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I have gone through these steps here. I created the 3D lut for GUI Color Viewer, and went to my Resolve project settings, and selected the LUT, and pressed Save. No matter what LUT I choose, the GUI display doesn’t change.
How do I get the LUT to apply?
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Yes thanks I have it working. My only problem, I want to also use this same monitor for two things.
- Video (BT.1886 Gamma 2.4, Rec709, D65, 100cd/m2)
- Photography (Gamma 2.2, AdobeRGB or sRGB, 120cd/m2)
In this case, would it be better to just have two seperate LUT’s and switch between them in the OS?
I’m not sure this is possible, if I want to brightness settings, 100cd/m2 and 120cd/m2 between the video and photo modes.
I’m currently using Dell UP2716D, and have it set to “Custom Color” so I have access to Gain,Offset,Hue,Saturation controls. It has 2 memory slots, but that only works with Dell Calibration software.
In this case, would it be better to just have two seperate LUT’s and switch between them in the OS?
Only one profile is needed.
I’m not sure this is possible, if I want to brightness settings, 100cd/m2 and 120cd/m2 between the video and photo modes.
That’s a relatively small difference and probably not worth having to adjust the display for each separately.
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In this case, would it be better to just have two seperate LUT’s and switch between them in the OS?
Only one profile is needed.
I’m not sure this is possible, if I want to brightness settings, 100cd/m2 and 120cd/m2 between the video and photo modes.
That’s a relatively small difference and probably not worth having to adjust the display for each separately.
Photography uses sRGB/Rec709 with Gamma 2.2. Video now uses BT1886 with Gamma 2.4. How does one profile work for both?
In this case, would it be better to just have two seperate LUT’s and switch between them in the OS?
Only one profile is needed.
I’m not sure this is possible, if I want to brightness settings, 100cd/m2 and 120cd/m2 between the video and photo modes.
That’s a relatively small difference and probably not worth having to adjust the display for each separately.
Photography uses sRGB/Rec709 with Gamma 2.2. Video now uses BT1886 with Gamma 2.4. How does one profile work for both?
Profiles store monitor behavior an usually 1D LUT calibration to make grays neutral with a desired gamma.
Photography applications does not need that your display is calibrated to 2.2 gamma because they use profile info (monitor behavior) to transform values between “RGB values in an image encoded in a colorspace” to “RGB values in your display”.
You can have a 2.4 display gamma and as long as display profile stores that info a color managed app like Photoshop can render a 2.2 gamma encoded image as intended. Usually this transformation causes some rounding errors that not all software are able to avoid… but that is another story.Video editors or renders are not usually color managed. They expect that your display configuration (calibration) matches the configuration that video file was mastered for.
Some video editors or renders could use software LUT3D to do that color management, so they took as input RGB values of your video content (defined in a colorspace) and they ouput matching RGB values in your display’s colorspace. Those RGB values could be different in number value but they represent the same color. That is what you can do in Resolve or madVR.So answering your question and as an example you could use in your Dell’s Custom color mode, full gamut (do not change 6axis config), D65 white, 2.2 gamma and make a calibration & profile with DisplayCAL with that calibration target. It will make a calibration for GPU to get 2.2 gamma and it will create a profile storing your display native gamut. Photoshop or GIMP do not need more info to render properly an sRGB image in your display.
Then, if you wish to see Rec709 video content properly in Resolve, you can use that profile (that monitor behavior description stored in a ICM file) to create a LUT3D. LUT3D will take Rec709 content in your desired gamma (Rec1886 2.4 as you said) and output equivalent color values in your display colorspace. Use that LUT3D in Resolve.Just 1 profile for just 1 OSD mode (Custom Color OSD preset), use that profile to make 1 LUT3D for Resolve.
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If you want to use other software for video that it is not color managed you’ll need to use other OSD mode that matches better srgb/rec709 colorspace, like factory calibrated sRGB OSD mode. Then calibrate to Rec1886 2.4 on top of that in the hope that factory calibrated sRGB mode matches propely the boundaries of sRGB/Rec709.
That situation will need 2 profiles, one for each OSD mode and you’ll have to switch profiles in OS/DisplayCAL tray app when you change from one OSD mode to the other.***
Anyway, since your dell allows hardware calibration, if you have access to a i1DisplayPro/i1Pro/iPro2 you should try Dell’s software for hardware calibration (CALx slots), at least for photo use.
If it is not good you can always use DisplayCAL to fine tune grey neutrality, white and gamma on graphics card LUT calibration.
For example CAL1 for native gamut, D65, 2.2, 120cd/m2 and CAL2 for Rec709, D65, 2.4 , 100cd/m2 (CAL2 could be used in non color managed video editor/players). Two OSD modes, two calibrations, two profiles.
If white, grey neutrality of gamma obtanied with Dell software is not as good as it should be, use DisplayCAL to correct it at graphics card LUT (like with color management in apps, all graphics card are not equal and some oth them -like AMDs for example- deal better with “rounding errors”).Calibrite Display Pro HL on Amazon
Disclosure: As an Amazon Associate I earn from qualifying purchases.
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In this case, would it be better to just have two seperate LUT’s and switch between them in the OS?
Only one profile is needed.
So answering your question and as an example you could use in your Dell’s Custom color mode, full gamut (do not change 6axis config), D65 white, 2.2 gamma and make a calibration & profile with DisplayCAL with that calibration target. It will make a calibration for GPU to get 2.2 gamma and it will create a profile storing your display native gamut. Photoshop or GIMP do not need more info to render properly an sRGB image in your display.
Then, if you wish to see Rec709 video content properly in Resolve, you can use that profile (that monitor behavior description stored in a ICM file) to create a LUT3D. LUT3D will take Rec709 content in your desired gamma (Rec1886 2.4 as you said) and output equivalent color values in your display colorspace. Use that LUT3D in Resolve.Just 1 profile for just 1 OSD mode (Custom Color OSD preset), use that profile to make 1 LUT3D for Resolve.
Okay thanks. I think I got it. So if I use Dell “Custom Color” mode, and leave the RGB Gain at 100%, this should provide maximum color for AdobeRGB colorspace. Then in DisplayCAL, I choose “Video 3D LUT for Resolve”, Tone Curve BT1886, Create 3D LUT with (vcgt) disabled. Then that makes the 1D LUT for photo apps with maximum colorspace AdobeRGB, and then I load the 3D LUT into the Resolve viewer for Rec709 in the viewer.
The only downside is being stuck with one brightness 100cd/m2 with one preset. If I want higher brightness for photos, I will then need to use another calibration preset.
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Hmm. I think I may need to use 2 OSD modes. Because when I create the Resolve for Color Viewer LUT, and uncheck “vcgt”, the LUT doesn’t apply at all to this OSD mode. So it doesn’t calibrate color temperature for other apps. The LCD monitor just remains in Full Gamut mode, at the “unknown color temp” for all other apps besides Resolve and color-managed apps like Adobe Photoshop/lightroom that I can load the LUT into.
So if I need fully calibrated 6500k for photoshop, I need another OSD mode.
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With a Decklink card, does not matter if “Apply calibration (vcgt)” is enabled/disabled?
In the DisplayCAL Resolve guide for External Decklink, it doesn’t say anything about “vcgt”. Only with the GUI Viewer, it says to disable.
