Acer X27 colorimeter correction

[Lockjaw333]

I’m calibrating an Acer X27 with a colormunki display colorimeter (i1 display). What would be the correct colorimeter correction for this panel?

• PFS Phosphor WLED
• User generated correction (i1 pro + colormunki display + X27)

Is it preferable to use a user generated correction for your specific matrix? Or would PFS Phosphor be the correct selection here? They differ fairly significantly in RGB values when adjusting the white point prior to calibration- the PFS Phosphor correction calls for more Red (47-44-54), while the user generated correction has much less red (43-45-54). The 6500k corrected white points look fairly different between the two.

Thanks!

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[Vincent]

User generated correction:

a) matrix… not really portable to your i1d3, although it may work

b) CCSS. Plot it in a graph, click information button next to correction selection
-Does it look like WLED PFS? o just like generic White LED? IDNK if your display is a common sRGB display or a P3 gamer display
-3nm and looks exactly like displaycal bundled 1nm 95% P3, just “blurry” (wider & shorter peaks) due to “low” 3nm resolution, do not use it, use generic WLED PFS 1nm
-10nm and looks like WLED PFS but even blurrier, do not use it. Generic.
-3nm and have distinctive differences to WLED PFS not caused by low spectral resolution of CCSS, use custom one.

Or plot custom one, capture & share and we can take a look on them.

[Lockjaw333]

The Acer X27 is a dci-p3 wide gamut display. Its listed as a PFS phosphor with wled backlight in specifications. It also has an SRGB gamut clamp mode.

Are you saying the spectral data is viewable for user made corrections by clicking the info button next to the selection? I will have to check when I’m at my desk.

Do you think its safer to use the PFS phosphor generic correction vs user generated correction for my colorimeter?

[Lockjaw333]

How would I go about plotting the custom user generated correction? When I click the info button, it just shows a box with “Matrix” and 9 numbers below, in 3 columns of 3. I’ve attached a picture.

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[Vincent]

1st reply, if it’s a matrix and you did not make it, don’t use it.
Use Community CCSS only if they are better than generic => if they show a different backlight technology that you can’t explain by low 10nm res in i1Pro/Munki graphic arts spectrophotometers. Or for example (not your monitor) a sRGB WLED slightly different in phosphor hills than some of the generic WLED sRGB samples, using community CCSS looks like an improvement since “some” of the generic ones are a mix of several samples (like WLED sRGB, your rightest plot) and custom CCSS is just THE proper one (1).

Also don’t use that PFS but “1nm 95% P3”, Panasonic VVX… etc. Bundled with DisplayCAL. One WRGB sample and just one.

• This reply was modified 3 years, 3 months ago by Vincent.

[Lockjaw333]

So the 95% p3 panasonic correction is better than the pfs phosphor generic one? Is there a reason for that?

So in general, using a user generated ccss correction is not advised, similar to using another user’s icc profile, correct? I was under the assumption that the user generated matrix correction for your display using the same colorimeter you have would be better than using a generic correction, but I guess that may be wrong.

[Vincent]

So the 95% p3 panasonic correction is better than the pfs phosphor generic one? Is there a reason for that?

“The Acer X27 is a dci-p3 wide gamut display. “

PFS family have… sevaral flavors inside. You plot them. Use a clean one with just what you need:
-cheap inexpensive low cost gamer or multimedia displays or TVs => 95% P3 1nm WLED PFS
-P3 mac => macbook WLED PFS (100% P3 and only p3, green is different in plot)
-AdobeRGB 9x%, P3 9x% WLED PFS photo monitor => HP Z24x G2 1nm  CCSS (again, green is different providing bigger gamut than the others)

A good behaved i1d3 (=”firmware says it’s extremely close to std observer”) should have little to no change between 1st one and what you suggest. Just skiping that “chance” that it is not.
Same for RGPhosphor. That CSS has several ones, Florian extracted last sample which is U2413 GB-LED and stored it in a separate CCSS just with that. “just in case” some colorimeter reports it is not as ideal. “Less things making noise”.

Anyway, reading primaries will point which WLED PFS flavor, that 3 families is just a summary.

So in general, using a user generated ccss correction is not advised, similar to using another user’s icc profile, correct?

