Cropped Dolby Vision with grey bars

I have only seen this issue once on the Z9X Pro, after I tried to test the Metadata HDR option in trying to send only HDR10 output instead of DV. Switched back to Auto, restarted the movie and issue was gone.

 

This issue was resolved in v1.0.65.

 

Just bought the z9x pro and updated to v1.0.65. Still getting gray bars in player led dv on lg c3. Tv led is better but only shows as 8 bit colour.

 

No problem with gray bars.

top right, search: Tunneling

 

Oh, thanks! Sounds like the 8 bit rgb tunneling Dolby Vision signal still carries the 12 bit within. So no loss in quality in tv led. I still find it odd the black bars are still raised to grey on the player led. I wonder if anyone else is having this issue and why?

 

@Markswift2003
I have the same problem with the Zidoo UHD3000 connected to my 77 inch C3 OLED. If I set Standard LED TV DV in the Zidoo, black is perfect. If instead I set Player led LLDV, the black level is too high and I am forced to lower it to 44. Is this normal? What can be done?

 

There seems to be a pattern here - LG displays, particularly the C3.

The Zidoos certainly don’t put out raised blacks any more so it has to be the display.

The issue raised on this thread is completely different, it’s to do with video background layers, not video, and again has been fixed a long time.

Can you post your EDID - there may be a fix in the Dolby block but I haven’t had it confirmed that it works.

Or just use TV Led.

 

@Markswift2003
Yes, the problem is different but similar to mine and not having found an already open discussion, I preferred to write here. By selecting "LLDV led player", the video quality is slightly higher so I would prefer to select "Player led LLDV" and not "TV Led". I attach my EDID. Thanks so much Mark

 

Ok, I'm afk at the moment but back tomorrow night, so I'll have a look then

If I forget, please @ me in this thread

 

@Markswift2003
Ok, thanks always

 

Ok, try this EDID:

https://mega.nz/file/MeJgjJ7S#CFQIxRDgpYTMlT50zTAqT1JuBcQwD6_B_T0RO8QwjN0

I don't know if this will work, but your EDID is strange for an LG one because T_MinPQ which is what defines the minimum nits in the Dolby Vision Block is set to 0.008 nits.

Usually, LGs are either 0.000 or 0.001.

What's also odd is that yoir C3 shows T-MaxPQ (maximum nits) as 900 but the last C3 EDID I saw was only about 600nits but this is probably due to difference in screen sizes.

Anyway, all I've done is change T_MinPQ from 0.008 to 0.000 so load this EDID and see if it makes a difference.

 

Thanks so much Mark. I'll try the edit and let you know

 

@Markswift2003
Hey Mark, everything works perfectly. The blacks are back to the correct levels and the Dolby Vision contents can be seen really well. I'm so happy, I'll never stop thanking you. Thanks again!

 

Wow!

I've learned something too then - I'll have to do some testing with this with other devices and see if this is a Zidoo problem or an LG problem.

Very interesting...

I'm really pleased it's sorted for you

 

It's an LG issue.

So it seems the EDID in the C3 does not match the display's capabilities - the Dolby Block shows minimum luminance as 0.08 nits, which as we've said is rather high for a flatscreen, especially a brand like LG.

Because LLDV essentially sends out a pre tone-mapped image in accordance with the Dolby Block, if the EDID says the min nits is 0.08 then it sends black at 0.08 nits.

And if the display can go below that so the display expects black at say 0.001 (or even 0.000) nits, then black will appear slightly grey.

So it's a bad EDID in the LG - something I've not considered before so I'm very grateful you brought this to my attention.

 

@Markswift2003
All very clear Mark. Happy to have been helpful to you and the community. One last question, is it more correct to set black to 0.001 or 0.000 nits? Or indifferent?

 

It will depend on the display but to be honest, it will make very very little difference.

Without calibrating I would choose 0.000 because even if you lose 0.001 nit in shadow detail, you will never notice and black is definitely then set at zero nits.

 

@Markswift2003
Thanks so much for the explanations. As soon as you have time and opportunity, could you modify and send me the edid at 0.001 nit? In order to try them both and choose the one I like best. Thanks again Mark

 

Here's 0.001 nit - let me know which you prefer or whether there is no difference:

https://mega.nz/file/oDwE2DKR#0wNKZ28qPSY3B_mC0h2y_nLNTYlHTWHY9lLpKp9AhnY

 

@Markswift2003
Mark thanks so much. There should be more people like you in this world. You were really kind and helpful. I'll try the edit this evening and let you know. Thanks again.