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Hello!

I've got a replacement panel from LG for my C7 recently (due to burn-in on the old panel), and I'm having some problems with it. I've noticed this when watching movies, where I can see noise present in black parts of the image (e.g. letterbox bars). Also, near black levels seem to be unnaturally bright, causing posterization. I did not notice with the old/original panel

To be specific, when using standard unmodified Technicolor Expert (or Cinema Home) settings I have these problems:
  • Levels just above black are too bright.
  • There is noise in black parts of the image. The noise is "moving" even if I pause the image, so it's not noise from the image or video itself.
To reproduce the problems, I tried to use the "Mehanik HDR10 test patterns" downloaded from the OP in this thread. Using the test "01. Black level / 01. black-level-v1.mp4" I get these results:

A) Unmodified LG OLED TV Picture Setting "Technicolor Expert":
1. Reference black at level 64 is black, but level 66 is too bright:
View attachment 3035602

2. Noise in reference black:
View attachment 3035603

B) LG OLED TV Picture Setting "Technicolor Expert" settings, but Brightness lowered from default 50 to 48:
3. Black crush; All Black levels up to level 84 shown as the same complete black:
View attachment 3035604

4. No noise in reference black however (which is good):
View attachment 3035605


So based on this, do you think there is a problem with the replacement panel I got from the LG Service? Or what is an expected outcome of the test "01. Black level / 01. black-level-v1.mp4". :unsure:
My B8 has the exact same behaviour. Raised blacks (noise) at brightness 50, crushed blacks at 49. What I managed to do to alleviate the issue was raising black level to 51 and reducing Lower RGB values (2 point IRE) some (forgot the exact value). Now I have no "noise", but 68 is still invisible - a minor black crush. I saved this to "Cinema" preset, and left "Technicolor" at default 50 with the raised blacks, just in case if I notice any severe black crush.
 

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Hello,
I'm new to the forum and calibration so I hope someone can help guide me to the right direction.
I got my TV calibrated via Calman and now just trying to get HDR brightness and contrast correctly. However, I'm a little bit confuses about the procedure. I'm using MPC and MadVR to get the HDR pass through to my screen. my tv is Sony X900E. When I used the black level calibration video, MPC and MadVR successfully pushed the HDR signal to my TV. I know according to the manual, everything below 64 I shouldn't see anything. However, even though I have my brightness adjusted to the lowest setting But I can still see the bar below 64. May I ask if I'm doing anything wrong? Thank you all and I hope that someone can help me
 

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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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Discussion Starter #324 (Edited)
I know according to the manual, everything below 64 I shouldn't see anything. However, even though I have my brightness adjusted to the lowest setting But I can still see the bar below 64. May I ask if I'm doing anything wrong? Thank you all and I hope that someone can help me
Sounds like a range mismatch - try returning Brightness/Contrast settings to default values and check video card range settings (Full/Limited), madVR settings (16-235/0-255) and TV black level (High/Low). Also SDR APL clipping pattern from AVSHD.709 could be very helpful to setup ranges correctly.

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
If basic grayscale 5% or saturations readings are incorrect then I don't think there is much sense in trying to use LG specific steps. First you have to get credible PQ tracking readings from HCFR. Recheck HCFR settings (Preferences->References-> Color Space - Rec.2020 and EOTF - SMPTE 2084 HDR) and make sure TV switches into HDR mode while playing HDR patterns.
If there is codes/patterns mismatch for LG specific 20pt grayscale steps you can find all 1024 patterns steps in this post (link).
 

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Hi
Is there any chance of getting FULL SCREEN patterns for 20 point greyscale calibration?

I've got a Samsung q90t and when using the squares on the black background causes colour variations when calling up the settings menu to change the RGB balance.

(I'm not sure but its something to do with the undefeatable dynamic tone mapping, or something like that, which makes the samsung harder to calibrate)

For SDR I've got full screen patterns which work well, I'm just struggling to find HDR in full screen.

Or if anyone knows where I can download some from. I'm viewing the test patterns directly on the TV accessing the video files from my NAS.

Thanks
 

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Is there any chance of getting FULL SCREEN patterns for 20 point greyscale calibration?

I've got a Samsung q90t and when using the squares on the black background causes colour variations when calling up the settings menu to change the RGB balance.
Using full screen rather than 10% Windows for HDR is likely to cause other brightness problems for calibration, especially at higher luminance values. Better to stick with 10% Window, and only display&measure when no menu is visible. BTW, the HDR grayscale adjustment points on the Q90T are almost certainly not 5% steps; they are nowhere near 5% steps on the Q90R. The SDR grayscale adjustment points on the Q90R aren't 5% steps either.
 

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Discussion Starter #329

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Hi M-V,

I've clicked on the links you provided, but Google Drive says 'Access Denied'

I've sent request for access via Google Drive

Thanks (y)
Many thanks downloads all working now.

As thoth said its best to work with 10% screen, but worth trying to see if I get a better result.

Thankyou very much for your help

regards

b0b0r0ck
 
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