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	LG G5 - Confused about HDR 3D LUT calibration
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Wolf91074

ZRO

#1 | Posted: 4 Aug 2026 09:55

Hello everyone,
I tried to calibrate my LG G5 OLED in HDR Filmmaker mode with a HDR 3D-LUT.

First I profiled the HDR mode just out of the box with a 10-point-greyscale and a 10-point luminance at 50% level. (I assume, that at the 50%level one has no problems with OLED issues).
The first attachment shows the CIE diagram. Target gamut is ST2084 Rec2020, max. luminance changed to 2200 nits. As you can see, the colour saturation tries to target the Rec 2020 primaries, until the limitation of the display is reached.

Then I profiled the display with a 10-point cube based profile, and as augmentation I took a 40-point greyscale. (I'm aware that there might be problems with display stability, but in this case this does not to be relevant for me). In the next step I created a 3D-LUT as described of the ligthillusion site for LG TV integration under the "? HDR LUT calibration" button.
The second attachment shows the 10-point-luminance, 50% stimulus after 3D-LUT calibration. Target gamut is ST2084, but primaries changed to the display's primaries, taken from the colour space extracted from the profile. As you can see, color saturation does not try to target any more, but perfect matches the display's primaries.

So my question is: Why does the profile target the display's primaries after 3d-LUT calibration, not the Rec2020 primaries. Or did something go wrong here?

CIE Diagram HDR Filmmaker OOTB

CIE Diagram HDR Filmmaker 3D-LUT calibration

Colourspace Home/AV HTL LG TV TED
LG 65G5
xRite i1D3 OEM Dell
xRite i1Pro2 Rev. E

	Steve INF	#2 \| Posted: 4 Aug 2026 10:06
		The colour space being used for the 'verification' is not Rec2020, as the graph shows. It appears you have extracted the native colour space, and are using that? Steve Steve Shaw Mob Boss at Light Illusion

	Wolf91074 ZRO	#3 \| Posted: 4 Aug 2026 11:26
		Yes, I extracted the display's native colour spacee and used it as source for the creation of the new LUT, destination was the display profile (10 cube + augmentation).. Then I switched to "Apply to existing LUT", took the display's native colour space as destination and UHD Rec2020 as source, as described on the light illusion page (or did I do something wrong?): "LG HDR 3D LUT Calibration It is entirely possible to use 3D LUTs for HDR calibration of LG TVs, with the caveat that the inherent instability with any HDR TV, due primarily to heat related drift, can be difficult to manage. Basic Understanding For 3D LUT based HDR calibration, the 3D LUT actually targets a standard Power Law EOTF, with the LG TV applying it's own Power Law to PQ EOTF mapping on top of the calibration LUT TV Configuration The LG TV needs to be set to HDR mode, with calibration mode enabled. The Peak Brightness setting needs to be set to Not Active. Brightness, Contrast and OLED Light should at their maximum values. Profiling As usual, Upload a null Unity Bypass LUT, to make sure there is no existing calibration data active. Profiling can then be performed as normal, but with extended duration Stabilisation Patch times (3 seconds for example), as well as using a Quick Profile to keep the profiling times short, such using as Grey, Primary & Secondary Ramp+. The use if a fast probe is recommended - low-end probes such as the i1D3 are likely too slow, and will cause heat related drift issues. LUT Generation For LUT generation there are two options. The first targets the TV's Native colour space, using the Extract Space function with the Manage Spaces Modify option. Targeting the TV's Native colour space minimises the work the LUT Generation has to do, while correcting any volumetric issues. It has also been found that targeting a lower EOTF value of 2.1, rather than the TV's native value of 2.2 assists with the TV's internal PQ mapping. The Extracted colour space can also include any Alternative White Point, if one is being used. After the LUT has been generated, it then needs to be mapped into Rec2020 space, using the Apply to existing LUT option within LUT Generation, with the Source colour space being set to UHD Rec2020, and Destination set to the Extracted colour space." Colourspace Home/AV HTL LG TV TED LG 65G5 xRite i1D3 OEM Dell xRite i1Pro2 Rev. E

	Steve INF	#4 \| Posted: 4 Aug 2026 11:33
		Then that is your answer - you are not targeting Rec2020, as per the last step, as well as using a Rec2020 PQ colour space for the 'Target'. Steve Steve Shaw Mob Boss at Light Illusion

	Wolf91074 ZRO	#5 \| Posted: 4 Aug 2026 11:41
		sorry, still confused: I did everything as described on the light illusion page and expected a colour space targeting REC 2020, but got one targeting the display's colour space. Questions: Is that correct, should the display now target its own colourspace? If so, why? If this is wrong and the display should target Rec2020 as before, what must I do to get this? Colourspace Home/AV HTL LG TV TED LG 65G5 xRite i1D3 OEM Dell xRite i1Pro2 Rev. E

	Steve INF	#6 \| Posted: 4 Aug 2026 11:48
		The target colour space is what you set yourself. You use a colour space that targets the native display space during LUT generation. But then concatenate with a LUT that goes form the native space to Rec2020, as per the guide. Then you verify against a standard Rec2020 when checking the LUT. Steve Steve Shaw Mob Boss at Light Illusion

	Wolf91074 ZRO	#7 \| Posted: 4 Aug 2026 13:24
		Hi Steve, maybe this is a stupid question, but does this mean that I have to use the display's colour space as destination and the displays profile as source in the first step? In the second step the display's native colour space again as destination and UHD Rec 2020 as source, as I already did? Colourspace Home/AV HTL LG TV TED LG 65G5 xRite i1D3 OEM Dell xRite i1Pro2 Rev. E

