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Hello. I’m calibrating my new monitor BenQ PD2500Q.
I had calibrated it using the preset “office and web” but using a curves + matrix type profile. instead of XYZ lut + mratix
at the end of the process, I find the monitor have a slight magenta cast in color management applications compared to my old monitor dell u2515h.
SO I tried to redo the calibration but this time using “as measured” for white level and white point, this because I have read this in an article on a website:“When you set a colour temperature target you are only defining the blue to yellow colour axis and not the green to magenta tint. So sometimes forcing a screen to 6500K, for example, gives it a slightly green or magenta tint. If this happens then try selecting native white point in your calibration software. This will leave the white point of your screen alone and should get rid of the cast”.
in fact, after installing the new profile, I made a verification report that gave me a good result. so I compared a photo on my two monitors and it looked very similar,now the magenta cast has almost completely disappeared.
Then I restarted my PC, and noticed that the magenta cast was present again, more slight but visible.
so after a few minutes I made a new measurement report, this still looks like a good report, at least I think.
but this time with Evaluation criteria “RGB + gray balance, and and activating the option “Evaluate gray balance through calibration only”. RGB gray balance (>= 1% luminance) combined Δa*00 and Δb*00 range is NOT OK, Nominal tolerance exceeded.
can this have anything to do with the magenta cast problem?Thanks in advance.
VGA: GTX 1070 ti. 430.86 Studio drivers
SO: Windows 10 1903 with last update
Colorimeter i1 Display proCalibrite Display Pro HL on Amazon
Disclosure: As an Amazon Associate I earn from qualifying purchases.-Win10 1903 is caussing some issues in calibration, even altering linear GPU LUT ramps in HW calibration profiles, so if you see strange things regarding grey grange thay may be caused by Windows itself.
-GPU LUT contents truncation (by HW, driver or OS) may cause a cast if LUT contents at 255 entry are not exactly that value. It is not your situation in attached profile.
-Lack of color uniformity on 2 screens may difficult visual matching. When you measure at the center i1d3 may see a match and be an actual match. This is not colorimeter o softwarwe fault.
-Once Windows solve all/some of these issues if you want to match 2 screens using i1d3 and bundled CCSS corrections, try to be close to your calibration target with i1d3 measurements (RGB bars in DIsplayCAL), then modify RGB/gain offset until you get a visual match setting as measured/native to white point so DisplayCAL do not tries to modify it.
Thank you Vincent.
So if I understand correctly the problem could is that the two monitors have a different visual color temperature even though both are calibrated in D65. Did I get it right? but one thing is not clear to me, Should color management programs compensate for the differences? I opened the same image on both monitors in irfanview image viewer that is color management. Compared side by side, On the benq monitor the image appears slightly magenta compared to the dell monitor.Thank you Vincent.
So if I understand correctly the problem could is that the two monitors have a different visual color temperature even though both are calibrated in D65. Did I get it right?No. I did not say this, not even close.
I said color uniformity could be bad across screen, so it could be your monitos fault. There is a visual match in the center (where measured), but overall screen has a cast. There is no way to correct that with current GPU hardware for calibration. This is one possibility.
Another one is that spectral power distribution of those 2 WLED sRGB screen is not “exactly” equal that bundled sample/reference for WLED sRGB screens. If you do not own a “true reference” measurement device to overcome that issue and correct your colorimeter measurements, use visual match approach once you have D65 (numeric, measured) in your screens.
Another one could be GPU an its driver or HW limitations.
I opened the same image on both monitors in irfanview image viewer that is color management. Compared side by side, On the benq monitor the image appears slightly magenta compared to the dell monitor.
Known apps with “good enough” color management for “everyday use”:
Asobe suite, Firefox (full color management, but limited precision), old windows photo viewer (only matrix profiles)… etc, there are more. IDNK what Infranview does.
