profiling restricted to Rec709??

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  • #30343

    user3434343
    Participant
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    Hi,

    there is an interesting phenomenon which I don’t clearly understand.

    I did first a precal profiling of the display of Lenovo P17 (4k, DolbyVision, “color calibrated”). (attachement 1, Screenshot 101411.gif). The profile was measured with colourspace software.  The surrounding borders are the AdobeRGB colourspace and it can be seen that it is nearly 100% covering precal.

    Then I calibrated/profiled with DisplayCal. XYZLUT+Matrix. As I understood this process is just profiling this individual monitor and will not limit the profile ICC to any special colourspace. After profiling, the ICC profile was activated.  See the results in the second attachement (Farbumfang..png) and the printout below.

    All looks good so far and I profiles again postcal the display with colourspace again, same way as precal, just lesser points. The interesting result you can see in the third attachement:

    As before, the white borders are the AdobeRGB colourspace which is nearly identical with the native one from the display. You can see that after calibration (using the same pattern generator and patches) all are now in a much smaller area within this native garmut and interestingly, the inner rectangle reflect extremely well the Rec709 colourspace (which was never selected and not wanted).

    What I would have expected also in postcal is to see again all points within the AdobeRGB colourspace, just with less errors. But is it normal that display automatically “shortens” the native colourspace to be Rec709? Again, the colourspace software for pre and postcal are running on a different computer, all patches are exactly the same, nothing wrong here.

    Or how do need to configure displaycal (see our profile below) to end up with a best calibrated/profile ICC for this monitor without restricting to a smaller garmut then the native one?

    very best, thanks so much!

    displaycal: profile:

    Größe  1565784 Bytes (1529.09 KiB)

    Bevorzugtes CMM        0x6172676C ‘argl’ ArgyllCMS

    ICC-Version       2.2

    Profilklasse       Anzeigegeräteprofil

    Farbmodell       RGB

    Bezugsfarbraum (PCS)  XYZ

    Erstellt 2021-05-27 01:15:04

    Plattform          Microsoft

    Ist eingebettet Nein

    Kann unabhängig verwendet werden    Ja

    Gerät

    Hersteller      0x0000AE30 Lenovo Group Limited

    Modell          0x00004125

    Medien-Attribute      Reflective, Glossy, Positive, Color

    Standard-Farbübertragung        Wahrnehmung

    PCS-Leuchtmittel XYZ   96.42 100.00  82.49 (xy 0.3457 0.3585, CCT 5000K)

    Ersteller            0x6172676C ‘argl’ ArgyllCMS

    Prüfsumme             0x4270ED1AD888B2657DB56F03409F82C2

    Prüfsumme OK          Ja

    Beschreibung (ASCII)    NE173QUM-N42 #1 2021-05-26 23-58 0.3127x 0.329y S

    XYZLUT+MTX

    Urheberrecht   No copyright. Created with DisplayCAL 3.8.9.3 and

    ArgyllCMS 2.1.2

    Gerätehersteller (ASCII)             Lenovo Group Limited

    Gerätemodell (ASCII)    NE173QUM-N42

    Helligkeit          347.06 cd/m²

    Medien-Weißpunkt

    Ist Leuchtmittel         Ja

    Leuchtmittel-Bezug XYZ         95.32 100.00 107.32 (xy 0.3150 0.3304)

    Leuchtmittel-Bezug CCT         6372K

    ΔE 2000 zu Tageslicht-Farbort         0.74

    ΔE 2000 zu Schwarzkörper-Farbort              4.05

    Medien-Schwarzpunkt

    Leuchtmittel-Bezug XYZ         0.1083 0.1144 0.1221 (xy 0.3142 0.3319)

    Leuchtmittel-Bezug CCT         6405K

    ΔE 2000 zu Tageslicht-Farbort         1.05

    ΔE 2000 zu Schwarzkörper-Farbort              5.49

    Farbmittel (PCS-Bezug)

    Rot XYZ         61.53  31.45   1.54 (xy 0.6510 0.3327)

    Grün XYZ       20.32  62.95   6.44 (xy 0.2265 0.7017)

    Blau XYZ        14.31   5.36  74.39 (xy 0.1521 0.0570)

