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Question

Judder when changing scenes (LG TV with Truemotion set to of

Feb 19, 2016 7:02AM PST

Hello, maybe you understand what I mean, maybe not, sorry...

I have noticed judder with an LG LF58 TV when watching movies with TrueMotion set to off and there is a scene change (a clear background when the previous was dark for example).
It is like a flash, so I am wondering, does the TV try to interpolate even with TrueMotion set to off sometimes? Maybe when the source is 24fps?

Don't these kind of TVs detect a background change before trying to create interpolated frames?

Discussion is locked

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Answer
Only one way to test.
Feb 19, 2016 10:22AM PST

To see if the TV is doing this I take the playback frame by frame to see if it's in the source.

There are now hundreds of TVs so how they work must be asked of the maker. That is, call them. Here I will share how I figure out if the source is the cause.

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Interpolate when there is not a moving object?
Feb 19, 2016 10:41AM PST

But to inspect the source I should use another device, anyway I don't think it is the source.
My idea of asking was if makers "generally" use some kind of algorithm to recognize a scene change because my guess is it should be avoided to interpolate there when there is not a moving object but a completely different scene.

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I can't answer that.
Feb 19, 2016 10:47AM PST

But I can share how I figure it out. My few players have a frame step feature so when I see an odd jump I can rewind and do a frame by frame. I've lost count of how many discs have built in flaws.

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And have you found such things as I describe?
Feb 19, 2016 10:51AM PST

Have you found something similar to what I describe (or try to) in Netflix movies?

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Yes. But how I know?
Feb 19, 2016 3:15PM PST

Because my TV is an older 60Hz model it can't do any motion smoothing. Netflix does heavy video compression so it's inferior to say BluRay releases. Can cause folk that are used to content on cable or BluRay to write what you have above.

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This fellow with a Sony here has the same issue and recorded
Feb 22, 2016 10:18AM PST
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This may upset you.
Feb 22, 2016 10:34AM PST

But the video there was when the menu was up and the CPU+GPU are going to mess up. Too bad it wasn't with normal display only. I've seen the displays goof when the menu is up and for reasons I can't write here, it's not going to be fixed.

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yes
Feb 23, 2016 4:09AM PST

the effect is exactly the same but without the menu, my LG is new, I bought it this month but LG is not present in my Country, only in the neighbor Country of Argentina, here there is a technical service by contract and they say they are just a service, not LG nothing they can do as a service.

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Then you make it the "unfit for purpose" return.
Feb 23, 2016 9:49AM PST

Now that it's not acceptable you drop all pretense that it's acceptable and start the return process. If other sets work, you want a working set.

I know folk that exchange sets and see the same glitch on content which we know is in the source but they exchange anyway. The highest number of exchanges I've heard of is about 12. Never heard what was the end story. My bet is they hate HDTV.