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Discussion Starter #281
Some follow-up questions:
1. What results do you get from the "01. Black level / 01. black-level-v1.mp4" test on your C9, with using "Cinema" or "Technicolor Expert" picture mode with default settings? Something like what my pictures show, or closer to what the manual shows?
2. Do you have any "before vs after" photos to share?
I'd say something in between. On my C9 default Cinema/Technicolor settings black is raised and 64 bar has some 'noise' - I believe that it's dithering LG started using few years ago. 66-68-72 are dark but visible.
After dirty manual fix with WB controls 64 is black, 66-68 are much darker and almost invisible from viewing distance. But by any means it's not a reference or correct result, ideally a calibration is required.
I've taken some photos but my phone camera struggles in low brightness.

3. Did you try just lowering Brightness, and if so what result did that have?
4. Is the WB setting better to correct these near black issues, compared to the Brightness setting? Because I notice section 3 in the manual you linked to says, "don't use the Brighntess slider, very likely it's broken in HDR mode.". But there is not explanation of how that conclusion was reached.
I can't say for sure for C9 but I've taken measurements from my previous LG OLED EF950 and raising Brightness setting raised whole PQ curve which is AFAIU wrong and undesired if you want to adjust only near black handling. WB controls are much more delicate.
 

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I've tried to use these HDR patterns to validate & calibrate my Samsung Q8DN TV for HDR but there is a issue with the output I receive from using them on my PC.

I can't get proper output levels in any way as far as I can tell.
There is some improper handling or setup occurring when playing these on my setup. I used MADVR, LAV Video codec & mpc-hc.

Basically I get too low luminance levels across the board. My display is marketed with 1500nits but using the HCFR test patterns provided I only could get 650nits peak luminance and the overall image is too dim/dark. Luminance levels are not tracking proper levels at all.
The other patterns are the same with defaults.
I tried changing settings between 16-235 & 0-255 in both MADVR & LAV Codec and also GPU graphics settings. Trying both RGB & YCbCr output but nothing gives a proper output.

Black level is either crushed @ 80-100 black with 0-255 levels or I can have 64 reference be displayed using 16-235 levels but that results in a grey black level.

I'm seeing HDR has something wrong in it... if you count 64 to 80. It's exactly 16 levels difference.
Are we seeing HDR being double compressed? It looks like it's being set with reference black for 80. 64+16 in general with a 0-255 signal path.
If I setup using 16-235 output levels I can have 64 be proper reference & cut-off for black but then it's with black being displayed as a grey and need interference from my display controls to lower the black level to have 64 as black but then I end up at the same crushed black levels as start.
I reckon there is a misconfiguration in general for HDR as it is. It's being improperly handled by the software?
 

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I've tried to use these HDR patterns to validate & calibrate my Samsung Q8DN TV for HDR but there is a issue with the output I receive from using them on my PC.

I can't get proper output levels in any way as far as I can tell.
There is some improper handling or setup occurring when playing these on my setup. I used MADVR, LAV Video codec & mpc-hc.

Basically I get too low luminance levels across the board. My display is marketed with 1500nits but using the HCFR test patterns provided I only could get 650nits peak luminance and the overall image is too dim/dark. Luminance levels are not tracking proper levels at all.
The other patterns are the same with defaults.
I tried changing settings between 16-235 & 0-255 in both MADVR & LAV Codec and also GPU graphics settings. Trying both RGB & YCbCr output but nothing gives a proper output.

Black level is either crushed @ 80-100 black with 0-255 levels or I can have 64 reference be displayed using 16-235 levels but that results in a grey black level.

I'm seeing HDR has something wrong in it... if you count 64 to 80. It's exactly 16 levels difference.
Are we seeing HDR being double compressed? It looks like it's being set with reference black for 80. 64+16 in general with a 0-255 signal path.
If I setup using 16-235 output levels I can have 64 be proper reference & cut-off for black but then it's with black being displayed as a grey and need interference from my display controls to lower the black level to have 64 as black but then I end up at the same crushed black levels as start.
I reckon there is a misconfiguration in general for HDR as it is. It's being improperly handled by the software?
Are you sure your PC is outputting HDR at all with these files? 0-255 / 16-235 is SDR, although it's possible the app may still refer to HDR's 0-1023 / 64-940 that way, however it's also possible you're just outputting in SDR with the contrast cranked up, which is why you'd never reach your TV's peak output. Also, even if your TV says it's receiving an HDR signal, not all apps will automatically display HDR correctly. Some may still process it as SDR within an HDR signal, and some may do HDR correctly only if set up correctly. If you have a 4K Blu-ray player that can play the files, I'd probably use that instead.
 

