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I have a C7 which was calibrated by a THX calibrator and ran some tests on this last night using the DVS patterns linked above. It's always bothered me that from time to time in a dark room I can see elevated black levels with DV.



What I found is that DV for me appears to have *slightly raised blacks* whether it's through HDMI or the internal apps. This was true whether I was using the calibrated Cinema (user) mode or the stock Cinema Home setting. Also, in general, I found the DV test patterns to be much darker than the HDR10 equivalents. With HDR 10 using the Black Clipping test patterns, I could see almost all gradations above 0%. Easily from 0.9% upwards. With the Dolby Vision test patterns I could only see starting at about 2.7%.


To test for raised blacks I would turn all the lights off and play the Black Clipping 2 test pattern which has a series of bars from 0% to 5%. I would then enter the Brightness control on the TV and move it one notch in each direction, around 48-52. While watching the screen very closely and carefully, in all cases, I could see a tiny amount of brightness emitted from the black background as soon as I went from 49 to 50. This means the panel is not showing 100% black at brightness 50. Brightness 49 "fixes" the problem but exacerbates the black crush issue, meaning I couldn't see any difference in the Black Clipping patterns until about 3.2% or more. I tried messing with OLED light to see if it would offset the issue but it doesn't. Perhaps using Brightness 49 could all be worked out in a finer-grained calibration, really going ham on the 20-point values at the lower end. I'm not sure.



Scenarios:
ATV4K (Firecore Infuse app) > STRDN1080 > C7



Oppo 203 (SMB share) > STRDN1080 > C7


C7 (Plex app)


All scenarios showed identical issues with DV. So I don't know to what extent this is limited to being an ATV4K problem.
 

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Yeah, even if you look at something like the opening credits to Blade runner, the black screen between names is slightly above black with DV with internal apps and hdmi devices, when the HDR10 version it’s true black.

I swear it didn’t used to be like this though. Something changed when LG implemented their HDMI DV “fix”. Like how the opening credits to Mute used to be true black. Maybe something on the mastering/grading side need to change too and just hasn’t caught up yet, but with DV we’ll never know.

I wish people had Panasonic oleds. I’d like to know if they have the same issues.
 

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Yeah, even if you look at something like the opening credits to Blade runner, the black screen between names is slightly above black with DV with internal apps and hdmi devices, when the HDR10 version it’s true black.

I swear it didn’t used to be like this though. Something changed when LG implemented their HDMI DV “fix”. Like how the opening credits to Mute used to be true black. Maybe something on the mastering/grading side need to change too and just hasn’t caught up yet, but with DV we’ll never know.

I wish people had Panasonic oleds. I’d like to know if they have the same issues.

I wonder if there's an easy way to contact LG about this... I assume they are aware, but maybe not.
 

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So I use a Philips Hue Sync Box between my OLED and my AVR for use with my hue lights which sync with the colors of the content on screen. The box received an updated recently with Dolby Vision support and now the elevated blacks will are gone. The box can be configured with an accompanying app where the user can select how the Dolby Vision content is processed. On the player or on the tv.

Happy to inform that the elevated blacks are gone. The picture is now comparable with the DV in the internal apps of the tv.
 

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Yeah, even if you look at something like the opening credits to Blade runner, the black screen between names is slightly above black with DV with internal apps and hdmi devices, when the HDR10 version it’s true black.



I swear it didn’t used to be like this though. Something changed when LG implemented their HDMI DV “fix”. Like how the opening credits to Mute used to be true black. Maybe something on the mastering/grading side need to change too and just hasn’t caught up yet, but with DV we’ll never know.



I wish people had Panasonic oleds. I’d like to know if they have the same issues.


Blade runner on iTunes shouldn’t be used as a comparison as it’s a faulty encode and exhibits raised blacks on all Dolby Vision sets. This has been the case from its release. Not saying there isn’t a wider issue but that particular release has been widely accepted as being faulty.


Sent from my iPad using Tapatalk Pro
 

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Blade runner on iTunes shouldn’t be used as a comparison as it’s a faulty encode and exhibits raised blacks on all Dolby Vision sets. This has been the case from its release. Not saying there isn’t a wider issue but that particular release has been widely accepted as being faulty.


Sent from my iPad using Tapatalk Pro
I meant the Vudu/MoviesAnywhere version. The intro for those is black, not grey like on iTunes, but there’s still a slight glow in a pitch black room.
 

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What I found is that DV for me appears to have *slightly raised blacks* whether it's through HDMI or the internal apps. This was true whether I was using the calibrated Cinema (user) mode or the stock Cinema Home setting. Also, in general, I found the DV test patterns to be much darker than the HDR10 equivalents. With HDR 10 using the Black Clipping test patterns, I could see almost all gradations above 0%. Easily from 0.9% upwards. With the Dolby Vision test patterns I could only see starting at about 2.7%.


