DisplayCal Vs X-Rite Software

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  • #14260

    CosmicSpace
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    keeping in mind this is a profile self check, and not an additional set of measurements where display and instrument drift could have played a role.

    The profiles were newly created today. How would I minimize drift?

    It’s not an issue. Look at delta E and delta L. Gamma is just informational.

    I was expecting a 2.2 gamma all the way across. So as long as delta E and delta L is close to 0, then it doesn’t matter if nominal and measured gamma shows 2.05 at 95% level or 2.3 at 85%?

    I had calibration showed in these ranges before but still passed delta E recommended.

    #14261

    Florian Höch
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    The profiles were newly created today. How would I minimize drift?

    I was not pointing out that drift was an issue, only that the profile created by the ColorMunki software didn’t seem to be particularly accurate (as you’ve discovered yourself, too). As for the reasons for that, I’m not sure – could be something specific to the ColorMunki software itself. The profile has probably been created using a “best fit” matrix approach internally by the software, and the measurements consisted of more than just grayscale + primaries. A “best fit” matrix tries to minimize delta E across the range for all measured colors, but for displays with nonlinearities I’ve seen this approach produce less than ideal results at times (contrary to what one would expect from such an approach, which I find interesting). Consequently, DisplayCAL by default only measures grayscale + primaries for matrix profiles, and while this is a more simplistic approach, it seems to consistently produce better matrix-based profiles in most cases.

    Speaking of display drift and measuring conditions, the best practices are usually to let the display warm up for some time, ensuring stable environmental conditions, not letting direct light shine on the display during measurements, and making sure the instrument sits flat on the screen surface so no stray ambient light can enter from the sides. In terms of MacBooks, there’s also the translucent Apple logo on the back through which light could enter and influence measurements. A piece of black cardboard taped or otherwise firmly attached over the region of the logo helps with that should it become an issue.

    I was expecting a 2.2 gamma all the way across. So as long as delta E and delta L is close to 0, then it doesn’t matter if nominal and measured gamma shows 2.05 at 95% level or 2.3 at 85%?

    Gamma is not a meaningful perceptual metric, because even tiny changes in brightness near the extremes (i.e. near black and near white) can cause changes in gamma that have not necessarily a bearing on the visual appearance. Thus, a perceptual metric (like delta L) is better suited to the task of evaluating display performance.

    #14298

    CosmicSpace
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    Consequently, DisplayCAL by default only measures grayscale + primaries for matrix profiles, and while this is a more simplistic approach, it seems to consistently produce better matrix-based profiles in most cases.

    I created a 3DLUT from previous measurement data, I was 1553 patches measured, to use with Kodi but it has a reddish tint.

    MadVR isn’t supported on Mac, so under “Display”, I switched from “madVR” to my laptop’s primary display “MacBookPro8,1 @ 0, 0, 1280×800”, I ran a verification and got good results.

    But in Kodi, it has the red tint.

    • This reply was modified 5 years, 5 months ago by CosmicSpace.
    • This reply was modified 5 years, 5 months ago by CosmicSpace.
    • This reply was modified 5 years, 5 months ago by CosmicSpace.
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    #14303

    CosmicSpace
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    Also using AVS 709 test patterns there is a pinkish tint on black and white clipping test patterns. Switching to limited range seems to fix the tint on the patterns but my laptop is full range and it leaves a grayish bar from top to bottom instead of a black bar.

    Adjusting brightness makes sure black levels are displayed correctly in video but the area outside the video still has a grayish bar. But the reddish tint stays on the whole picture no matter I use full or limited range.

    I don’t know if this is a problem with the 3DLUT since Mac doesn’t support madVR. And I do measurements in displaycal rather than in madVR.

    • This reply was modified 5 years, 5 months ago by CosmicSpace.
    • This reply was modified 5 years, 5 months ago by CosmicSpace.
    • This reply was modified 5 years, 5 months ago by CosmicSpace.
    #14316

    Florian Höch
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    But in Kodi, it has the red tint.

    Does Kodi for Mac work correctly? It should use only the 3D LUT, and not let the system color manage its output again. Does it do that? An easy way to test is to create the 3D LUT without calibration (vcgt) applied, although that will only tell you if the calibration is affecting Kodi output when using the 3D LUT, not if the system color management affects its output as well.

    #14323

    CosmicSpace
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    But in Kodi, it has the red tint.

