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I've heard reports that doing a 1DLUT calibration for the HDR modes has a chance of increasing the peak brightness is this true, and if so what would be the best method for doing this, is it the same procedure as ConnecTEDDD mentioned in the other thread by either using YCbCr with contrast at 85 HDMI level low or RGB limited at Contrast 100?
 

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HDR has to have contrast set at 100 and video levels (16-235). Also, I don't think a 1DLUT would increase peak luminance, usually it is the other way around.
 

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Ah i see, is there any guide for doing HDR calibration for grayscale, and maybe matrix via colourspace for the OLED's?

i managed to make a SDR LUT, and upload it following TEDDs recommendation before i left the house for vacation, but i think i kind of used the wrong integration time, would period mode, and 1 sec integration with IIT set to 1.0 nits be better for a i1d3, or eventually what settings worked best for you guys when a i1d3 was used.
 

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HDR has to have contrast set at 100 and video levels (16-235). Also, I don't think a 1DLUT would increase peak luminance, usually it is the other way around.
On some of the older 2017 and 2018 LGs when you set the white point you would sometimes get more peak luminance if the set was out of tolerance from the factory but now as you say, LG has the WP set pushing blue so when you set the WP the peak luminance will almost always be less. Whether you set the WP in the SM or the 1DLUT makes no difference in the peak luminance value you finally get just different mechanisms as we all know.
 

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Discussion Starter #1,485
Say someone were to accidentally hit that reset. I'm assuming there's no way to get the factory calibration values back...right? I'm guessing this is "bad" and has negative impacts.
Hi,

I haven't used RESET personally to see if the values will default (192.192.192) or return to the factory 'calibrated' default (which are different pre TV units).

However, the feedback I had from a user with CX who pressed RESET, he said that the values went to the factory 'calibrated' values. (not to 192.192.192 as I said).

But they are many TV models per year. It's challenging to find out what is happening when you press reset to each TV model since we prevent users from pressing RESET.

Generally, I made the post about recommending the users not to press reset, as it is not required, and I was aiming to prevent any issue.

The default 'calibrated' factory values are useless as data values when you have instruments to calibrate the White Balance to your place.
 

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For HDR it's enough to set Oled light to the value that makes the panel hits 700 nits if you have a 2018 TV. If you have a 2019 just set the roll off to your peak brightness with the DC template. So far no custom 1DLUT and/or matrix 3DLUT gave better results than factory calibration which isn't bad at all. With the help of Leon (liberator72), I'm working on a method to beat those results but it won't be soon.
 

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For HDR it's enough to set Oled light to the value that makes the panel hits 700 nits if you have a 2018 TV. If you have a 2019 just set the roll off to your peak brightness with the DC template. So far no custom 1DLUT and/or matrix 3DLUT gave better results than factory calibration which isn't bad at all. With the help of Leon (liberator72), I'm working on a method to beat those results but it won't be soon.
Miki, i tend to agree as long as you set the WP in the SM which is what Leon's process specifies. But sometimes i get a set where the 1DLUT is not so great and you need to go in and manually calibrate it which is tough with the tone mapping active or do the 1DLUT. I can't wait to see what you come up with!
 

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Of course the SM WP is the first thing to set before any SDR/HDR calibration. I took it for granted ;)
 
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Discussion Starter #1,489
I've heard reports that doing a 1DLUT calibration for the HDR modes has a chance of increasing the peak brightness is this true, and if so what would be the best method for doing this, is it the same procedure as ConnecTEDDD mentioned in the other thread by either using YCbCr with contrast at 85 HDMI level low or RGB limited at Contrast 100?
The procedure we recommend the users to use, for any calibration mode (SDR/HDR/DoVi) is to re-calibrate with their meters the panel initially, using the Service Menu White Balance (RGB-High) controls.

LG does the same to the factory, but they use an SDR 80% patch.

For SDR, when you have Contrast 85 and use a 109% White patch to perform Pre-Calibration of White Balance using Service menu, starting with 192.192.192 values, you will have the highest dynamic range of the panel.

According to the instructions, keep one channel to 192 and reduce the other two channels only.