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Are you sure your PC is outputting HDR at all with these files? 0-255 / 16-235 is SDR, although it's possible the app may still refer to HDR's 0-1023 / 64-940 that way, however it's also possible you're just outputting in SDR with the contrast cranked up, which is why you'd never reach your TV's peak output. Also, even if your TV says it's receiving an HDR signal, not all apps will automatically display HDR correctly. Some may still process it as SDR within an HDR signal, and some may do HDR correctly only if set up correctly. If you have a 4K Blu-ray player that can play the files, I'd probably use that instead.
I could have said Limited range and Full range but it's 0-255/16-235 in the options for the applications. Nothing as far as I've seen mention the true 0-1023/64-940 ranges expected from 10bit RGB output in PC software. (it's not ready for general usage, all is designed for 8bits)
Only HDR content make use of 10bits as far as consumers are concerned.
But HDR is working, the question is why does it clip to 80 target with all options when HDR is used? I was expecting a software issue but I'm more and more inclined to believe the TV is at fault.
 

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I have an issue trying to confirm proper black levels on my C9. After setting brightness in HDR at 49 I now get correct black levels and no issues with elevated blacks other than some content known to be incorrectly mastered. Using the black level patterns from 01. black-level-v1.mp4 I see 80 flashing while 76 is off. Using 01. black-level-v3.mp4 I have 84 flashing and 80 off. Both with same settings using Cinema and Technicolor mode. For reference I have peak brightness OFF, DTM ON but OFF is no change. Why isn't 80 visible on the other pattern? The first pattern actually shows 80 with good visibility which makes me think 78 would be visible as well. Are there any other test slides that I could try?

Edit: I also tried using brightness at default 50 with WB 2 pt at -6 each. It now shows a very faint glow at bar 68..almost invisible and the rest follow very nicely thereafter. It think it looks better once DTM compensates for the loss of overall brightness. Any issues that could arise from this?
Edit2: I looked closer in a darker setting and can now see bar 66 flashing with the WB "fix". Would've liked to see bar 80 little brighter though. Any way I can do that?
 

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Hi, at the factory, LG is calibrating only RGB balance with three color temp modes (cool, medium, warm) using one gray patch.
This is what FlatpanelsHD says about it in the review of the C8:
"we should also compliment LG for offering several very accurate picture modes, including ISF and Technicolor (see the graph for ISF below – Technicolor is not included as it is very similar). Honestly, with so accurate colors out-of-the-box investing in a full calibration to gain the last few percentages seems like overkill for most users. LG’s HDR modes still need calibration, however."

And in the review of the CX:
"Now that TVs from several brands in recent years, including LG, come pre-calibrated to quite high standards (from a consumer perspective), recommending optimal picture settings becomes mostly an exercise in tweaking the built-in picture modes."

So based on the above my understanding is that at least for some of the SDR picture modes, the later LG TV models come with some degree of pre-calibration done at the factory.

In my case I have a C7 though, and the reviews above were for C8 and CX, so I'm not sure what pre-calibration has been done on my C7.
 

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I could have said Limited range and Full range but it's 0-255/16-235 in the options for the applications. Nothing as far as I've seen mention the true 0-1023/64-940 ranges expected from 10bit RGB output in PC software. (it's not ready for general usage, all is designed for 8bits)
Only HDR content make use of 10bits as far as consumers are concerned.
But HDR is working, the question is why does it clip to 80 target with all options when HDR is used? I was expecting a software issue but I'm more and more inclined to believe the TV is at fault.
Note like I said, even if Windows itself is outputting HDR, the application may not be, which could be causing your issues. That would result in Windows converting the SDR image the app sends out into an HDR format, but doing so would not give you your peak luminance, nor would it be the correct EOTF. HDR in windows is a tricky situation right now. If it's converting to SDR, that could also be the cause of your clipping situation.
 

