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I have a Thinkpad Z16 with OLED display. According to specs and reviews it has high colour coverage and high colour accuracy due to factory calibration. Indeed, using my i1Display Pro the colours barely changed after calibration with both DisplayCal and Calibrite’s software. However to my eyes there is a noticeable green cast compared to every other display I own, including the Macbook Pro M1 and a calibrated, expensive monitor.
I wonder if the touchscreen layer on this OLED display, which adds a tiny grid pattern to the screen, has some effect on my perception of the colour or the calibrator’s ability to work properly?
Does anyone know what I could do to get a good result?
Calibrite Display Pro HL on Amazon
Disclosure: As an Amazon Associate I earn from qualifying purchases.Please go to the “Verification” tab, choose the XXXL verification testchart (the very last one on the list) and create a measurement report.
I’ve attached the report. I generated it after doing a calibration (with both the display and colorimeter warmed up over 30 minutes). The mode I chose was LCD and Correction was RGB OLED family (Sony PVM, Samsung Galaxy, Lenovo). White drift compensation was ticked and calibration speed was set to Medium.
I also have a laptop with an OLED display.
I had the same problem with crushed reds (patches n.on. 43, 44 and 45) that you have, though my display had no green overcast.
For starters, you need the latest test version or Argyll CMS, which I’ve been testing for the last few weeks).
To get it, contact Greame Gill, the developer of Argyll: http://argyllcms.com/gwg/
He’s very nice and helpful.
Once you have it, use the following calibration settings:
- Calibration speed: “Low”
- Black and white point compensation: active
- Luminance: 100 cd/m2
- White point: 6500K
- Testchart: “Very large testchart for LUT profiles” (4954 patches)
- Profile type: “XYZ LUT + Matrix”
In the measurement window set the display’s brightness to a level slightly above the target value – like 105 cd/m2 – to compensate for Argyll’s tendency to lower the display’s brightness level by a few nits.
The calibration process will take about four hours, but the results might be very much worth it. That’s exactly how I got the best results so far.
Don’t use auto-optimized patchsets because they produce worse results.
Thanks very much for those details! I actually came across an interesting excerpt from an article last night after realising the Pixel 7 Pro display was a very close match to the Thinkpad OLED.
The fact of the matter is that current methods of color measurement don’t provide a definitive assessment for color matching. As it turns out, the difference in spectral distributions between OLEDs and LCDs creates a disagreement in the appearance of their white points. More precisely, the color of white on OLEDs will typically appear yellowish-green compared to an LCD display that measures identically. This is known as metameric failure, and it’s been widely acknowledged to occur with wide-gamut displays such as OLEDs. The standard illuminants (e.g. D65) have been defined with spectral distributions that match closer to that of an LCD, which are now used as reference. For this reason, an offset towards magenta is needed for the white point of OLEDs to perceptually match the two display technologies.
Source: https://www.xda-developers.com/google-pixel-7-pro-display-review/
I then went on to compare several more displays and have concluded that all the OLED screens have similar characteristics where they look more yellowish/greenish whilst the LCDs looked more magenta. So it seems that in fact the Thinkpad OLED is actually calibrated correctly after all. In fact the display on my iPhone 13 Pro looked closer to the Thinkpad than to the Macbook Pro M1. (I am not rich BTW. I just happened to have all these devices as im thinking of switching systems).
I then went on to compare several more displays and have concluded that all the OLED screens have similar characteristics where they look more yellowish/greenish whilst the LCDs looked more magenta.
No, it’s your eyes. That’s what observer metameric failure means.
-we (may) have a potential issue in CIE 1931 2 degree not matching a “mean” of human observers (try to use CIE 2012 2 degree and see if it improves, HTML report will aim to CIE 1931 so if you do that do not care about “measured vs assumed whitepoint”)
-we have an statistical issue due to std ovservers being a “mean” of human observers, hence created from data that has some standard deviation / variance. This causes that spectral power distribution with narrow peaks or located at certain wavelengths result in higher variance to color coordinates “measured” by the visal system of SOME humans which are statistical outliers to that computed mean we label as std observer
So that statement you quote from that web is false:
The fact of the matter is that current methods of color measurement don’t provide a definitive assessment for color matching.
(you can’t: even with lab grade equipment you can’t remove the statistical distance from a mean of human observers, although we can try to get a better “mean”, a better std observer)
And the rest of the text is slightly innacurate because it fails in the root concept.
So it seems that in fact the Thinkpad OLED is actually calibrated correctly after all.
No.. or yes… or maybe. Instead of looking at the report take a look on VCGT grey calibration data. Report shows 9x% unique grey levels so there is a VCGT modifiying grey/white.
I also have a laptop with an OLED display.
I had the same problem with crushed reds (patches n.on. 43, 44 and 45) that you have, though my display had no green overcast.
For starters, you need the latest test version or Argyll CMS, which I’ve been testing for the last few weeks).
To get it, contact Greame Gill, the developer of Argyll: http://argyllcms.com/gwg/
He’s very nice and helpful.
Once you have it, use the following calibration settings:
- Calibration speed: “Low”
- Black and white point compensation: active
- Luminance: 100 cd/m2
- White point: 6500K
- Testchart: “Very large testchart for LUT profiles” (4954 patches)
- Profile type: “XYZ LUT + Matrix”
If he is worried about whitepoint color cast, maybe fast and matrix will be a better choice to evaluate the effects of certain CCSS or other observsers than CIE 1931 2degree.
I mean, get white first in this trial error approach.
Then use your setup (XYZLUT + slow to calculate VCGT grey correction more accurately)Did you ever successfully calibrate? I know it’s only tangentially related but I’m also trying to calibrate an OLED–a QD-OLED specifically, the MSI 321URX. Have tried countless approaches at this point, in a variety of software. My issue is a bit different from yours though. Tracking the target gamma curve and blue hues/saturation is generally quite good, but green and red (which happen to be the hues with unique spectral behavior on the QD OLED panel type) are consistently undersaturated post-calibration, compared to reference.
