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I got a Dell U2415 and i1 Display Pro.
I made a recalibration recently and noticed that I white seems to get clipped.
I am using Office & Web (D65, Gamma 2.2), the brightness I calibrated to 120 cd/m2.
Correction: Spectral: LCD White LED family (AC, LG, Samsung)
The monitor has contrast set to 75, which is the default.I am looking at these images (attached)
taken from http://www.lagom.nl/lcd-test/black.php and http://www.lagom.nl/lcd-test/white.php
And in that state I can see up to 253, I can’t seem to see 254.
After calibration it makes things brighter, so I think 253 is is visible but just barely, 254 is probably gone if it was even there to begin with.
Is my eyes playing tricks on me?
Can the calibrated profile show if the whites/contrast are getting clipped?Calibrite Display Pro HL on Amazon
Disclosure: As an Amazon Associate I earn from qualifying purchases.It is probably your eyes. BTW a screenshot looks differnet on a uncalibrated monitor than one that is. The webpage and yours look the same to me. Calman brightness/contrast shows better 254. AVS HD 709 has brightness/contrast patterns too. 254 is visible there too. I think its the webpage and the tv. I had a tv and different monitors and could see 254 different on each one. 254 being very close to 255 is a good thing. It gives more room for blacks and more contrast. It is hard read to puzzles though. A profile can show if its TRC is clipped. Profile Loader has profile info under profile associations.
It’s not a screenshot, I just uploaded the image from that webpage, as the site is in http not https, to prevent linking issues:)
What’s TRC?
I attached the profile info.
I got a Dell U2415 and i1 Display Pro.
I made a recalibration recently and noticed that I white seems to get clipped.
I am using Office & Web (D65, Gamma 2.2), the brightness I calibrated to 120 cd/m2.
Correction: Spectral: LCD White LED family (AC, LG, Samsung)
The monitor has contrast set to 75, which is the default.I am looking at these images (attached)
taken from http://www.lagom.nl/lcd-test/black.php and http://www.lagom.nl/lcd-test/white.php
Need to be viewed in MS Paint, otherwise that test is pointless.
And in that state I can see up to 253, I can’t seem to see 254.
After calibration it makes things brighter, so I think 253 is is visible but just barely, 254 is probably gone if it was even there to begin with.
Is my eyes playing tricks on me?
Can the calibrated profile show if the whites/contrast are getting clipped?Your display is 6bit+FRC and you are applying a 16bit VCGT grey calibration that depening on your RGB gain+offset settings in monitor may need an additional correction near 255 white to get desired xy white (so 255 IN won’t be 65535 OUT) …and depending on your video card that 16bit VCGT may bet clipped to 8bit even if you use DisplayCAL LUT loader, like some intels and nvidias.
You may see the effects of rounding errors and some of them are at hardware/driver level which DIsplayCAL is not responsible for.
After getting your display to D65 or whatever you use on HW (RGB gain +offset on display OSD) try to set white point “as measured” and see if this improves.
Also lower calibration speed, so ArgyllCMS will take 96 point / 256 actual measurements to compute VCGT (depending on other things if display grey is near perfect uncalibrated, you may try the opposite, the very fast setting with 12 point)
Also use single curve + matrix with black point compensation as profile type (may need to set settings to advanced to see it. This should be the cleanest path with actual grey calibration and color management supportEven to be sure no clipping measure white brightness and target a little below it. The nits between 255 and 254 is little at low brightness 100nits SDR. 2 nits round up and 3 nits round down. TRC is tone response curve. I recommend slow speed calibration and measuring nits before calinbration and set calibration to below its standard. A little clipping at 254 is not a problem on most content. I recommend getting contrast set before measureing and doing it by eyes. Use the contrast control. Go up till white gets no brighter and then down till it goes down at 254. It might not because of rounding errors. Try 8 bit or 10 bit bit depth in displaycal loader. A 6bit plus frc is 8 bit visually hopefully.
I viewed the image in MS Paint with same results.
After getting your display to D65 or whatever you use on HW (RGB gain +offset on display OSD) try to set white point “as measured” and see if this improves.
So basically start an D65 calibration, do the first step till RGB and Brightness are are in the middle, then cancel and redo with white point “as measured”, is that correct?
Also lower calibration speed, so ArgyllCMS will take 96 point / 256 actual measurements to compute VCGT (depending on other things if display grey is near perfect uncalibrated, you may try the opposite, the very fast setting with 12 point)
Is “96 point / 256” the medium calibration speed?
Use the contrast control. Go up till white gets no brighter and then down till it goes down at 254.
Going from 75 to 74 makes it visible, but it’s a huge difference overall, white becomes “pinkish”.
For fun I tried lowering Contrast in Nvidia from 100 (default) to 99 also makes it visible, without having the same huge impact.
Open HCFR and measure 250-255. Clipping will be easy to recognize.
Not sure how to do that measurement, I installed it but can’t say I understand it too well, could you tell me the steps if it’s not too much to ask?
If its pink it was crushing. It was overcompensated in Red. Lower contrast to 74 and adjust white balance red at 95%. Going by meter and not eyes is the way to go. You could should a full screen of 254 and it will turn white probably to your eyes but it will not be D65. High brightness is critical to eyes and eyes sensitive to high brightness relative in the 100 nits range.
I prefer another way but a lot more complicated but looks better. I do manually but do not adjust red since it is the one crushing. Lowering it wont hurt but a little crush is ok. I actually calibrated red and green to match each other and kept blue at its defaults in 20 point and white balance gain. Blue was high and could not raise red to match it. Then I did brought blue down to match red and green but then red went up. A lower blue means higher red in electronics it has more room to make red. Going down in red and blue is better than going down in green. HCFR gets it perfect. Then just make a displaycal profile for use in color aware apps. I do keep my contrast at default it looks better. I adjust 95 and 100 to get the pink tint out. Displaycal will do that too. It does it especaly if your target white is lower than the screen white nits. HCFR tells the exact amount.
It is pink because the 100 white is D65 but 99% is close to 100 in eyes but is the same in red as 100. It is tough to get pink out. Displaycal even get the red out in my dark greys since it raised blue over there and blends the blue from black to white by the amount it knows and is visually better than manual.
I’ve seen Dell whites turn “pinkish” before. The solution was to lower contrast until it went away.
I forgot the medium speed is not 96 points of white checked. The High setting for quality is what you need. The low and extra low are for testing faster.
I viewed the image in MS Paint with same results.
After getting your display to D65 or whatever you use on HW (RGB gain +offset on display OSD) try to set white point “as measured” and see if this improves.
So basically start an D65 calibration, do the first step till RGB and Brightness are are in the middle, then cancel and redo with white point “as measured”, is that correct?
Yes, it should be the “clearest” upper end VCGT if greys have the same color as white. As DaniJ pointed you can measure color tint error in 250-255
Also lower calibration speed, so ArgyllCMS will take 96 point / 256 actual measurements to compute VCGT (depending on other things if display grey is near perfect uncalibrated, you may try the opposite, the very fast setting with 12 point)
Is “96 point / 256” the medium calibration speed?
“Slow”, It takes 4 iterartions 12-24-48-46, about 15-20min depending on black level.
