2790MW measures 174.7655 cd/m2, which is way above our minimum standard of 50 cd/m2. Below that, you risk fatigue and eyestrain. However, the monitor is too bright for a completely dark room. To reinforce our above comment about dynamic range, there is plenty available. It's just at a higher brightness level than necessary. A backlight control would allow the user to pull that down while retaining (or even improving) the display’s already solid contrast.
A .1480 cd/m2 measurement is respectable, but it could be so much lower if the overall brightness level weren’t so high. We do experience a quality black level, though. Dark areas in movies and games look nice and detailed, mainly due to the PXL2790MW’s excellent gamma performance.
We’ll wrap up this section with the minimum contrast comparison.
The minimum contrast number is only slightly higher than the maximum one, which shows consistency. While our result is very good, there is potential for even better contrast with the addition of a backlight adjustment, or a brightness control with greater range.
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. It's also the sweet spot for gamma and grayscale tracking, which we'll look at on the next page.
We start with the calibrated black level. This can sometimes rise a bit from the monitor’s default state. We consider the tradeoff in contrast well worth the gain in color accuracy.
After calibration, the PXL2790MW’s black level is only a little higher than its minimum number, mainly because of the high minimum white level value. With a backlight control, it would be possible to lower the peak white enough to generate much better blacks.
Here are the final calibrated contrast numbers.
While 899.3 to 1 contrast won’t break any records, it still represents a solid performance. Thanks to its unequaled clarity and nearly perfect gamma, the PXL2790MW’s perceived contrast is a good deal higher than the measurements would indicate.
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. Our benchmark is somewhat more real-world than on/off measurements because it tests a display’s ability to simultaneously maintain both low black and full white levels, and factors in screen uniformity. 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.
Although a result of 893.2:1 is pretty good, it could have been much better had there not been hotspots on the left side of the screen. The black squares there are visibly brighter than the rest. The PXL2790MW does suffer from a black uniformity issue, at least in the sample we tested. Had our measurements been a little more consistent, the ANSI contrast would easily have topped 1000:1.
- Planar PXL2790MW: Clarity, Performance, And Accuracy In QHD
- Packaging, Physical Layout, And Accessories
- OSD Setup And Calibration
- Measurement And Calibration Methodology: How We Test
- Results: Brightness And Contrast
- Results: Grayscale Tracking And Gamma Response
- Results: Color Gamut And Performance
- Results: Viewing Angle And Uniformity
- Results: Pixel Response And Input Lag
- Planar's PXL2790MW Gets Top Marks For Clarity And Performance