Movie files play faster on 4k tv than on 1080p. why?

[adacegolf]

Hi!! I have been thinking about into which category I should put this question. So here it comes and sorry if I did not put it into a right category. However, this is a real stunner.

Background: I want to buy a 4K Smart TV. I have chosen LG 65UH600V. Went to a huge local shop to see if anything does not meet my expectations. Clever I took an external hard disk (WD 1,5 TB) with me. I am a huge fan of movies so on the basis of agreement with the shop assistant, I wanted to see how the movies would look like on the screen. The TV should be totally able to play all the MKV's, MP4's and newly even the HEVC codec based movies.
Issue: So I tried it. All the films were playable but THE SPEED OF THE PLAYING was FASTER than it should originally and naturally be. I mean that the movies went on by 1.25 or 1.3 times quicker without any intervention by us.
Background: So I took out the external hard disk and put it into Samsung UE65JU7502, 4K Smart TV as well. The issue came up again. Everybody was amazed but we went on trying in different resolution TVs. What we figured out is that the movies were totally fine with Full HD TVs and movies went flawlessly. However, when the movies were played by any 4K TV. They played faster.
Solution: I spoke to dozens of people who are into TVs and video/audio systems but nobody was able to define the problem and say a hundred percent this is the problem. Maybe, it deals with codecs in the 4K TVs or maybe the up-scalling effect. We don't know.... I am asking for help, please. Thanks guys!

 

[ssddx]

changed your thread title to better reflect your problem so you may get more views from people who may be familiar.

my thoughts?

movies are commonly recorded at 24fps. tvs generally can play at up to 60fps (60hz). generally its not a problem as the tv knows to display it at 24fps but when you throw some of the new technology at things there may be problems.

new tvs often include motionflow and other technologies to make it seem like you're getting a faster response time than the 60fps they are capable of. this can make video wonky and may affect playback of 24fps files. this consists of both adding frames into content and strobing the backlight. part of this is post processing - separate from any upscaling.

try having the store completely disable any and all enhancements of this nature. in other words, run it in game mode or similar. you may notice that this issue goes away.

yet another reason why i think adding all that garbage into tvs is useless.

we run our new samsung and sony with all such modes disabled. luckily my main is older so does not have such trivial features. i've never seen the fastplay issue but do know that motionflow makes everything look fake.

 

[adacegolf]

Thanks for the reaction. You have pointed out a lot to think about, we will try the modes. However, more I think about the issue, more I am convinced it deals with the codecs. Full HD movies encoded in .mkv or .mp4 but 4K TV plays it faster but plays it so the TV somehow can read the file but wrongly. After a discussion with a real expert on video/audio, he claims that it deals with codecs. He says that companies Samsung, LG and so on, they do not care about the customers' needs. They just let you play the true originals, Blue-Rays but no Full HD rips. Just to limit your entertainment and make you buy the originals. That's how it works with the newest models. What do you think about that theory? Thanks!

 

[adacegolf]

Sir! Thanks a lot !!! Your thoghts very right. The issue was based on the TV modes. The "best" they say is the dynamic mode that makes the video faster as it involves many new technologies in playing. So the basic mode makes it play flawlessly. Again, thanks and bless you!