Apple TV 4K problem with Dolby Vision

Thank you for posting here in Apple Support Communities, Sciletto.

We can definitely see the difference in image quality within both photos, and we'd be happy to help. To start, we'd recommend that you check out the information along with the troubleshooting steps within the following resource: About 4K, HDR, and Dolby Vision on your Apple TV 4K

We should also check for any available updates for the tvOS as well. Here's how: How to update your Apple TV

Keep the community posted on the results.

Cheers!

same here with LG sm8600. Dolby Vision quality in Netflix is much better with native app of the tv or Xbox one X

using belkin recommend cable and ATV is connected directly to TV

all settings are in placed and correct set

thanks for your reply but did not work.

the only thing that works is the following

set ATV to Dolby vision all the time and match frame rate / dynamic range to on

so in Netflix DV shows are as good as with native app or Xbox one

seems to be an issue when changing from SDR to DV

keep in mind that the issue is only happening in Netflix app

with ATV+ all works ok - having ATV to SDR or DV all the time with frame rate / match dynamic range to on

This is an issue with Apple TV. It’s been known for a long time but recently confirmed by someone on AVS forums. Please see the link and analysis here: https://www.avsforum.com/threads/2020-lg-oled-cx-gx-owners-thread-faq-posts-1-6-no-price-talk.3119288/page-854#post-60359866

Can we please get this escalated and fixed. It is the only thing holding me and a lot of people from using the ATV and it’s a horrible issue that defeats the purpose of all this high end content and equipment. It’s really a shame how long this issue has gone unacknowledged by Apple.

Enabling DV is not the issue. That should be in the settings or you can put match content on to auto switch. We are talking about raised black levels specifically on Dolby Vision on OLEDs via ATV due to ATV incorrect color output.

I may have some good news here. I bought the new 2021 Apple TV 4K and can confirm I have no more raised black levels in Dolby Vision. I own a LG C9 and have been having the raised blacks issue from the beginning; it’s gone now. Obviously it’s not the ideal solution because it requires purchasing a new product, but I’m just letting you know it seems to have been fixed with the new model. Hope this helped someone!

Definitely. I’ve tested a lot of movies now just to make sure — on multiple apps. I got a little scared when I tested Zack Snyder’s new movie on Netflix, Army of the Dead, because it shows slightly elevated blacks at the very beginning, but that turned out to just be the movie itself; it also looks that way on the C9’s internal Netflix app. So, based on what I’ve tested so far, it appears to be fixed. Maybe the fact that it’s a HDMI 2.1 device and requires a ultra high speed cable has made the difference, or maybe Apple has simply fixed it — I’m not sure.

@sciletto,

It sounds like to me that the AppleTV is sending the DV data in its RGB 8 bit wrapper as it should, but either the ATV or the TV isn’t properly decoding the Full RGB 0-1023 video levels (normally used for PC signals) to the RGB 64-940 Limited video levels (normally used for video signals) as it is supposed to. This would result in the hazy, raised blacks you report.

The DV processing uses the Full 0-1023, 10 bit range, but it’s supposed to change it for display in the final stage to Limited 64-940 video range because that’s what Home Video displays are designed for. Since the Dolby processing happens in the TV when DV is sent as RGB 8 bit, as opposed to when it sends LLDV’s YUV 10-12 bit, then it appears the LG TV is at fault actually for not decoding the full DV signal properly. It could be something missing in the AppleTV’s DV output as well I guess, in which maybe it doesn’t signal the LG TV to go into Limited Mode for display, idk.

You can try this yourself with other input signals if your TV has the option to switch from Full to Limited video signals. If you test by watching the same scene with something like the Bluray or an SDR version of the film, try changing from RGB Limited to Full and back and you’ll see the same anomaly.

I have the same problem.

I've tried everything (changed cable, changed TV and Apple TV settings) and nothing worked.

If you turn Dolby Vision off, the image get better.

I just have the Apple TV 4K 2021 connected with HDMI (the one in the photo) to my LG C9, and that’s it. :)