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Note like I said, even if Windows itself is outputting HDR, the application may not be, which could be causing your issues. That would result in Windows converting the SDR image the app sends out into an HDR format, but doing so would not give you your peak luminance, nor would it be the correct EOTF. HDR in windows is a tricky situation right now. If it's converting to SDR, that could also be the cause of your clipping situation.
It's not SDR... I know it. I only get 200-300nits if it's SDR content in HDR, if even that without tweaks.
I will be trying a custom ranges 8-255 12-255, 4-255 etc with other combinations if I can pull back those 16 black levels from 80->64.

EDIT... Seems 4 is the right adjustment but elevates black.. Would need to have it done on the Codec level rather than in MADVR at the output level. Though codec allows no custom ranges...
4 is 1/4th for 16 if put into = 16 if expanded into 0-1023 range...
There is a conversion level issue for HDR somewhere I guess. Does a improper compression of HDR with a extra 16-(235) video level adjustment.
Could be GPU driver, the TV or codec/MADVR.

Somewhere in the chain in HDR mode the 64-940 HDR 10 bit output is having a extra 8bit 16-(235) Video Level adjustment applied to the output. Crushing black & limiting peak luminance. We basically are getting a 80-920 Video level for HDR output.

EDIT2: Ok I tested the internal player on the TV with a USB and it does the same thing, Though a bit better at it.
So it's a issue with the TV and not the software setup incorrectly after all.
 

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Discussion Starter #289
Edit: I also tried using brightness at default 50 with WB 2 pt at -6 each. It now shows a very faint glow at bar 68..almost invisible and the rest follow very nicely thereafter. It think it looks better once DTM compensates for the loss of overall brightness. Any issues that could arise from this?
Edit2: I looked closer in a darker setting and can now see bar 66 flashing with the WB "fix". Would've liked to see bar 80 little brighter though. Any way I can do that?
I think that the main issue with eyeball WB adjustments is that we can't really examine how much brightness and white balance really shifted - it could become slightly visually better in one area (e.g. correct black level) but much worse in other areas (wb/color shift/brighter shadows/banding/etc). Further finetuning could be done with 20/22 WB controls but I don't think that they should be touched without taking some measurements with a sensor/colorimeter during calibration.
 

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I'can't say for sure for C9 but I've taken measurements from my previous LG OLED EF950 and raising Brightness setting raised whole PQ curve which is AFAIU wrong and undesired if you want to adjust only near black handling. WB controls are much more delicate.
Regarding the photos you posted, where they from your C9 or your EF950? Anyway, looking at your first grey scale picture, it looks much better than the pictures I posted from my C7 (with replacement panel). Don't you agree?
 

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Yes that's always a risk with eyballing a setting but it's the best I can do without a pro calibrator. In the end I settled with WB -3 for each of the RBG values in HDR10 cinema mode. Looks more correct than brightness at 49 which would crush everything below 0.005 nits. No longer having any noticeable issues with near-black overshoot unless it's source-related like those early Universal discs.


I think that the main issue with eyeball WB adjustments is that we can't really examine how much brightness and white balance really shifted - it could become slightly visually better in one area (e.g. correct black level) but much worse in other areas (wb/color shift/brighter shadows/banding/etc). Further finetuning could be done with 20/22 WB controls but I don't think that they should be touched without taking some measurements with a sensor/colorimeter during calibration.
 

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Discussion Starter #292
Regarding the photos you posted, where they from your C9 or your EF950? Anyway, looking at your first grey scale picture, it looks much better than the pictures I posted from my C7 (with replacement panel). Don't you agree?
Photos are from C9 and I don't think that photo comparison is very fair (different TV, camera and environment) but seems that C9 is looking better. However, common problems: elevated black, noise. LG slightly improves near black handling every generation but still very far from ideal.
 

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Yes for all the talk of OLED not being bright enough (not true btw) the near-black performance is still the biggest issue on these sets. At least they fixed uniformity issues that plagued the early models. This is why I feel a little black crush is necessary on LG OLEDs.

Photos are from C9 and I don't think that photo comparison is very fair (different TV, camera and environment) but seems that C9 is looking better. However, common problems: elevated black, noise. LG slightly improves near black handling every generation but still very far from ideal.
 

