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Hi, I am the owner of an OPTOMA UHZ 65 laser projector, I am currently trying a 3dlut in SDR DCI, which I use for CONVERT HDR CONTENT TO SDR BY USING PIXEL SHADER MATH, in this regard I wanted some clarifications: 1) in DISPLAY & INSTRUMENT, being my vpr a laser, I have to choose REFRESH (GENERIC) or LCD and I have to flag WHITE LEVEL DRIFT COMPENSATION? 2) The white point I make it from the vpr, so in CALIBRATION I use AS MISURED, to the question DO YOU WANT THE 3DLUT TO USE THE MEASURED WHITE POINT …., I have to say yes, right? 3) In PROFILING I have to use MINIMIZE LIGHTNESS …. or MAXIMIZE LIGHTNESS …. 4) In 3DLUT in RENDERING INTENT do I have to choose ABSOLUTE COLORIMETRIC WITH WHITE POINT SCALING or RELATIVE COLORIMETRIC? I ask because in what I understood RELATIVE COLORIMETRIC is used only when creating the profile, while ABSOLUTE COLORIMETRIC … when calibrating and profiling is right?
Hi,
1) in DISPLAY & INSTRUMENT, being my vpr a laser, I have to choose REFRESH (GENERIC) or LCD and I have to flag WHITE LEVEL DRIFT COMPENSATION?
probably a good idea to enable that option for a projector unless you are 100% certain that the light output is stable at all times (I’m not sure how laser projectors work in that regard).
2) The white point I make it from the vpr, so in CALIBRATION I use AS MISURED, to the question DO YOU WANT THE 3DLUT TO USE THE MEASURED WHITE POINT …., I have to say yes, right?
Correct.
3) In PROFILING I have to use MINIMIZE LIGHTNESS …. or MAXIMIZE LIGHTNESS ….
Use “Maximize lightness difference” only if your projector has some sort of ABL (automatic brightness limiting), otherwise “Minimize display response delay”.
4) In 3DLUT in RENDERING INTENT do I have to choose ABSOLUTE COLORIMETRIC WITH WHITE POINT SCALING or RELATIVE COLORIMETRIC?
Should already be set to “Relative colorimetric” after confirming 1)
I ask because in what I understood RELATIVE COLORIMETRIC is used only when creating the profile, while ABSOLUTE COLORIMETRIC … when calibrating and profiling is right?
No. “Relative colorimetric” means use current display whitepoint (regardless what it is) unchanged, “Absolute colorimetric” means match the input colorspace whitepoint (usually D65) within the display gamut.
thanks for the reply ….. I just wanted to ask you something, my vpr covers 110% of BT.709 and only 80% of the DCI-P3 to qIn this point, it is better to make a 3dlut for convert hdr to sdr with pixel shader math in BT.709 or in DCI-P3
it is better to make a 3dlut for convert hdr to sdr with pixel shader math in BT.709 or in DCI-P3
If you are talking about 3D LUT input profile setting, neither. The correct choice is always Rec. 2020, because that is the container format used for HDR material. If you’re talking about a projector’s own gamut setting for profiling, use the largest gamut available (e.g. “native”).
I meant in the 3dlut screen displaycal ….. so I have to choose not dci-p3 but BT.2020 to do the conversion from hdr to sdr?
With the conversion hdr to sdr with pixel shader math the range must be set to 2.2 with bt2020 in the 3dlut screen?
You mean when you want to create a SDR 3D LUT to be used with madVR’s HDR to SDR pixel shader? Yes, in that case use gamma 2.2.
thanks for the answer …. so summarizing to make a 3dlut to use with convert hdr to sdr using pixel shader math in DISPCAL in the 3dlut screen I have to put bt2020 and range 2.2? ….. At this point in which cases you need choose dci-p3?