You will have the best possible pre-calibration of the TV.

For HDR/DV, since we use Contrast 100, you still have the highest dynamic range starting from 192.192.192.

The reports you see or 'marketing comments' have to do with the fact that a manual cal using regular TV controls (without using SM WB adjustments), can have less peak output from using 1D LUT.

For example, if your LG has to the SM WB 192.180.180, and you measure with a 10% patch, and you see that the TV has more Red, you will use regular TV menus to reduce red, so you reduce the peak output.

If you perform the same procedure in SM WB, if the TV has more red, you will increase the (green and blue (180.180 values) for the red to have better RGB balance, increasing your peak output.

When you are using 1D LUT, the TV will ignore the SM WB values, so it will see a RAW panel performance (which will require a large amount of data reduction to the video signal) to fix the problem.

So when you use data to fix RGB balance.

When you are calibrating SM WB, these controls are calibrating the panel directly as a panel, so it's not affecting the signal's data path.

So it will always have better image quality if you will not use 1D LUT but pre-calibrate the panel first to the SM for White Balance. (Link 1, Link 2)

When you are using 1D LUT, for all LGs from 2018-2019-2020, you will always have a problem with your calibration; it doesn't matter what the dE charts will say, the processing of the 1D LUT has issues.

Most of the problems will appear in HDR10/DoVi; as a lifted black is a typical problem (even if you send a UNITY 1D LUT), you will see the added issues.

Even if you load a 'reset' 1D LUT, you will notice the issues, and it will not require any calibration.

Generally, gradation becomes less smooth, and some other issues added when evaluating with patterns or real-content.

The group we have with LG TVs of hardcore users, we have done insane testing to find out all these problems, from 2018 we recommend only this method (Pre-Calibration SM WB and then use only 3D LUT).

Also, when you are using 1D LUT, you need to have contrast and brightness to default positions (BR50 & CR 85) + Color @ 50.

These default settings are not working for all users. Some panels need 51,52, other with more problems 60-65, even 68!.

So when you are using 1D LUT, you can fix a panel problem using different Brightness values.

Something we have seen only with CX is that for some users, Contrast 85 will provide clipping (or have less color luminance.

The only way to find out that problem and resolve it, you will have to use the RGB Separation chart available in ColorSpace (or LightSpace) and improve the RGB Separation before start the profiling. (Link 1, Link 2)

Its a problem of the panel, something is not visible when you will evaluate Contrast pattern (all bars will flash until

253) or Color Clipping pattern (all bars will flash until 253)

It will require to reduce to Contrast 80 and increase Color also (55 or more).

So you can fix the panel issue, which will provide insane low dE numbers after calibration.

I want to post a very detailed example one day, but it will require a whole day to write the info and post all the picture examples.

The point is that you can't provide any of those fixes when you are using 1D LUT, even if we don't count the problem with the processing of 1D LUT).

Another important detail, I'm sure users are aware...

When you have 1D LUT loaded to your TV, the TV will log somewhere internally a flag to not apply changes to the TV when you install a new FW version.

For example, when LG will release a fix to DoVi or any mode or an improvement somewhere, reduce dithering or improving some other processing (reducing compression artifact etc.).

In that case, the user will install the new FW expecting to see these improvements...

So when the user who has previously calibrated his TV using 1D LUT will install the new FW, he will not see any improvement! ...as the changes will not be applied to his TV!

That 1D LUT flag will stop TV for processing/receiving improvements! (started from 4.10.31 FW last year, see, I have video link also.)

So the user will have reset the 1D LUT to able his TV to accept the changes of the new FW.

LG did that for users who pay calibrators not to lose the calibration they have paid for, I mean 'basic' professional calibrators that use the default calibration procedure of 'next-next workflows'.

You will have to use Leon's method about DoVi/HDR10 calibration using ColourSpace without using 1D LUT.

There is an available full guide which explains the procedure, contact me to my site to provide it to you.
 