To test for raised blacks I would turn all the lights off and play the Black Clipping 2 test pattern which has a series of bars from 0% to 5%. I would then enter the Brightness control on the TV and move it one notch in each direction, around 48-52. While watching the screen very closely and carefully, in all cases, I could see a tiny amount of brightness emitted from the black background as soon as I went from 49 to 50. This means the panel is not showing 100% black at brightness 50. Brightness 49 "fixes" the problem but exacerbates the black crush issue, meaning I couldn't see any difference in the Black Clipping patterns until about 3.2% or more. I tried messing with OLED light to see if it would offset the issue but it doesn't. Perhaps using Brightness 49 could all be worked out in a finer-grained calibration, really going ham on the 20-point values at the lower end. I'm not sure.
Some of this is also true for my LG C9. See my posts linked below for details.

https://www.avsforum.com/forum/139-display-calibration/3067446-calman-home-lg-84.html#post59636800

https://www.avsforum.com/forum/139-display-calibration/3075780-spears-munsil-uhd-hdr-benchmark-disc-discussion-31.html#post59699132

What I have been experiencing from Dolby Vision with the AppleTV unit via HDMI is a significantly brighter emission of light from what should be black (black bars and black frames) than when viewing the same material from the same programs using the LG C9's AppleTV app.

Also see my post made earlier in thread:

https://www.avsforum.com/forum/40-oled-technology-flat-panels-general/2947164-status-dolby-vision-raised-blacks-issue-oleds-50.html#post59767972

As far as adjusting Brightness to 49 to compensate for slightly raised blacks (occurring both in DV and HDR10 when a custom 1D LUT is used for the picture mode), I have found the Brightness increments far too coarse for the super fine adjustment needed. A 49.99 setting is about what would be needed.

For the "black crush," I've found this to be all over the place depending on which test pattern is used (perhaps because of which Dolby Vision profile was used for the authoring), whether the picture mode is calibrated or not, and whether the USB drive is played directly from the C9, or through my Oppo UDP-203. There's also no guarantee that playing patterns the USB drive either way is equivalent to what happens with Dolby Vision played from a UHD 4k Disc, or from the AppleTV unit.
 

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I meant the Vudu/MoviesAnywhere version. The intro for those is black, not grey like on iTunes, but there’s still a slight glow in a pitch black room.
Using Vudu, what device are you using for external DV test and what device for external HDR-10 test?
 

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Using Vudu, what device are you using for external DV test and what device for external HDR-10 test?

I've used my Shield TV for DV and HDR10, a Roku for HDR10, and an Apple TV for DV.



It's the same thing for Mute on Netflix. Opening is slightly above black in DV over HDMI (a little higher on Apple TV vs the Shield) and pure black with HDR10.
 

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How come professional tv reviewers haven't caught any of this yet? Specifically with the raised blacks with the ATV. They tend to have more of a voice it seems and I would think that some of them have these devices to test. I tried skimming through this thread again and may have missed it but did Apple or LG confirm that a fix was in the works?


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They did years ago when it was really bad. It’s been “fixed” for awhile now even though there’s still problems, and reviewers are always moving on to the new models. DV is broke en on LG’s newest oled TVs, so that will be the focus. Not even sure if it’s an Apple TV problem at this point either.
 

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Well, I don’t see the elevated blacks anymore on the Apple TV 4K. Maybe the latest tvOS update addressed this issue.
 

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Beta or no? I'll take a look. I'm on 13.4.6.

Edit- I still see it with 13.4.6

Sent from my iPhone using Tapatalk

No beta, just the official released version. My C9 OLED also received a firmware upgrade. Maybe it’s a combination of the two.
 

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Well, I don’t see the elevated blacks anymore on the Apple TV 4K. Maybe the latest tvOS update addressed this issue.

I should stress that the raised blacks I'm seeing are only faintly visible in a pitch black room. It's enough to ruin the illusion in this case, but with any ambient light whatsoever it's really not visible.



I think this is partly why the issue isn't talked about more. The issue was "fixed" so it's not as egregious anymore, and some will say that they no longer see it, but it's still there and not just an Apple TV problem.
 

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I should stress that the raised blacks I'm seeing are only faintly visible in a pitch black room. It's enough to ruin the illusion in this case, but with any ambient light whatsoever it's really not visible.
Yes, this exactly. It's subtle. Which is why I think a lot of people declare themselves to be free of it. I really only notice it when a DV movie fades completely to black on the Apple TV for long enough for your eyes to adjust and then notice the faint glow.

I think this is partly why the issue isn't talked about more. The issue was "fixed" so it's not as egregious anymore, and some will say that they no longer see it, but it's still there and not just an Apple TV problem.
I can't speak for other devices, but my nvidia Shield does not exhibit the issue. . . and I know how to look for it, since my Apple TV is affected.
 

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Yes, definitely subtle but it is there. I did do spot checks with my calibration meter and all of the scenes were the same brightness which is encouraging. I compared Dolby Vision on the ATV to the DV Apps on my LG SmartTV and there wasn't any difference in luminance spot checks. I was hoping that the whole picture wasn't brighter and it seems to just affect the pure blacks which is better than I thought (although still not ideal, lol). I couldn't get a read from the black bars that were pure black or raised which is good also and means that it's not horrible, although my meter isn't the highest quality like the ones that the pros have. Again we want them to be absolute black but I don't think anyone should worry about using it normally still.


Sent from my iPhone using Tapatalk
 
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