I have an LG OLED55C6P 55" 3D TV (passive 3D technology), a Roku 4, and a gigantic collection of digital (mp4) 3D movies which I cannot enjoy unless I watch them directly from my flash drive. Part of why I bought the Plex Pass was because I read that Plex supports the 3D format, so I definitely feel like I’ve been a victim of bait and switch.
The TV does present me 3D mode as an option, but the signal from the Plex server is formatted incorrectly, so the resulting aspect ratio is 32:9. There is surely some small rendering detail in each frame that the TV is looking for which is being suppressed by the Plex software, so the TV just displays both left/right images side by side instead of interlacing them every other frame as 3D should be. I have put H-SBS at the end of every filename as instructed by Plex. I have tried all possible aspect ratios (zooming, no zooming, standard, 16:9, etc.) on the TV. The problem persists. It is pretty obvious that the TV is not at fault since any given file plays just fine from a flash drive plugged directly into the TV, while the exact same file plays incorrectly when Plex is transmitting it to the TV.
For additional information (and corroboration from other users!), please see:
Plex, please realize how important this is to the 3D community. It also seems to me that this isn’t really a feature request - it’s really a bug that prevents Plex from living up to what the Plex website claims it does, and with that, it seems to me this should be a really high priority. You shouldn’t be adding additional bells and whistles to Plex until the bells and whistles you have already advertised are fixed.
Taken directly from the official Plex website:
“Is 3D playback supported?”
“Yes. However, note that there is nothing special that the Plex app can do to instruct the television that a specific video is 3D. You will need to enable the appropriate 3D viewing mode on the television yourself.”
I’ve enabled the appropriate 3D viewing mode on my television myself, I’ve put H-SBS into the filename, and still it doesn’t work for anyone with my model.
I spent good money on a lifetime Plex Pass largely for this feature, so the failure to support it has been extremely disappointing.