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What exactly is the option “Apply vcgt” in the 3DLUT section doing? Since it defaults to “ON”, I lieft it at that and I am fighting with red since the beginning..
As it was the only option untried, I turned it to “OFF” and the red coloration is gone. I have to re-measure, thoug,h, I accidently had the wrong RGB levels set. But cleary it improved things.
Someone pleas explain, what it does. Isn’t the 3DLUT supposed to do all the correction, anyway?
OK, ran profiling and LUT creation again last night, set up to be thorough and run a couple of hours. Without the vcgt option I now get the colors I expected (and had before) and guess what? – changing back and forth between using the LUT and using none I get no visible difference, haha! Ok, I have to go through a menu, so I cannot SWITCH inbetween the two states but it seems all the overly vivid colors I saw were impressive at a first glance, but due to mistakes made. I already suspected the projector to be that good and it seems there is proof of that now. Now that I would call a funny result of all the effort.. Well, I only watched some scenes now, but I took a close look. I will upload the file these days and hope that Florian takes a look and tells me, how much correction actually is applied. So I will watch a movie now and see, if I can spot any differences in my normal usage scenario.
What exactly is the option “Apply vcgt” in the 3DLUT section doing? Since it defaults to “ON”, I lieft it at that and I am fighting with red since the beginning..
As it was the only option untried, I turned it to “OFF” and the red coloration is gone.
That would indicate you had the 1D calibration applied twice on top of one another, once through the calibration that was applied to the 3D LUT, and then again through the same calibration applied via the graphics card videoLUT. You’re supposed to only have either-or. Under Windows, madVR automatically sets the videoLUT to linear with DisplayCAL created 3D LUTs (option “apply calibration” is therefore ticked by default, what it does is it applies the calibration to the 3D LUT so that the latter does the complete correction and then appends a linear calibration to the 3D LUT that madVR loads when the 3D LUT is in use. This generally leads to the highest quality results because it is independent of videoLUT bit depth). Not sure how Kodi does it under Linux, but it should read the appended calibration and load it into the videoLUT. If it doesn’t do that, it could be considered a bug (or shortcoming), and needs to be worked around by either making sure the videoLUT is linear during 3D LUT use, or not applying the calibration to the 3D LUT.
changing back and forth between using the LUT and using none I get no visible difference, haha!
If the projector is already accurate out-of-the-box then the 3D LUT hasn’t much to correct.
I guess the kodi-implementation doens’t take into account anything but playing back on a dedicated kodi-machine, video only. Then there is no need for any correction but video playback. The thread in the kodi forum didn’t give me any hints on that.
Figuring out my projector doesn’t get much better with the 3DLUT-correcton of course is kind of nice, since it proves my gear to (still) be top-notch, on the other hand it is kind of disappointing, since of course expectations arose in the process. Really funny, if I think about it.. 😉 It took quite some time and money to figure that out but on the other hand I learned a bit about the whole color-correction-process and after all it is a tine little bit better. Now at least I am capable of helping all the friend out, that would like a better picture but have no option of measuring it..
And rest assured, I’ll be back! 😉
