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Discussion Starter #1
Ok, I haven't been able to find anything on this. The closest is the 2017 LG oled calibration notes. Where they show the codes and what line up with % of greyscale. For instance 277 is the lowest on my LG B7A which corresponds to 27.1%. Is there anyway with out signal generator to properly calibrate HDR. Both HCFR and ChromaPure only seem to have 5% steps. I'm am using X-Rite i1 Display. I am also using Diversified video solution patterns for HDR 10 and Dolby Vision calibration. Any help would be greatly appreciated!
 

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Not really. Manufacturers such as LG and Samsung have been changing those control points from year to year and model to model. And there has been some speculation that the points change as you move away from the TV's default settings (think accordion). Ryan at DVS made a heroic attempt to keep up with the changing LG points, but it was futile. The short answer is no, you can't do multipoint grayscale for HDR/DV on one of these displays by disc alone. You can do a single point (100%) or two-point, but that's about it.
 

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Manufacturers such as LG and Samsung have been changing those control points from year to year and model to model.
Panasonic are doing something similar. For example, with the HDR presets in the GUI are labelled up to 100% (or IRE as they incorrectly use). In actuality, 100% equals 72.6% as an adjustment point so, you're unable to adjust over 72.6%. I can kind of see the rationale behind it but, the labels in the GUI should align to what you're actually adjusting. Fortunately with the DDC in CalMAN, it's clear what stimulus level you're adjusting and the levels measured can be configured to reflect this.

Paul
 

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Not really. Manufacturers such as LG and Samsung have been changing those control points from year to year and model to model. And there has been some speculation that the points change as you move away from the TV's default settings (think accordion). Ryan at DVS made a heroic attempt to keep up with the changing LG points, but it was futile. The short answer is no, you can't do multipoint grayscale for HDR/DV on one of these displays by disc alone. You can do a single point (100%) or two-point, but that's about it.
Wow, so there's nothing an enthusiast can do with out shelling out tons of cash? And its only for HDR 10. dolby vision has ire (it seems a bit wonky tho).
 

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Actually,DoVi doesn't have IRE, just (mis) uses the term. IRE is the acronym for "Institute of Radio Engineers", and is from the days of analog broadcasting. It isn't correct for digital video since it really refers to voltages.
Single or two-point grayscale adjustment isn't really "nothing". It just isn't as comprehensive as multipoint in SDR.
 

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Actually,DoVi doesn't have IRE, just (mis) uses the term. IRE is the acronym for "Institute of Radio Engineers", and is from the days of analog broadcasting. It isn't correct for digital video since it really refers to voltages.
Single or two-point grayscale adjustment isn't really "nothing". It just isn't as comprehensive as multipoint in SDR.
I get i can use the 2 point system. But if I wanted the comprehensive greyscale I have to shell out money instead of them doing steps. Is there any advantage to having them use code values over the normal?
 

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They obviously think there is. This may be related to tone mapping and what it does to the ST2084 luminance scale (EOTF) followed by both HDR10 and DoVi. Every display's tone mapping is different and directly affects what it can show in HDR.
 

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I get i can use the 2 point system. But if I wanted the comprehensive greyscale I have to shell out money instead of them doing steps. Is there any advantage to having them use code values over the normal?
Ryan that makes the DVS HDR and Dolby Vision test pattern sets provides these code values I think.

The challenge is the LG list them as full range 10 bit values, But you need to convert them to limited range 8 bit.

But for the 2017 TVs, I would recommend just doing the two point white balance for HDR10.


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@Freeman23 take a look at the second post on this page:
 

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@Freeman23 take a look at the second post on this page:
Why would they have them so packed together? Like it just doesn't make any sense. Thank you for everyone's help! I wish I could contact someone at LG to see if maybe they would have an answer as to why they do that? There gotta be some reason, right?
 

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Why would they have them so packed together? Like it just doesn't make any sense. Thank you for everyone's help! I wish I could contact someone at LG to see if maybe they would have an answer as to why they do that? There gotta be some reason, right?
Because the native panel is 2.2 gamma and when you apply a ST 2084 PQ curve to the 2.2 panel, the grayscale adjustment points are no longer evenly spaced.

I think there is a 2017 LG calibration thread in the forum you can read through, it is discussed in detail.


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Im having some big issues with calibrating HDR my tv is an oled b8 im using colormunki display device with hcf software, my issue is i can calibrate the 2pt white balance high 100% and 30% low no problem but when it comes to doing the full greyscale calibration the HDR pattern steps dont match up with my TV's steps ive tried numorous amount of different HDR patterns and no luck also when i do a full sweep in hcfr my luminance levels are much higher than the target luminance levels not sure what is happening ive tried mehanik HDR patterns for my oled b8 but when i adjust the rgb in my tv 21pt it does not corrispond with the patterns codes any help thanks
 
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