Page 1:NEC EA274WMi: A High-Performance 27" Monitor
Page 2:Packaging, Physical Layout, And Accessories
Page 3:OSD Setup And Calibration Of The NEC EA274WMi
Page 4:Measurement And Calibration Methodology: How We Test
Page 5:Results: Brightness And Contrast
Page 6:Results: Greyscale Tracking And Gamma Response
Page 7:Results: Colour Gamut And Performance
Page 8:Results: Viewing Angles And Uniformity
Page 9:Results: Pixel Response And Input Lag
Page 10:NEC EA274WMi: Some Unique Features
Measurement And Calibration Methodology: How We Test
To measure and calibrate monitors, we use an i1Pro spectrophotometer, a Spectracal C6 colorimeter, and version 220.127.116.114 of SpectraCal’s CalMAN software.
The i1Pro is very accurate and consistent measuring colour on all types of displays, regardless of the backlight technology used. When we just need a luminance value, the C6 works better, especially in low light.
For patterns, we employ an AccuPel DVG-5000 video signal generator. This approach removes video cards and drivers from the signal chain, allowing the display to receive true reference patterns. Connections are made via HDMI.
The AccuPel DVG-5000 is capable of generating all types of video signals at any resolution and refresh rate up to 1920x1080 at 60 Hz. It can also display motion patterns to evaluate a monitor's video processing capabilities, with 3D patterns available in every format. This allows us to measure colour and greyscale performance, crosstalk, and ghosting in 3D content via the 3D glasses.
The i1Pro/C6 is placed at the center of the screen (unless we’re measuring uniformity) and sealed against it to block out any ambient light. The AccuPel pattern generator (bottom-left) is controlled via USB by CalMAN, which is running on the Dell XPS laptop on the right.
Our version of CalMAN Ultimate allows me to design all of the screens and workflows to best suit the purpose at hand. To that end, I’ve created a display review workflow from scratch. This way, we can be sure and collect all the necessary data with a concise and efficient set of measurements.
The charts show us the RGB levels, gamma response, and Delta E error for every brightness point from zero to 100 percent. The table shows us the raw data for each measurement. And the area in the upper-left tells us luminance, average gamma, Delta E, and contrast ratio. The individual charts can be copied to the Windows clipboard to easily create graphics for our reviews.
Every primary and secondary colour is measured at 20-, 40-, 60-, 80-, and 100-percent saturation. The colour saturation level is simply the distance from the white point on the CIE chart. You can see the targets moving out from white in a straight line. The farther a point is from center, the greater the saturation until you hit 100 percent at the edge of the gamut triangle. This shows us the display’s response at a cross-section of colour points. Many monitors score well when only the 100-percent saturations are measured. Hitting the targets at the lower saturations is more difficult, and factors into our average Delta E value (which explains why our Delta E values are sometimes higher than those reported by other publications).
- NEC EA274WMi: A High-Performance 27" Monitor
- Packaging, Physical Layout, And Accessories
- OSD Setup And Calibration Of The NEC EA274WMi
- Measurement And Calibration Methodology: How We Test
- Results: Brightness And Contrast
- Results: Greyscale Tracking And Gamma Response
- Results: Colour Gamut And Performance
- Results: Viewing Angles And Uniformity
- Results: Pixel Response And Input Lag
- NEC EA274WMi: Some Unique Features