Not at all! Not even the same concept!
Generic have 1nm res, measured with high end devices. People who upload custom CCSS usually have low res devices (for printer profiling, 10nm), some of them do not use 3nm mode and some of them do not even measure them properly (tahy upload CCSS with SRGB emulation and so on, it should be native always). That’s the main reason.
It will be better to use a custom/user made 3nm (even 10nm)CCSS for a… WLED sRGB Dell U2415, as an example than WLED generic CCSS. First one is tailor made. Use custom there.
But a WLED PFS have very narrow spikes and at 10nm you cannot measure them, You’ll need a better device, a JETI for example and few people own them => unless is better than generic do not use custom.
If you had a JETI, measured certain WLED PFS model at 1nm native gamut and uploaded it… I will want that CCSS if I had the same display as you. It will be better than generic.

I was under the assumption that the user generated matrix correction for your display using the same colorimeter you have would be better than using a generic correction, but I guess that may be wrong.

If YOU made that matrix with a device that you call REFERNCE, yes, use matrix, taht way your REFERENCE device and corrected colorimetr will match. But you did not make them.

On the other hand CCSS generic or CCSS custom  are “portable” between i1d3… matrices are generated on the fly with firmware data (YOUR device) and CCSS data. That the reason i1d3 are cool and Spyders X are not. They do not have such feature. You can use other people CCSS as long as they are better tahn generic because thay are portable.
Thats the reason i1d3 was a game changer: non fading filters, software upgradeability with spectral corrections for newer backlights without taylor made matrix corrections for YOUR colorimeter and YOUR display (and only valid for them). You just need that CCSS backlight is the same as your display. Individual colorimeter differences are taking into calculations on device startup (firmware data + CCSS => custom matrix for YOUR colorimeter)

Summary:
Matrix = make a colorimeter measure like some other device for a particular display.
CCSS = portable correction between i1d3 and between displays with the same or very close spectral power distribution (CCSS plot)

• This reply was modified 3 years, 3 months ago by Vincent.

[Vincent]

Let’s summarize it: The technological requirements for making a good CCSS correction for WLED PFS displays are higher. That’s the reason to “check” first what is inside custom CCSS made by others, the PLOT icon:
-make sure it’s 3nm (may be not need for WLED sRGB)
-make sure native gamut (no red or green channels as linear combination of others, like for example generic CCSS channels)
-make sure it is not just a downgraded version (worse resolution, same backlight) from a generic CCSS

[Lockjaw333]

Thanks so much for the explanations!

It seems the user generated corrections were made using my monitor, the same colorimeter (colormunki display), and an i1 pro 2 spectrophotometer. I have no way of viewing the spectral graph for them, but it says they were generated with 3nm resolution. Would you consider the i1 pro 2 a good enough reference device, or is a higher priced reference device like you mentioned necessary?

I just find it odd that the custom corrections all call for a cooler white point when adjusting to 6500k (I tried a few that are available), while the generic p3 corrections give a warmer white point. My eyes can adjust to either white point within a few minutes,  so I’m not sure which one is the “correct” one. I would say the user generated CCSS white point looks more correct to my eye, as I have D65 lighting at my desk and it appears closer to that than the pfs phosphor generic corrections, where the white looks to be slightly too red.

I am obsessing over what is a small difference in reality, but I am more interested in why the difference is there in the first place. Your replies so far have been informative and interesting.

[Vincent]

. . .

-Do not use matrix unless you made them (at 3nm if possible)

-i1Pro2 is not a reference device for measureing WLED PFS. Use CCSSs made by it only if they are better than generic (if they store something different)

[Lockjaw333]

I have an update to this situation. I’ve figured out through some digging that the Acer X27 actually employs a quantum dot solution to achieve its wide gamut. Its a FALD display with 384 zones.

In that case, what would  be the correct colorimeter correction? Note that there are only Matrix corrections available in the online database, no spectral corrections for this display.

Should I choose the Quantum Dot option that is available (Samsung QLED Q9)? From what I understand, quantum dot generally has 3 very distinct peaks for R, G and B and all 3 are at similar intensities. Its quite different than a pfs phosphor spectral distribution. If none of the available corrections are a match, am I better off using “None”?

The reason I’m hung up on this is because depending on what correction I choose, I get extremely different results for RGB balance controls, which produces very different looking whites.

[Vincent]

Use Samsung, unless your 255 native green uncorrected is close to AdobeRGB instead of P3 green. In that case a cleaned SW2700PT native gamut CCSS (search in forum) or some gamer Asus in colorimeter database (I do not remember model, some 27″ or 3x” PG model)

If you have to guess:

Suggestions for correction (XP-Pen Artist 15.6 Pro)

If choose no correction, set white visually.

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