sRGB Test Bench

All calibration measurements are done using SpectraCal’s CalMAN 5.3 software with a custom workflow. Measurements are done using a C6 colorimeter that is first profiled against an i1Pro spectrometer to ensure accurate results. There are two sets of targets we use. Pre-Calibration and our first calibration aim for 200 cd/m^2 with an sRGB gamut and a gamma of 2.2. This is a common real-world setting for a display. The final target changes the white level to 80 cd/m^2 and the gamma curve to the tougher AdobeRGB standard.

 

Pre-Calibration

Post-Calibration,
200 cd/m^2
Post-Calibration,
80 cd/m^2
White Level (cd/m^2) 204.1 201.0 84.3
Black Level (cd/m^2) 0.275 0.281 0.131
Contrast Ratio 742:1 716:1 644:1
Gamma (Average) 1.90 2.17 2.45
Color Temperature 6702K 6629K 6506K
Grayscale dE2000 2.74 0.44 0.81
Color Checker dE2000 3.37 1.53 1.65
Saturations dE2000 2.41 1.42 1.50

For this review I’ve switched from taking 21 measurement points to taking 256 levels for grayscale. It provides a much better level of detail than before. Color measurements can’t be measured at the same level of detail, but I do measure them as much as possible.

Using the "Warmish" color temperature setting, we see a good RGB balance before calibration. What isn’t as good is the gamma point, which starts out at 1.6, rises up to 2.0 and then falls down quickly at the top end. This causes crushing of highlights, where values from 90%-100% will look almost identical, and causes shadows to be washed out as well. Colors also have errors with colors on the Green-Yellow-Red side of the CIEuv chart being over-saturated. This also causes the skin tones to be exaggerated.

Post-calibration at 200 cd/m2 the RGB balance is improved but more importantly the gamma is far improved. The gamma is so far off the 2.2 target above 90% that we can’t fully correct it here, but calibration does a good job of fixing it overall. The dE2000 errors fall and are all below 2.0 now with an average of 0.44 that is very good. Color errors improve but there is still a lot of over-saturation in oranges, yellows, greens, and reds that cause visible issues. The lower half of the color gamut is much more accurate.

When we target 80 cd/m2 we see more issues with the gamma, as the lower light output provides us less range to fix the gamma through the hardware LUTs. The grayscale dE2000 is higher as a result but still below 2.0 everywhere. Colors have the same issues, as the green line is hidden behind the yellow line on the saturations chart, but it is otherwise almost the same as it is with 200 cd/m2.

The pre-calibration numbers are okay for the QNIX, but the main thing that holds it back is the gamma preset it utilizes. It makes it hard to hit the gamma target of 2.2 that we look for and means you can see some highlight clipping, even after calibration.

Brightness and Contrast Display Uniformity
Comments Locked

85 Comments

View All Comments

  • lazarpandar - Friday, April 11, 2014 - link

    HD refers to 1280x720 so it logically follows that QHD refers to 2560x1440. Look at some laptop spec sheets, they all claim HD for 1366x768 and Full HD for 1920x1080. This review is not confusing in any way, it just sounds like you guys weren't very familiar with the terminology (which is admittedly kind of confusing).
  • LordOfTheBoired - Sunday, April 13, 2014 - link

    The terminology isn't confusing. It's stupid, and it always has been. The *GA line isn't any better(it's actually far worse, for various reasons).

    Specify resolution with a perfectly good X by Y spec, or don't bother at all. Leave the cute nicknames on the mass-marketing bullet lists where they belong.
  • WithoutWeakness - Friday, April 11, 2014 - link

    HD = 1280x720
    FullHD (FHD) = 1920x1080
    QuadHD (QHD) = 2560x1440
    UltraHD (UHD, 4K) = 3840x2160

    The confusion has come in when people have begin referring to 1920x1080 as "HD". By that definition, "QuadHD" then implies 4x1080p or 4K, which is incorrect. QuadHD has always been 2560x1440. So the confusion doesn't come from how the article is written - it comes from the incorrect definition of "HD" that has perpetuated over the last few years as new confusing acronyms are coined for higher-resolution displays.
  • phoenix_rizzen - Friday, April 11, 2014 - link

    The confusion comes in when people refer to the vertical resolution for years and years (480p, 720p, 1080p) and then switch to using the horizontal resolution (2K, 4K), especially considering those monikers are off by several hunder to a thousand pixels.

    If everyone just keeps using the vertical resolution, then nobody gets confused.
    480p
    720p
    1080p
    1440p
    2160p

    Nice, neat, simple. Changing definitions in the middle is what's causing all the issues.
  • hennwei - Friday, April 11, 2014 - link

    4K sounds way cooler though. and when it sounds cooler, it sells more. kaching!
  • skifiddle - Sunday, April 13, 2014 - link

    It is Cha-ching as in where it is made.
  • Treckin - Thursday, April 24, 2014 - link

    definitely cha ching as in the noise an antique cash register made...
  • Laststop311 - Friday, April 11, 2014 - link

    4k ultrade hd is sometimes referred to as QFHD quad full hd
  • coburn_c - Friday, April 11, 2014 - link

    Panel grading refers to manufacturing defects, these ebay panels are usually B grade on a scale of A+,A,A-,B,C. Also WQHD is 1440p as the keywords, article, charts, and text state...
  • blackoctagon - Thursday, May 1, 2014 - link

    They're not only sold on eBay and the panel grade is actually A-

Log in

Don't have an account? Sign up now