Originally Posted by LaurentW
That makes sense, I'll first set my preferred luminance and get the lowest values for dE afterwards.
Now, I have this:
- red dE 3.5
- green dE 0.7
- blue dE 4.1
- white dE 0.5
I suppose it's not bad but not yet perfect, I'll keep on trying.
Thanks for your time!
HCFR validates readings against some user configurable colorspace... lets say Rec709 gamma 2.2
Your display colorspace boundaries ARE NOT the same as Rec709/sRGB... they are slighty bigger although they intersect al 99% or whatever coverage manufacturer advertises.
That means that U2515H native gamut red is not
going to match Rec709 red CIE xy coordinates.
i1Profiler or DisplayCAL are going to calibrate ("fix") white point, brightess, neutral grey and gamma... and nothing more. Then they are going to apply that 1DLUT calibration in graphics card and measure display: what is calibrated white, grey, and RGB primaries (and other things). This info plus graphics card calibration is going to be stored in a ICM profile. Your slightley oversaturated R, G and B are going to be the way they were... but now its actual xy coordinates are recorded.
GIMP or Photoshop are going to use that info to do not send red "255,0,0" when an sRGB image has sRGB "255,0,0" but another slighty modified 3numbers that have in YOUR display the same xy coordinates.
HFCR is going to send reference RGB values (lets say "255,0,0") and it expects that display response will match reference colorspace "255,0,0".
So you dell calibration after i1Profiler or DisplayCAL may be not wrong... maybe you are measuring it in the wrong way.
If you want that your display behavior matches sRGB/Rec709 gamut boundaries closely you'll need one of the following:
-use 6axis controls if available in your display OSD (I'm not sure that U1515H has such feature, I would say "no", but check user manual)
-use an external LUT3D (not cheap comparect to your display cost)
-use applications with profile based color management (Firefox, GIMP, Photoshop.. etc) or applications with software LUT3D support like madVR, Reshade...etc (you can compute these LUT3Ds from ICM profile and reference colorspace)