    Grafikkarten-Gammatabelle

    Bittiefe          16

    Kanäle           3

    Anzahl Werte pro Kanal         256

    Kanal 1 Gamma bei 50% Stimulus      1.00

    Kanal 1 Minimum      0.0000%

    Kanal 1 Maximum     100.00%

    Kanal 1 eindeutige Tonwerte 256 @ 8 Bit

    Kanal 1 ist linear        Ja

    Kanal 2 Gamma bei 50% Stimulus      1.00

    Kanal 2 Minimum      0.0000%

    Kanal 2 Maximum     100.00%

    Kanal 2 eindeutige Tonwerte 256 @ 8 Bit

    Kanal 2 ist linear        Ja

    Kanal 3 Gamma bei 50% Stimulus      1.00

    Kanal 3 Minimum      0.0000%

    Kanal 3 Maximum     100.00%

    Kanal 3 eindeutige Tonwerte 256 @ 8 Bit

    Kanal 3 ist linear        Ja

    Gerät zu PCS: Anpassungsart 0

    Matrix           1.0000 0.0000 0.0000

    0.0000 1.0000 0.0000

    0.0000 0.0000 1.0000

    Eingabe-Tabelle

    Kanäle       3

    Anzahl Werte pro Kanal     2048

    Farbwerte-Tabelle

    Raster-Schritte       33

    Einträge    35937

    Ausgabe-Tabelle

    Kanäle       3

    Anzahl Werte pro Kanal     2048

    PCS zu Gerät: Anpassungsart 0

    Matrix           3.9250 -1.2213 -0.6827

    -1.9575 3.8322 0.0668

    0.0574 -0.2813 2.6985

    Eingabe-Tabelle

    Kanäle       3

    Anzahl Werte pro Kanal     4096

    Farbwerte-Tabelle

    Raster-Schritte       33

    Einträge    35937

    Ausgabe-Tabelle

    Kanäle       3

    Anzahl Werte pro Kanal     2048

    Charakterisierungsdaten            [331703 Bytes]

    Gerätefarbwerte           [331703 Bytes]

    Farbmesswerte              [331703 Bytes]

    Absolute to media relative transform    Bradford (ICC-Empfehlung)

    Matrix           0.8951 0.2664 -0.1614

    -0.7502 1.7135 0.0367

    0.0389 -0.0685 1.0296

    Roter Matrix-Farbwert

    Leuchtmittel-Bezug XYZ         58.66  30.29   2.13 (xy 0.6441 0.3325)

    PCS-Bezug XYZ           61.72  31.56   1.55 (xy 0.6509 0.3328)

    Grüner Matrix-Farbwert

    Leuchtmittel-Bezug XYZ         18.62  63.20   7.48 (xy 0.2085 0.7077)

    PCS-Bezug XYZ           20.38  63.06   6.46 (xy 0.2267 0.7015)

    Blauer Matrix-Farbwert

    Leuchtmittel-Bezug XYZ         18.04   6.52  97.70 (xy 0.1476 0.0533)

    PCS-Bezug XYZ           14.32   5.37  74.48 (xy 0.1520 0.0571)

    Rote Farbtonwiedergabekurve

    Anzahl Werte             256

    Übertragungsfunktion            ≈ Gamma 2.13 100% (Δ 3.50%)

    Minimum Y   0.0000

    Maximum Y  100.00

    Grüne Farbtonwiedergabekurve

    Anzahl Werte             256

    Übertragungsfunktion            ≈ Gamma 2.15 100% (Δ 3.68%)

    Minimum Y   0.0000

    Maximum Y  100.00

    Blaue Farbtonwiedergabekurve

    Anzahl Werte             256

    Übertragungsfunktion            Unbekannt

    Minimum Y   0.0000

    Maximum Y  100.00

    PCS zu Gerät: Anpassungsart 1

    Matrix           3.7668 -1.1229 -0.6171

    -1.8605 3.6968 0.1176

    0.1062 -0.2739 2.6324

    Eingabe-Tabelle

    Kanäle       3

    Anzahl Werte pro Kanal     4096

    Farbwerte-Tabelle

    Raster-Schritte       33

    Einträge    35937

    Ausgabe-Tabelle

    Kanäle       3

    Anzahl Werte pro Kanal     256

    PCS zu Gerät: Anpassungsart 2

    Matrix           3.9250 -1.2213 -0.6827

    -1.9575 3.8322 0.0668

    0.0574 -0.2813 2.6985

    Eingabe-Tabelle

    Kanäle       3

    Anzahl Werte pro Kanal     4096

    Farbwerte-Tabelle

    Raster-Schritte       33

    Einträge    35937

    Ausgabe-Tabelle

    Kanäle       3

    Anzahl Werte pro Kanal     2048

    Gerät zu PCS: Anpassungsart 1

    Matrix           1.0000 0.0000 0.0000

    0.0000 1.0000 0.0000

    0.0000 0.0000 1.0000

    Eingabe-Tabelle

    Kanäle       3

    Anzahl Werte pro Kanal     2048

    Farbwerte-Tabelle

    Raster-Schritte       33

    Einträge    35937

    Ausgabe-Tabelle

    Kanäle       3

    Anzahl Werte pro Kanal     2048

    Gerät zu PCS: Anpassungsart 2

    Matrix           1.0000 0.0000 0.0000

    0.0000 1.0000 0.0000

    0.0000 0.0000 1.0000

    Eingabe-Tabelle

    Kanäle       3

    Anzahl Werte pro Kanal     2048

    Farbwerte-Tabelle

    Raster-Schritte       33

    Einträge    35937

    Ausgabe-Tabelle

    Kanäle       3

    Anzahl Werte pro Kanal     2048

    Chromatizität (Leuchtmittel-Bezug)