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For HDR it's enough to set Oled light to the value that makes the panel hits 700 nits if you have a 2018 TV. If you have a 2019 just set the roll off to your peak brightness with the DC template. So far no custom 1DLUT and/or matrix 3DLUT gave better results than factory calibration which isn't bad at all. With the help of Leon (liberator72), I'm working on a method to beat those results but it won't be soon.
So does that mean that you don't need to calibrate the grayscale in HDR mode or?

EDIT: nvm ConnecTEDD linked the procedure for grayscale calibration right after i posted.
 

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Discussion Starter #1,491
On some of the older 2017 and 2018 LGs when you set the white point you would sometimes get more peak luminance if the set was out of tolerance from the factory but now as you say, LG has the WP set pushing blue so when you set the WP the peak luminance will almost always be less. Whether you set the WP in the SM or the 1DLUT makes no difference in the peak luminance value you finally get just different mechanisms as we all know.
Hi John,

The Peak output will be the same if you pre-calibrate SM WB or use 1D LUT for that.

However, when you are using 1D LUT, you will add many more issues, as I have just posted, so it's not worth it.

The 2017 TVs don't have 1D LUT (with consumer FW), so performing Pre-Cal WB using SM, its the only method to have the maximum possible output.
 

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So does that mean that you don't need to calibrate the grayscale in HDR mode or?
There is no viable way to manually calibrate the greyscale in "HDR" mode. LG uses full range 10 bit Code Values for its multi point white balance controls. If you look at these you will see they are concentrated extremely closely together (if you convert into a percentage based scale), primarily towards the mid-luminance range of the scale. They also change dependent on the HDR metadata the TV receives(e.g. 1000 nit or 4000 nit). Any incorrect adjustment to these, however insignificant it may seem, will introduce banding and artefacts. It is safest to just adjust the 2 Point High (Low can be adjusted too, but is often not required) at around 65%-70%, and completely leave any and all CMS controls alone.

As Miki has said, we have been investigating HDR 3D LUT's, but as yet we have been unable to better the factory calibration in HDR. Although we have closely matched it, the effort so far required means that is also not currently viable.

Dolby Vision is different, as the multi point controls are spaced in normal 5% increments (with additional 2.5% and 7.5% for 2019/20), and colour management is by way of a configuration file. If you have a 2019 or 2020 LG you can use the method Ted linked to above.
 

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LG White Balance Pre-Calibration using Service Menu








It's a better solution to use a 2-Point RGB balance from one White Balance menu and not apply the same adjustments from both menus (regular TV menu + SM) simultaneously.
For SDR, are you adjusting the backlight for your preferred luminance here as well? I ask as one of the pics had it at 30 and the other at 100 (possibly for HDR). Thanks for this great writeup!
 

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Of course you have to adjust also the backlight setting to set your desired peak luminance. Don't forget to modify it also into user menu, it's not automatically done, at least on a 2018 TV
 

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Of course you have to adjust also the backlight setting to set your desired peak luminance. Don't forget to modify it also into user menu, it's not automatically done, at least on a 2018 TV
Right, I guess to clarify my question...Does the OLED light setting in the service menu (photo above) impact/change the same setting in the User menu or vice versa? I believe you are saying that it does not and you need to adjust both?
 

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Exactly, you need to adjust the OLED light in the user menu to the SM backlight after you have calibrated the WP.
 

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Discussion Starter #1,497
For SDR, are you adjusting the backlight for your preferred luminance here as well? I ask as one of the pics had it at 30 and the other at 100 (possibly for HDR). Thanks for this great writeup!
Hi Rob,

For 2019 TVs, it's not working the Backlight from inside SM WB; for other models, it's working. (its a TV bug).
 

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For SDR, are you adjusting the backlight for your preferred luminance here as well? I ask as one of the pics had it at 30 and the other at 100 (possibly for HDR). Thanks for this great writeup!
The pictures I used were old photos not related to the procedure. I think I used service manual pictures taken from LG SM manuals.
 

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Thank you for clarifying!! I am at 50 hours with my 77C9 and will be performing the pre cal SM WB adjustment and then Autocal the 3D LUT once I hit 100 hours. Gathering up all my notes. :)
 

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Sorry, as you wrote "Autocal" does it mean you will use CalMan to create a 3DLUT?
 
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