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This is what FlatpanelsHD says about it in the review of the C8:
"we should also compliment LG for offering several very accurate picture modes, including ISF and Technicolor (see the graph for ISF below – Technicolor is not included as it is very similar). Honestly, with so accurate colors out-of-the-box investing in a full calibration to gain the last few percentages seems like overkill for most users. LG’s HDR modes still need calibration, however."

And in the review of the CX:
"Now that TVs from several brands in recent years, including LG, come pre-calibrated to quite high standards (from a consumer perspective), recommending optimal picture settings becomes mostly an exercise in tweaking the built-in picture modes."

So based on the above my understanding is that at least for some of the SDR picture modes, the later LG TV models come with some degree of pre-calibration done at the factory.

In my case I have a C7 though, and the reviews above were for C8 and CX, so I'm not sure what pre-calibration has been done on my C7.
Hi,

LGD calibrate the panel to the factory.

LGD provide the panels with the Calibration of the panel stored to the TCON (not the White Balance calibration, but the gamma 2.2 based calibration as the OLED panels natively are linear 0-1 to their response)

After they receive the panels, LGE's assembling factory performs some testing using full-field patterns and others for some days. Then they perform the automated white balance calibration:


They calibrate 1-Point Grayscale with a full field 80% pattern, for three different color temp modes, nothing else.

Then the LG has some generic gamut mapping internally for REC.709 and REC.2020, and these corrections are the same for all TVs of the same model/year.

The site you have linked performs an automated process to calibrate 26-Point Grayscale and then only three colors.

So they press a button, you can't call the person who clicks that button that knows about Calibration, since anyone with zero calibration experience can click the AutoCAL button.

Also, evaluating a panel performance by taking six color measurements does not provide any accurate panel performance info.



If you want to see a professional review with 1000 color points for volumetric Calibration of a CX, then know that review:


For understanding the capability of a calibrated TV, the typical grayscale and ColorChecker measurements are not enough.

When you perform volumetric measurements and have software with tools for volumetric plotting and cube viewer, you can see real performance.

You can see a quick example with Sony AF9, which took all the awards in on-line reviews. However, all these guys performed the evaluations of using typical/limited methods:

I have posted some testing using that method to explain the volumetric issues of Sony OLED, typical non-volumetric measurements can't reveal:


 

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Photos are from C9 and I don't think that photo comparison is very fair (different TV, camera and environment) but seems that C9 is looking better. However, common problems: elevated black, noise. LG slightly improves near black handling every generation but still very far from ideal.
Ok, well how can a user tell whether their TV unit performs as can be expected from the model, of if they've got a fault unit?

From what I remember my previous C7 has much better greyscale performance. And the replacement panel I got from LG service certainly performs worse than your C9.

So how can the consumer know what is acceptable or not when running the tests in this "Mehanik HDR10 test patterns" test suite? Without anything to compare to, what good is the test suite? :unsure:
 

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Discussion Starter #296
Ok, well how can a user tell whether their TV unit performs as can be expected from the model, of if they've got a fault unit?

From what I remember my previous C7 has much better greyscale performance. And the replacement panel I got from LG service certainly performs worse than your C9.

So how can the consumer know what is acceptable or not when running the tests in this "Mehanik HDR10 test patterns" test suite? Without anything to compare to, what good is the test suite? :unsure:
Pattern set provides tons of different tests and calibration patterns but it is a set of tools, not a solution. I've already posted a link to a manual with some good/bad examples and photos from my set, so you can compare and decide if it is acceptable or not. Also you can try asking other users with same model w/wo replaced panels. If incorrect black level and grayscale are the only problems, then I think it can fixed with calibration to some extent. But if there are other problems (uniformity, banding, dead pixels, etc) or if you're not happy with your set overall or not even sure if is faulty or not, it's better to call TV seller or service and describe your problem and discuss with them how to deal with it.
 

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If incorrect black level and grayscale are the only problems, then I think it can fixed with calibration to some extent.
The FlatpanelsHD review of the B7 (which should be very similar to C7) says:

"Luckily, LG has included two ‘ISF Expert’ modes – one for dark room viewing and one for bright room viewing – and these are in a totally different league. The two color modes offer very accurate colors and with relatively modest adjustment we reached an impressive result.
[...]
We do not calibrate for HDR yet but should probably say that doing so requires a little more effort than described above (for SDR) because the default HDR modes are not as accurate as the ISF Expert modes."


