VS10 incorrect black levels when in SDR or HDR

I don't think I've ever checked the old Dune's black levels. The new one had black clip issues in Dolby Vision.

No, don't set HDMI range differently in source and display. Set both the limited which then matches how content is encoded.

All HDR modes now have correct black clip with an insignificant margin of error.

With your projector, if you leave HDR in Auto, Profile 7/8 uses the HDR base layer natively and Profile 5 is converted to HDR10 using VS10 utilising the RPU. Levels are correct in both cases.

VS10 can be highly beneficial to your projector - you can convert HDR10/DV to SDR using VS10 (using RPU with all DV profiles) or you can convert DV to HDR10 using VS10 (using RPU again) or you can use LLDV and have native Dolby Vision.

The X7900 supports selectable quantisation ranges - ie limited and full. But as I say, choose limited because that's native to the content. Selecting different quantisation ranges on source and display will either result in black crush or expansion (too dark or too light) depending which way you do it.

Personally, unless you know how to import custom gamma curves and setup for LLDV, I'd go with the VS10 SDR option for both HDR10 and DV content - As I keep saying, the best HDR a projector can manage is SDR.

 

I should have mentioned that I use Lumagen for HDR to SDR mapping and DTM.

But those guys from linked video still claim in 2023 that there is a problem which can be mitigated by setting media player to Full HDMI range and display to limited (or Auto if it is correctly auto-sensing what is incoming).

So that is why I wonder if they have not tested using the newest FW for Zidoo / Dune / Zap or if maybe the problem still persists to some extent.

With LG C9 Oled when (and no Lumagen in the chain), when I set Dune Max UltraVision so same chipset as UHD3000 to Full LG will get crushed blacks and evidently something is not right.

When I do the same with Lumagen (which really is not a factor here as I don't do any EDID manipulation on it - I just mention it as it is in the chain for its HDR to SDR with DTM) and JVC X7900 no matter if is set JVC to Limited / Full or Auto it seems not to make a difference or at least not as profound as with LG.

I would like to figure out the correct way to confirm which combination of settings give me the most accurate PQ so I can put it to bed.

 

As Mark has mentioned, the correct way (widely debated and accepted) is to run the entire chain in Limited/Low.

 

This is only true if you are using VS10, because DV engine will cut levels, otherwise the correct setting is what DMDreview says. This can be easily checked with the Spears&Munsil HDR table test file.

https://kodi.wiki/view/Video_levels_and_color_space
Limited, Full, Limited -- Video Level CORRECT : WtW & BtB preserved, Zero scaling

 

This is on the old 1619DR right?

And which pattern are you referring to? - I'm not familiar with an HDR Table Test on the S&M discs - which one is that?

 

Yes, RTD1619DR.
This is the test file: https://mega.nz/file/H09U3AZR#xDsoC4Vye5_spIdP6kBsHLy-YOvlKiKJoLaH0_DhyIg

 

So for Dune RTD1619DR (and also Zidoo using the same chip) setting it to Full and Diplsay to limited is the way to go?

As quoted Limited - Full - Limited refers to media encoding - media player level - display level?

And the above stands true for Realtek native processing

What is the correct levels setting for VS10 engine?

I am glad that we are finally getting to the bottom of it.

Thanks

 

Unless I've woken up in a different parallel universe, this bears no relation to these media players at all (it refers to Kodi --> GPU --> TV, aka PC media playback).

This has been covered so many times....

 

Ah ok - that's the Colourspace Evaluation pattern (strangely cut with a white clip one - has it been re-encoded?) I wouldn't use that for quantisation levels! You can get a fair idea but you haven't got individual code values - that's not what that pattern's for.

I use the Advanced Video/Speciality/Dynamic Range Low & High which are clip patterns that increment in single code values.

Although Advanced Video/Evaluation/Dynamic Range Low & High are generally good enough but they are restricted to limited range, which is all that's needed.

So this is Realtek engine only, tested with "Advanced Video/Speciality/Dynamic Range Low" which runs from code value 4 to 105. (I've no idea why it starts at 4 and not zero, but it doesn't really matter).

With Limited Range on the box and Limited Range on the display, black clips at 64 perfectly for HDR10 (and 16 perfectly for SDR 8-bit - I don't have an SDR 10 bit pattern).

White clipping is a bit trickier because of the display tone mapping, but on a 1000nit display, using "Advanced Video/Speciality/Dynamic Range High" white clips perfectly at 723 for a 1000nit pattern in HDR10 (and of course 235 for SDR 8-bit pattern).

As expected, setting the box to full with the display on limited results in a way darker picture, crushing blacks and introducing ringing.

White clipping is very difficult to determine since, again, doing this introduces a lot of ringing. Bottom line, it ain't right!

 

Yeah, I'm kind of feeling like that - it's like deja-vu in the Matrix...

 

If I understand the Kodi graphs correctly that is not the case? Of course there might be much more to it as with PCs stuff gets quickly complicated for no reason due to layers upon layers of processing but my understanding is of Kodi graphs as follows:

Limited - Full - Limited

1st Limited is file encoding - 2nd is source processing (so GPU in PC or Media Player in our case) - 3rd is the display technology (PJ in my case).

Am I wrong?

 

I used MadVR and a PC for over 8 years....and finally threw in the towel and bought a proper (made for the job) media player. OS issues, drivers, level mismatch and OS devilry behind your back..the list goes on.

Just set everything to Limited/Low and enjoy watching content.

 

For VS10, use limited - limited.
If you don't use VS10, full - limited is the best settings to avoid banding, but you can easily check by playing the video linked above.

 

Admittedly you reduce banding in blue by doing that but you're killing the clip levels and introducing ringing.

 

Then it's possible that your projector works like this, LG OLEDs don't have this problem.

 

This was on my test Samsung Flatscreen. Also tried on a Sony with similar results but no ringing, so that must have been introduced by the Samsung.

The Sony however showed artifacts in the blue gradient, so the banding, although reduced, wasn't solved. Definitely not as much as it was with the Samsung. The Zidoo is obviously doing the same thing as it did with the Samsung, but the Sony is processing differently.

It's not really worth testing on my projector as the 15s resync when HDR modes change makes it impossible to do subjective comparisons.

This effect may be a result of manipulation of HDMI levels needed in the early days when VS10 SDR had a hugely raised black floor - difficult to say - it's a long time ago and I forget everything we did around that time.

In later models (and I notice, also the AML928) HDMI level control has been removed. It briefly returned in one internal test FW, but is gone again now...

 

To nick the smiley face pictograph, I think this all boils down to what happens in the player but also what happens in the display

It depends what's happening in the player, whether it's this:

or this:

I think it's the latter.

Then there are two options for how the display processes a full range signal when you lie to it and tell it it's limited range:

For the first case these:


And for the second case these:


I think my Sammy does it one way and the Sony the other.

My guess is the LGs do it the same as the Samsung only better.

But the bottom line is, the correct way is Limited to Limited. That way you always get the levels right. However, as always, it's worth experimenting because of the banding in blue.

Also worth noting though that in real life content, you seldom, if ever, see banding in 10-bit, despite poor performance in the blue channel.

Also worth noting that banding is a non-issue in VS10, including Dolby Vision, so is it really worth dicking about in settings every time you want to swap between HDR10 and Dolby Vision for a problem you're never going to see?

Interesting though.

 

@Markswift2003 - before you full Alice down the....., just to say, my LG Oled has no problems at all (I've ran more test patterns than the wife thinks is healthy for a grown man )

 

I know... I just get sucked in. I should really resist...

But it is interesting though...

 

And if your wife doesn't think you're stark staring mad, you're husbanding wrong