    Kanal 1 (R) xy             0.6441 0.3325

    Kanal 2 (G) xy            0.2085 0.7077

    Kanal 3 (B) xy             0.1476 0.0533

    Gerätehersteller und Modell

    Hersteller      0x30AE Lenovo Group Limited

    Modell          0x4125

    Metadaten

    prefix             EDID_

    CMF_

    DATA_

    MEASUREMENT_

    OPENICC_

    MAPPING_

    ACCURACY_

    GAMUT_

    EDID_mnft    LEN

    EDID_mnft_id            12462

    EDID_model_id          16677

    EDID_date     2019-T0

    EDID_red_x   0.6455078125

    EDID_red_y   0.330078125

    EDID_green_x            0.2158203125

    EDID_green_y            0.7138671875

    EDID_blue_x 0.1455078125

    EDID_blue_y 0.0576171875

    EDID_white_x            0.3349609375

    EDID_white_y            0.3525390625

    EDID_manufacturer   Lenovo Group Limited

    EDID_gamma             2.2

    EDID_model  NE173QUM-N42

    EDID_md5             f88322788775b8d7767f170576580314

    CMF_binary  DisplayCAL

    CMF_version              3.8.9.3

    CMF_product             DisplayCAL

    Lizenz            Public Domain

    Quality          high

    OPENICC_automatic_generated         0

    DATA_source             calib

    MEASUREMENT_device         i1 displaypro, colormunki display

    MAPPING_device_id xrandr-Lenovo Group Limited

    ACCURACY_dE76_avg            0.318030

    ACCURACY_dE76_max           1.668955

    ACCURACY_dE76_rms            0.374568

    GAMUT_volume        1.48852434878

    GAMUT_coverage(dci-p3)      0.8576

    GAMUT_coverage(srgb)         0.9962

    GAMUT_coverage(adobe-rgb)            0.9654

    Attachments:
    You must be logged in to view attached files.

    i1Display Studio on Amazon   i1Display Pro on Amazon  
    Disclosure: As an Amazon Associate I earn from qualifying purchases.

    #30351

    Vincent
    Participant
    • Offline

    This is not related to DisplayCAL but to a 3rd party app (pic 1 & 3) that seems to be malfunctioning, or that you have misconfigured (simulate on teh fly some colorspace).

    #30355

    user3434343
    Participant
    • Offline

    no unfortunately, it is not. the 3rd party app is just measuring the native profile and the triangles I just putted in for clarificaiton. What you can clearly see is that there is a huge difference in the garmut precal and postcal with displaycal. It might be random that this is close to Rec709 what is left, but the main question is still, if there is a way to “limit” this huge loss of garmut after calibration. And no, you can say many things about lightspace, but they measure accurately… Again, the “triangles for colourspaces” are just for demonstration, they have NONE influence on the measurements… and the measurements are taken the SAME WAY precal and postcal… thanks!

    #30357

    Vincent
    Participant
    • Offline

    DisplayCAL is not doing it. IT CAN’T. It’s your 3rd party app fault or that you changed OSD mode in display to some gamut limitation or that you enabled AMD’s sRGB emulation of the fly from EDID data.

    Easy to test, use command line spotread on a 255 green patch in MS Paint application.

    • This reply was modified 4 months, 3 weeks ago by Vincent.
    • This reply was modified 4 months, 3 weeks ago by Vincent.
    #30363

    user3434343
    Participant
    • Offline

    The only thing which was changed in comparison to precal is that we loaded the displaycal generated ICC and activated it. Before for profiling with displaycal we used a null (or linear) icc which resulted in the large native garmut measurement. BTW, does displaycal disables the ICC automatically during profiling or also should load NULL icc?

    #30365

    Vincent
    Participant
    • Offline

    The only thing which was changed in comparison to precal is that we loaded the displaycal generated ICC and activated it. Before for profiling with displaycal we used a null (or linear) icc which resulted in the large native garmut measurement.

    No, it’s your app’s fault or user misconfiguration (simulation profile, using device link profiles… or such).