	Steve INF	#8 \| Posted: 4 Aug 2026 15:53
		I'd have a read of the relevant User Guide: LUT Concatenation. Steve Steve Shaw Mob Boss at Light Illusion

	DNice ZRO	#9 \| Posted: 4 Aug 2026 18:46
		Wolf91074: Hello everyone, I tried to calibrate my LG G5 OLED in HDR Filmmaker mode with a HDR 3D-LUT. First I profiled the HDR mode just out of the box with a 10-point-greyscale and a 10-point luminance at 50% level. (I assume, that at the 50%level one has no problems with OLED issues). The first attachment shows the CIE diagram. Target gamut is ST2084 Rec2020, max. luminance changed to 2200 nits. As you can see, the colour saturation tries to target the Rec 2020 primaries, until the limitation of the display is reached. Then I profiled the display with a 10-point cube based profile, and as augmentation I took a 40-point greyscale. (I'm aware that there might be problems with display stability, but in this case this does not to be relevant for me). In the next step I created a 3D-LUT as described of the ligthillusion site for LG TV integration under the "? HDR LUT calibration" button. The second attachment shows the 10-point-luminance, 50% stimulus after 3D-LUT calibration. Target gamut is ST2084, but primaries changed to the display's primaries, taken from the colour space extracted from the profile. As you can see, color saturation does not try to target any more, but perfect matches the display's primaries. So my question is: Why does the profile target the display's primaries after 3d-LUT calibration, not the Rec2020 primaries. Or did something go wrong here? CIE Diagram HDR Filmmaker OOTB CIE Diagram HDR Filmmaker 3D-LUT calibration Basic method....... First, unity the 709 and 2020 3DLUTs. Do Not unity the 1DLUT! You also need to unity the 3x3 gamut matrix. Not sure if ColourSpace can do this without a unity 1DLUT (I don't use ColourSpace to do this step). Then, calibrate your grayscale to perfect 2.2 gamma with Peak Brightness set to High. This yields the best post calibration results Second, profile your G5 in Gamma Space, not PQ Space, with Peak Brightness set to OFF. Make sure the orbiter is turned ON and you set the stabilization patch option in ColurSpace to at least 3 seconds per patch with FW ticked and the FW background color set to 18 or 19 to manage drift. Third.... There are multiple ways to create the LUT for the G5. However, this method uses the least amount of steps: Create your LUT with via Mapped Space setting with the Source set to UHD Rec2020 customized with your target whitepoint and gamma 2.2. Test with Disable Gamut Mapping checked and unchecked to see which yield the least artifacts. Fourth, upload your LUT to the G5, turn Peak Brightness to High and validate your LUT using ST2084 Rec2020 (make sure you are using whatever whitepoint you chose to target). You can also play with 3DLUT with 1D corrections or 3DLUT with the 1DLUT stripped out.

	Wolf91074 ZRO	#10 \| Posted: 6 Aug 2026 07:10
		I have to apologize for this post. The problem was that the uploaded LUT wasn't active, even after I changed the picture mode or turned the TV off and back on. I unplugged the TV for 3 minutes, and that solved the problem. But now that the LUT has been successfully activated, I have to say that the results so far have been rather disappointing. Strange RGB balance and EOTF, black crush, and inconsistent results across different LUT creation modes. Could these be issues caused by the display's temperature drift? But that might be a topic for another post. Colourspace Home/AV HTL LG TV TED LG 65G5 xRite i1D3 OEM Dell xRite i1Pro2 Rev. E

	Steve INF	#11 \| Posted: 6 Aug 2026 08:50
		Post the profile as all the information on what any issues are will be in that. A bad LUT always means a bad profile, and the graphs are there to show you what the profile issues are. Steve Steve Shaw Mob Boss at Light Illusion

Wolf91074

ZRO

#12 | Posted: 6 Aug 2026 11:54

Hi Steve,

here's the profile

Attached file:
The Profile

Colourspace Home/AV HTL LG TV TED
LG 65G5
xRite i1D3 OEM Dell
xRite i1Pro2 Rev. E

	DNice ZRO	#13 \| Posted: 6 Aug 2026 13:15
		Your drift plot is terrible More than likely, it caused all of this with the LUT creation When you properly manage drift and have a better patchset, you can achieve the below: 10000+ points measured in HDR drift plot 16000+ points measured in HDR drift plot and LUT creation

	Steve INF	#14 \| Posted: 6 Aug 2026 18:01
		There is actually a bigger issue with that profile, although the drift is very bad. It seems the LG is already (badly) calibrated to Rec2020... That will always cause issues with LUT Generation, as explained in the user guides. If you have uploaded Unity/Null Bypass there should be no calibration active. Steve Steve Shaw Mob Boss at Light Illusion

	Wolf91074 ZRO	#15 \| Posted: 6 Aug 2026 18:15
		DNice Hi DNice, Thanks for your answer. I just checked the Service Menu settings, TCP and GSR are Both "Enable OFF", which is disabled, Dimming in Sub-Menu "System 1" is ON, however. Should this be disabled also? All the other settings , like energy saving etc. should be OK. Are there other settings in the Service Menu? Colourspace Home/AV HTL LG TV TED LG 65G5 xRite i1D3 OEM Dell xRite i1Pro2 Rev. E

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	LG G5 - Confused about HDR 3D LUT calibration

LG G5 - Confused about HDR 3D LUT calibration