    Does Kodi for Mac work correctly? It should use only the 3D LUT, and not let the system color manage its output again. Does it do that? An easy way to test is to create the 3D LUT without calibration (vcgt) applied

    That fixed my problem. I disabled VCTG and no more reddish tint.

     although that will only tell you if the calibration is affecting Kodi output when using the 3D LUT, not if the system color management affects its output as well.

    To test this can I use the bad profile created by X-Rites software to see if the system color management is affecting it? Switch back and forth to see a difference?

    Does my profile I created in displaycal that I used as the source to create the 3dlut need to be selected in system preferences to match, or can I use a different profile and 3d lut won’t be affected? Is it independent of it?

    #14324

    Florian Höch
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    You can assign the AdobeRGB profile in system preferences and if colors get less saturated in Kodi output, you know that it is being double color managed.

    #14343

    CosmicSpace
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    You can assign the AdobeRGB profile in system preferences and if colors get less saturated in Kodi output, you know that it is being double color managed.

    Colors got less saturated, using X-rites linear profile downloaded here. Calibration is being applied twice.

    How do I go about this? Do I just stick with 3Dluts created with VCTG unchecked?  And have my icc profile enabled (the one I used to make the 3Dlut) in macs system preference, then pick the 3DLut in kodi.

    Or, do I create a 3Dlut with VCTG enabled, enable x-rites linear profile in macs system preference, and pick my 3dlut in kodi.

    Which will give better results. Or should I do something different?

    • This reply was modified 5 years, 4 months ago by CosmicSpace.
    #14345

    Florian Höch
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    If you don’t care about correct macOS color, assign sRGB in system preferences, keep the 3D LUT (this time, with vcgt).

    #14347

    CosmicSpace
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    If you don’t care about correct macOS color, assign sRGB in system preferences, keep the 3D LUT (this time, with vcgt).

    This profile right? sRGB IEC61966-2.1

    #14348

    CosmicSpace
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    If I want to keep macOS color managed then I create a 3dlut with VCTG disabled. Use that same profile I used to create the 3dLut in mac system preference. Then load up Kodi with that 3dlut is this correct?

    #14349

    Florian Höch
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    This profile right? sRGB IEC61966-2.1

    Yes (should be the only sRGB profile there). In theory, this should result in a ‘null’ transform (macOS color management effectively off).

    #14350

    Florian Höch
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    If I want to keep macOS color managed then I create a 3dlut with VCTG disabled.

    No, in that case, assign the correct profile in system preferences and use the standalone 3D LUT maker to create a Rec. 709 (source profile) with whichever tone response you want to sRGB (destination profile) 3D LUT.

    EDIT: All this assuming I’m understanding correctly from afar how Kodi is affected by macOS color management. With what I just said you can test this, when disabling the Rec. 709 to sRGB 3D LUT in Kodi, you should only see a relatively subtle tone curve difference, with colors mainly unchanged.

    • This reply was modified 5 years, 4 months ago by Florian Höch.
    #14353

    CosmicSpace
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    If I want to keep macOS color managed then I create a 3dlut with VCTG disabled.

    No, in that case, assign the correct profile in system preferences and use the standalone 3D LUT maker to create a Rec. 709 (source profile) with whichever tone response you want to sRGB (destination profile) 3D LUT.

    EDIT: All this assuming I’m understanding correctly from afar how Kodi is affected by macOS color management. With what I just said you can test this, when disabling the Rec. 709 to sRGB 3D LUT in Kodi, you should only see a relatively subtle tone curve difference, with colors mainly unchanged.

    3D LUT maker, source profile=rec. 709, tone curve=2.2, Destination Profile=RGB IEC61966-2.1. I named it “Rec.709 2.2 3D Lut” Then create madVR 3D Lut.

    Then pick my DisplayCal ICC profile in Mac system settings. And load up my just created 3D LUT. Did I do this right? Colors changed, they became more saturated.

    Switching back and forth from the sRGB profile in system settings with my created 3D Lut with VCTG enabled.

    To my created DisplayCal profile with my newly created “Rec.709 2.2 3D Lut”, and I see a difference in color. More saturated.

    #14364

    Florian Höch
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    Switching back and forth from the sRGB profile in system settings with my created 3D Lut with VCTG enabled.

    No, do not switch the display profile, leave it at the correct one, not sRGB.

    Toggle the 3D LUT in Kodi – you should only observe a tone curve change (lightness).

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