    Run a spotread on a non color managed app. It’s the smoking gun. A display ICC profile does not change display colorspace, it just describes it. It can change grey & white (VCGT tag loaded into GPU)

    BTW, does displaycal disables the ICC automatically during profiling or also should load NULL icc?

    In OS? yes, no need to change it.

    #30368

    user3434343
    Participant
    • Offline

    what do you expect to get from the spotread? Is it an app by itself?

    if the VCCGT is set (what should be), even in non color manageed application the display changes?!

    #30370

    Vincent
    Participant
    • Offline

    what do you expect to get from the spotread? Is it an app by itself?

    Spotread just measures a patch: on a display (emissive), on paper, on a facbric (reflexive) and prints CIE color coordinates.
    YOU provide the patch. Hence if display has a current colorspace ~AdobeRGB and MS paint is not color managed, 255 green is close to AdobeRGB green.
    Spotreading such patch on screen should return that.

    It’s YOUR 3rd party app that is producing sRGB like RGB patches encoded in display RGB colorspace. Why? you change OSD, app misbehaviour, app misconfiguration, GPU colospace simulation… etc.

    DisplayCAL measurement report can do the same, for example testing of your AdoberGB display behaves showing sRGB images on Ps. So YOU or 3rd party app are providing a set of modified patches encoded in display colorspace.

    Your issue is not related at all with DisplayCAL, jus 3rd party app misbehaviour or user misconfiguration operating that 3rd party app.

    if the VCCGT is set (what should be), even in non color manageed application the display changes?!

    VCGT just changes grey. It’s a 1D LUT to make grey have the same color tone as white. Yes, it is applied “globally”, system wide… but just for grey.

    #30371

    user3434343
    Participant
    • Offline

    ah ok understood. there is a similar function like spotread in lightspace, can compare this. However, the reason is for sure not in lightspace, but I can’t exclude that the app showing the patches might not properly recognize the ICC generated by displaycal. The patches are just shown in a video (we are using potplayer, which is configured to use ICC). Can you recommend a videoplayer for win10, which is known to properly use the full colormanagement and ICC?

    #30374

    Vincent
    Participant
    • Offline

    ah ok understood. there is a similar function like spotread in lightspace, can compare this. However, the reason is for sure not in lightspace, but I can’t exclude that the app showing the patches might not properly recognize the ICC generated by displaycal. The patches are just shown in a video (we are using potplayer, which is configured to use ICC). Can you recommend a videoplayer for win10, which is known to properly use the full colormanagement and ICC?

    Then it’s potplayer color management (madVR LUT3D? or ICC equivalent in potplayer) which reads video content colorspace (rec709?) and REENCODES RGB numbers to equivalent numbers in display colorspace (~AdobeRGB)
    Application recognizes displaycal profile without issues and taht video player IT’S WORKING AS INTENDED: content colorspace (~rec709) reencoded to display colorspace.

    It was your fault after all. You are not testing it in the proper way. A color managed video player MUST BEHAVE like what you saw: show RGB values (in display colorspace) that are equivalent to “rec709 only” patches (if video is/is supposed to be rec709).

    • This reply was modified 4 months, 3 weeks ago by Vincent.
    • This reply was modified 4 months, 3 weeks ago by Vincent.
    #30377

    user3434343
    Participant
    • Offline

    ok, got it. have to see how the patch video was encoded but you are probably right. Potplayer was ICC equivalent, not madVR LUT3d, because we wanted to directly test the performance of the ICC generated by displaycal).

    For the precal, is no problem, we can use madVRTPG.

    For the postcal, you are right, there is a problem. madTPG cannot be configured to use the ICC, right?  probably 3dlut only,  which then gives not a real idea about the performance of the ICC cal. No idea yet to show the patches in another way, cos u r right with the video…

    #30379

    Vincent
    Participant
    • Offline

    For the postcal, you are right, there is a problem. madTPG cannot be configured to use the ICC, right?  probably 3dlut only,  which then gives not a real idea about the performance of the ICC cal. No idea yet to show the patches in another way, cos u r right with the video…

    There is not ICC cal. ICC profiles are a description of a device.

    If you make a LUT3D from rec709 (video) to dispaly ICC with displaycal LUT3D maker you are indirectly testing if Rec709 portion of while Display colrospace is accurate.. with soem rounding errors due to the whole chain.

    #30555

    S Simeonov
    Participant
    • Offline

    I have an odd problem with using 3dlut in windowed overlay mode, the movies look kinda dark like crushed blacks or clipped blacks. This problem doesn’t occur in the other modes. The 3dlut has a gamma of 2.4 relative with black output offset set at 100%.

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