LG CX frame rate not matching

OldSkoO1

Active Member
I’m thrilled with the new LG CX. I also purchased a Denon x3700h. Connected to this is an Apple TV 4K.

I’m running Apple TV at 4K SDR 50hz

My issue is that when using the internal diagnostics menu (channel tuning highlight and pressing 11111) it’s saying I’m running at 50hz

I can already see the occasional judder.

I’m testing using a Netflix test pattern video which displays at 24hz

Any ideas why the LG isn’t recognising the correct frame rate ?

I only have match range on Apple TV, match rate seems to give lip sync issues. Plus I believe most modern TVs can decode the true frame rate.

If it’s not the tv, maybe the amp is fixing the frame rate output?

Thanks
 
Movie sources for Blu-ray discs and streaming services are encoded at 23.976fps/Hz or 24.000fps/Hz, not 25.000fps/Hz or 50Hz.

EDIT: The only exception is the UK based service Now TV (recently renamed to just NOW), which was forced to offer real-time/live streamed content (due to Ofcom regulations) at 25.000fps or even 50.000fps 25Hz/50Hz.

If your AppleTV device offers it, it needs to configured to match the sources frame/refresh-rate...
 
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OldSkoO1

Active Member
I switched on frame matching now. It has indeed picked the correct rate now. Strange as I thought TVs auto did this by analysing the source signal

anyhow, I’ve realised that previously, running a fixed 50hz my audio delay setting compensated adequately.

Now with variable refresh rates, mainly 24 and 50, I needed to adjust this to an average value.

Amazon however is a mess and needs more delay. Not much I can do about this.

Such a shame that different frame rates and resolutions have different delays.
 

AVPup84

Novice Member
Does anyone know whether real cinema feature is on by default on filmmaker mode? Reason I’m asking I occasionally notice skip frames when watching 4K discs 24fps. All most all these discs are brand new and if I go back to that same scene it plays perfect. No one else notices these small skips (probably a single frame) apart from me and it’s driving me bonkers!!
 
Does anyone know whether real cinema feature is on by default on filmmaker mode? Reason I’m asking I occasionally notice skip frames when watching 4K discs 24fps. All most all these discs are brand new and if I go back to that same scene it plays perfect.
What make and model of 4K UHD player do you have? And is it 'directly connected' to your TV or being passed through an AVR?

While playing your discs, you could check your TV's settings to see if the 'Real Cinema' option is enabled - If you haven't done so already!

That being said... I've also started seeing the same issue when viewing various 4K UHD content via the Disney and Amazon apps on my 2016 LG 65UH770V (after a recent software update) - But not on my 2016 LG 43UH668V.

Viewing my 4K UHD disc (.mkv) back-ups using the TV's 'Photo and Video app seems okay though. (I'm yet to check my OPPO)

By-the-way (and for the sake of accuracy), the vast majority of 2K and 4K Blu-ray disc sources have video encoded at 23.976fps (not 24.00fps), which should be displayed by the TV at 23.976Hz. But if the TV displays 23.976fps encoded content at 24.000Hz you will see a stutter every 41/42 seconds (as the time difference between 23.976 and 24.000 is 0.024).

Similarly, if the TV displays 24.000fps encoded content at 23.976Hz you see a stutter also!

All the above was first noticed years ago, after TV and Blu-ray player manufacturers were highly promoting 24Hz products!
 

AVPup84

Novice Member
What make and model of 4K UHD player do you have? And is it 'directly connected' to your TV or being passed through an AVR?

While playing your discs, you could check your TV's settings to see if the 'Real Cinema' option is enabled - If you haven't done so already!

That being said... I've also started seeing the same issue when viewing various 4K UHD content via the Disney and Amazon apps on my 2016 LG 65UH770V (after a recent software update) - But not on my 2016 LG 43UH668V.

Viewing my 4K UHD disc (.mkv) back-ups using the TV's 'Photo and Video app seems okay though. (I'm yet to check my OPPO)

By-the-way (and for the sake of accuracy), the vast majority of 2K and 4K Blu-ray disc sources have video encoded at 23.976fps (not 24.00fps), which should be displayed by the TV at 23.976Hz. But if the TV displays 23.976fps encoded content at 24.000Hz you will see a stutter every 41/42 seconds (as the time difference between 23.976 and 24.000 is 0.024).

Similarly, if the TV displays 24.000fps encoded content at 23.976Hz you see a stutter also!

All the above was first noticed years ago, after TV and Blu-ray player manufacturers were highly promoting 24Hz products!
It’s CX and going through my denon x8500h. I’m using a Panasonic UB9000. I only ever notice once during a movie for quick second or so but not on every movie though. No issues with audio so it’s not skipping. It’s almost like the frame jumps by a second and it’s fine afterwards. Also I can’t then never recreate it on that same scene again!
Just wondering whether real cinema is default on or off on filmmaker mode
 
It’s CX and going through my denon x8500h. I’m using a Panasonic UB9000.
Make sure your Denon is not performing any type of video processing (which all AVR's do by default). And also make sure your Panasonic isn't forcing 24Hz images.

As a cross check, try temporarily connecting your Panasonic 4K UHD player directly to your TV. ie: by-passing your Denon.
Also I can’t then never recreate it on that same scene again!
You wont see it occur again within the same scene because after rewinding you start off at a totally different time point.
 

AVPup84

Novice Member
Make sure your Denon is not performing any type of video processing (which all AVR's do by default). And also make sure your Panasonic isn't forcing 24Hz images.

As a cross check, try temporarily connecting your Panasonic 4K UHD player directly to your TV. ie: by-passing your Denon.

You wont see it occur again within the same scene because after rewinding you start off at a totally different time point.
Thanks
 

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