I do not understand why LG would perform some factory calibration for SDR modes, but not for HDR modes though?

Also, I wonder if this has improved in the C8-CX model, so HDR calibration is done for those models in factory too?
 

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The FlatpanelsHD review of the B7 (which should be very similar to C7) says:

"Luckily, LG has included two ‘ISF Expert’ modes – one for dark room viewing and one for bright room viewing – and these are in a totally different league. The two color modes offer very accurate colors and with relatively modest adjustment we reached an impressive result.
[...]
We do not calibrate for HDR yet but should probably say that doing so requires a little more effort than described above (for SDR) because the default HDR modes are not as accurate as the ISF Expert modes."


I do not understand why LG would perform some factory calibration for SDR modes, but not for HDR modes though?

Also, I wonder if this has improved in the C8-CX model, so HDR calibration is done for those models in factory too?
Your answer is there: HDR10 test patterns set

FSI post-production monitors (based to LG WRGB panel) sold pre-calibrated for 3D LUT using ColorSpace for 5000 colour points:


No other LG OLED sold (parametrically pre-calibrated) for all modes.

The only calibration LGE is doing is a simple 80% full field gray calibration, for 3 color temp. (so 2 are useless if we talk about calibration)...o robotic system...not from human...

Humans see only if there any error to the SM screen.

Then all TVs use a generic correct for each picture mode, it means the same correction for the same panel model.

It will increase a lot the retail price from LG, to able to calibrate parametrically any TV they ship.

It will never happen in the consumer world.

Just ISF mode has fewer errors compared to other picture modes, where they have a lot of more errors.

The site you have linked is a basic review site that follows some guideline LG or other brand is sending to reviewers, not any serious site related to calibration.

They are many sites like that one, and just companies sponsor them with software/hardware for promotion.

You can see that they don't know how to calibrate if you compare ISF's dE color errors before calibration compared with post-calibration.

Post-Calibration increased the errors (if you count the scaling mismatch they have)

So they don't know how to calibrate; it's pointless to review and comment on how the TV can be calibrated when they don't know how to calibrate.

Calibration requires some basic understanding of how stuff works and how the controls work manually.

When you can calibrate manually, you will not use automatic calibration for just grayscale, unless you want to reduce the total required time.
 

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Answer to which of the questions? Did not find any explanation to why SDR could be calibrated in factory, but not HDR.

Humans see only if there any error to the SM screen.
Please clarify.

It will increase a lot the retail price from LG, to able to calibrate parametrically any TV they ship.
Why? Why would it not be possible to calibrate in factory using CalMAN calibration support in recent OLED models?

Just ISF mode has fewer errors compared to other picture modes, where they have a lot of more errors.
So calibration in factory is possible after all (for ISF mode), despite that it should be hugely expensive from what you said previously?

The site you have linked is a basic review site that follows some guideline LG or other brand is sending to reviewers, not any serious site related to calibration.
FlatpanelsHD does not know how to calibrate? Really? Please clarify.

Post-Calibration increased the errors (if you count the scaling mismatch they have)
Please clarify.
 

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Please clarify.
You need to know some more in-depth details about how LG work to understand.

Panels are gamma 2.2 based, and there is offset to convert the high-brightness SDR panel response to HDR.

So you are not calibrating HDR! But you calibrate SDR in high brightness mode for gamma 2.2 ... and the offset (tone mapping) convert to HDR10.

Even when you calibrate in HDR mode, you calibrate with disabled that HDR PQ offset.

It's impossible to calibrate any TV to any consumer factory parametrically as the whole manufacturing process has to change only for that.

It will increase the price of the product also, there many issues for all that, its consumer market; I don't have time to explain how the TV industry works, sorry.

The calibration performed by Flatpanels is not complete as they used only 2-Point Grayscale in SDR.

They say that TV has 10-Point Controls for parametric, but LG TVs from about 2008 they have 20-Point.

So they have no idea even how many Points it has the TV, B7 has 20-Point RGB Balance.

So they did only 2-Point RGB balance for SDR (5 minutes) and haven't used 20-Point, or CMS controls.

It's the reason the post-calibration has more color errors.

You can see the CIE chart also.

They haven't performed HDR calibration because it is more complicated.

So what kind of review is that for talking about calibration results as they haven't performed a complete calibration.
 
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