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U2413, Cannot get 99% adobeRGB coverage?
Hello,
I got a (refurbished) replacement monitor from Dell after contacting them regarding low contrast ratio issue that yumichan figured out from my earlier post: http://en.community.dell.com/support-forums/peripherals/f/3529/t/19652479
After connecting the replacement unit, I ran a few calibration (Native and adobeRGB) with i1Display Pro + DCCS and verification dispcalGUI.
I did the same thing as before:
1. Factory reset monitor
2. Disassociated all ICC profiles in Windows (I run Windows 7)
3. Calibrated with DCCS 1.5.3 (newer version couldn't "find" my display)
a. For "native" calibration, I manually entered RGB x,y taken from EDID generated with dispcalGUI; WP 0.313, 0.329; 120 cd/m; Bradford, Version 2, Table based; Large patch set
b. For adobeRGB, I simply selected the preset from drop down menu; and the rest was same as "native" calibration
4. Verified results with dispcalGUI 3.0.4.3 (latest version)
a. RG_Phosphor for correction; verify_extended.ti1 testchart
d. I made sure the ICC profile was set as default in Windows; "Current" was chosen under Settings in dispcalGUI
The results:
The contrast seem okay, a lot better than previous unit and passed all recommended tolerance. Then I ran a "Profile Only" in dispcalGUI for the "Native" calibration using these settings:
This is what I got:
When I did the same thing with the previous U2413 unit (the one with low contrast than usual), I would get 100% and 99% gamut coverage for sRGB and adobeRGB respectively.
I repeating the steps a few times and still receive similar results. According to a post by yumichan I read before, these Dells shouldn't have gamut coverage issue. What am I missing here?
Please help. Thank you.
yumichan
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October 7th, 2015 02:00
Color managed performance needs two things:
1-Gamut coverage. Gamut "edges" will set a minimum dE for each colorspace to simulate. Usually for wide gamuts most of colorspace edges to simulate are not printable so it does not matter. For example AdobeRGB green is not printable, but cyan should be printable.
2-Profile accuracy. It means how good profile is capturing actual monitor behaviour.
That second one "could" be improved with a Profile only with DispcalGUI. Read its documentation for "profile only" (without calibrating) tasks. Even a DCCS "table profile" 400 patches should be more accurate than a DCCS matrix one.
yumichan
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October 2nd, 2015 00:00
1- Results between 95-99% are OK. 99% AdobeRGB intersection is for the panel in its native state.
2- Do not think in % terms because it is useless. Run a comparison between AdobeRGB and your profiles, there should (WILL) be a very small dE between profile green 0,255,0 and AdobeRGB green, so it's fine. Your eyes do not see % coverages but color differences (deltaE2000)
Your reports are very good and DCCS gives you a very good neutral grey (better than my unit, but my AMD GPU fix that issue) and expected "after DCCS" contrast, so it's all OK
t6ho
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October 2nd, 2015 11:00
yumichan, when you say run a comparison, is there a report on dispcalGUI to do this with?
yumichan
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October 5th, 2015 01:00
Yes, validate profile against a reference ("measurement report"). Two ways:
-validate calibration against AdobeRGB profile, not useful since if you need AdobeRGB support you need color managed app... so it's useless unless you need to validate grey ramp calibration in a fast way.
-validate profile simulating AdobeRGB, that means how that profile will perform in color managed apps showing AdobeRGB images.
Be careful with gamma simulation options, a true 2.2 power gamma means infinite contrast (0cd/m2 brightness in black). Read DispcalGUI documentation.
t6ho
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October 5th, 2015 14:00
This is what I did:
And this is what I got:
https://www.dropbox.com/s/97wzjzu17rnjdv7/Measurement%20Report%203.0.4.3%20%E2%80%94%20DELL%20U2413%20%40%200%2C%200%2C%201920x1200%20%E2%80%94%202015-10-05%2016-04.html?dl=0
Does it seem right, yumichan?
yumichan
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October 6th, 2015 01:00
That setup with "use smilation profile as target" is "CASE 1" in my previous post. Without that checkbox is "CASE 2", which is the color managed approach.
You used to check against a true 2.2 power gamma that your monitor CANNOT do, because it has not infinite contrast. I warned you prevoiusly against doing that... Select unmodified.
t6ho
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October 6th, 2015 12:00
Okay.
This is what I did and got:
https://www.dropbox.com/s/ttnh2itorexohv4/Measurement%20Report%203.0.4.3%20%E2%80%94%20DELL%20U2413%20%40%200%2C%200%2C%201920x1200%20%E2%80%94%202015-10-06%2013-42.html?dl=0
All seems good now, right?
t6ho
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October 6th, 2015 13:00
How could the results be improved? Via dispcalGUI calibration?
yumichan
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October 6th, 2015 13:00
Could be better but yes.