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I have a NEC PA241W monitor with stock x-rite calibrator. Recently I've re-calibrated it after several years of working with the following target values as recommended in one of online courses:

  • White point: 6000 K;
  • Display luminance: 120 cd/m^2;
  • Gamma curve: 2.2

and got the following chart (cyan triangle is an sRGB gamut and yellow one is an Adobe RGB):

enter image description here

So, my question is this normal for wide-gamut monitor to have even smaller coverage than sRGB? As far as I can remember, when I calibrated it for the first time, the coverage was wider than sRGB. I also heard that calibrators are working more worse from year to year, so can it be somehow related?

I used for calibration the following parameters and selected the result profile as default for the system and Photoshop: enter image description here enter image description here

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No, this is not normal.

I had an even older NEC wide-gamut monitor with very similar specs which worked for me for 8 years. Even after all this time, its measured gamut was still very close to AdobeRGB. In fact, it stabilised so that validation didn't require re-calibration for years on end.

It is more likely that the colorimeter degraded, if you had a very different result with the same one years ago. But my Datacolor Spyder 3 lasted those 8 years and showed consistent results, and was later verified with a new Spyder 5.

I don't know specifically about your X-Rite model, but many older calibrators are not well compatible with the wide-gamut displays, esp. with the newer LED ones: they cannot correctly measure the most saturated colours. You need to check if NEC specifically lists your model as compatible with this monitor.

To partly mitigate this problem, SpectraView II can skip measuring the primaries (the most saturated colours by definition) and rely on their supposed values. This is controlled by the last option on your last screenshot. Try to switch it to Automatic and repeat calibration, and see if you have a different result. It seems that only the green measurement is affected.

Also check the correction curves after you re-calibrate (the 3rd tab on the first screenshot). On a good NEC (or any professional) monitor, they should be smooth and almost linear.

Finally, although this must be unrelated to the problem, I don't know why one would use the 6000K white point. Apparently this is meant to be sort of a compromise between the print/art (5000K) and standard display (6500K). I would rather recommend a proper standard setting, most likely 6500K for you.

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If this is a 10 year old calibrator that came with a 10 year old monitor, verify it against a calibrator of recent manufacture. Some calibrators are known to use filter materials which, while high grade, have aging issues severe enough to make them unserviceable after several years.

  • Thanks for the answer! So in general it could be said that a gamut curve I have shouldn't look like this? Now I have doubts whether I should've chosen a recommended automatic option as a source of primary color instead of a calibration sensor measurements. – errorist May 7 at 18:17
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I have an NEC PA271W, still works great, still wide gamut. SO:

1) Why are you setting whitepoint at 6000? D65 (6504°) would be the standard for Adobe98 and sRGB among others. When you try to force the monitor into a color space that is not it's default (i.e. it's D65 Adobe98 primaries) it will cause the resultant apparent gamut to shrink.

2) I use an X-Rite i1-DisplayPro. It is better for wide-gamut, and the filters are supposed to be "lifetime". The filters in the older i1Display2 were not so great for wide gamut (though the one bundled with NEC had special filters) but ALSO, the filters in the display2 are known to drift.

3) BasICColor Display software is excellent, and may give you better results than Spectraview. Consider getting the XRite i1-DisplayPro and BasICColor Display software.

4) The NEC monitor has a "self calibrate" function that adjusts for aging to correct the yellowing that happens. Run that (takes half an hour) and see if that fixes things. I did that about a year ago and it made a big difference.

In short: Run the self-calibrate, then profile for Adobe98 standard (D65).

  • Thanks for the answer. – errorist May 9 at 12:31
  • I'll answer accordingly: 1) Prior to calibrating I've took a course from a merited Russian tutor Alexey Shadrin. The point is that one should choose a temperature of target white point by the formula: adaptation light temperature in K + 1000K. This is something because of cognitive discoloration of source ambient lightning or something. Didn't remember details but remembered this formula. Among parameters were luminance equal around 120 cd/m^2 and gamma 2.2. – errorist May 9 at 12:48
  • 2) As you mentioned a correct device model, I'm using bundled custom X-Rite i1 Display v2 designed for these wide gamut monitors so by design it should handle it correctly out of the box. Nevertheless I totally agree about aging as a known "issue" of this type of devices. Considering everything above now I can say that mine calibrator might be already been corrupted and shouldn't be used for color proofing process. – errorist May 9 at 12:55
  • 3) I use licensed bundled software and have no intentions to buy additional one. Not till the time if I'll make my hobby a profession. If I find a chance to rent a spectrophotometer bundled with DasICColor software I definitely'll give it a try. 4) Please point where this function is because I can't find it neither in SpectraView nor in Multiprofiler bundled software. – errorist May 9 at 13:00
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    @errorist — I partly agree regarding ambient light - but what are you using? I use 5000K lights in my studio area. But also, my monitor is hooded, and I have neutral surround, that's actually what is most important — reflected colors in your field of vision. But I don't agree with using 6000 for a couple reasons, number one is that it is NOT the standard. The standard is D65, and thus all the color transforms and color management are BASED on those standards. The Standard specifies a D50 ambient and a D65 monitor. – Myndex May 10 at 6:23
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After proposed solution to re-calibrate with an automatic option for source of primary color chromaticities and doing it I achieve color gamut and curves below. A rental of spectrophotometer should improve overall quality of calibration. enter image description here enter image description here

  • Hm, that's still suspicious. I don't have first-hand experience with this particular model, but according to these tests (check the second last graph) it should be just shy of AdobeRGB green. My older 2690WUXi had a comparable amount of 'shortage' but along the red-green line rather than blue-green like yours, and the newer PA322 practically matches AdobeRGB. Also NECs typically have deeper red than the sRGB/AdobeRGB primary. Are you setting an sRGB target/mode by any chance? Can you verify if the screen OSD says 'SpectraView' mode? – Zeus May 10 at 1:17

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