24fps on 100Hz LCD TVs - I'm confused!

Jeff B

Active Member
Hi,

hope this is in the right sub-forum. Here goes!

I've been looking round for a new LCD TV after my old one died, and want one that displays 24 fps 1080p. I understand everything I've read on the subject apart from how the pulldown applies to 100 Hz TVs in the UK.

Many 24fps-capable TVs on sale say they apply a 5:5 pulldown to the image. The explanation that usually follows is that each frame is displayed five times and 5 x 24 = 120. So far, so good!

How does this apply to 100 Hz televisions? I thought 120 Hz TVs were for the US market, and while I can see that a 5:5 pulldown gives 120 HZ for a US TV I cannot see how it gives 100 Hz for a UK one.

Can somebody please explain? I have trawled the internet trying to find out, but all the explanations seem geared to 120 Hz TVs, not 100 Hz ones.

Also, do some TVs give you the option of using a pulldown to reduce judder, or watching 24 fps, judder and all? Thanks :)
 

J4CK DANIELS

Novice Member
this is my (brief) take on it all....

100Hz for a 50Hz broadcast signal is all about whacking in an extra frame to make it up to 100Hz at the video chipset stage.

I 'ASSUME' the actual LCD modules (not the video chipset) can be driven to a MAX of 120Hz (even outside the U.states) so the 5:5 can still apply on EU models.....

(just what i 'heard' maybe someone else can confirm or deny? That's for LCD, PDP could be different and Pioneer being the only ones that can drive the module at a native 24fps)
 

Jeff B

Active Member
Turn of the 100hz when watching blu ray at 24p, little point using the tech to add extra frames when its not needed?

Ah! So there's an option to turn it off? In that case I assume the T.V. would play at 24 fps or a multiple thereof? Can 100Hz TVs play at, for example, 96 Hz if needed?

@Hyperboy

Thanks! I thought that would be the case for broadcast signals, but was wondering about blu-ray, as I'm sure you guessed! :) I hadn't even come round to thinking about chipsets yet. Only Pioneer models can do an actual 24 fps?
 

Restorer

Well-known Member
Hi,

hope this is in the right sub-forum. Here goes!

I've been looking round for a new LCD TV after my old one died, and want one that displays 24 fps 1080p. I understand everything I've read on the subject apart from how the pulldown applies to 100 Hz TVs in the UK.

Many 24fps-capable TVs on sale say they apply a 5:5 pulldown to the image. The explanation that usually follows is that each frame is displayed five times and 5 x 24 = 120. So far, so good!

How does this apply to 100 Hz televisions? I thought 120 Hz TVs were for the US market, and while I can see that a 5:5 pulldown gives 120 HZ for a US TV I cannot see how it gives 100 Hz for a UK one.

Can somebody please explain? I have trawled the internet trying to find out, but all the explanations seem geared to 120 Hz TVs, not 100 Hz ones.

Also, do some TVs give you the option of using a pulldown to reduce judder, or watching 24 fps, judder and all? Thanks :)

As I understand, it all of our so called 100Hz TVs are actually 120Hz sets which also display at 100Hz depending on what signals they are being fed :).
 

Jeff B

Active Member
As I understand, it all of our so called 100Hz TVs are actually 120Hz sets which also display at 100Hz depending on what signals they are being fed :).

That's news to me! It would make a great deal more sense. A shame that they aren't called 120/100 Hz televisions then!

Do you happen to know if the 5:5 pulldown can be turned off to view just 24fps? I know it might be a bit flickery, but I always like to have the option to fiddle with settings, even if the machine knows better - know what I mean? :)

One thing I do find frustrating is that online technical specifications for TVs can be a bit vague and it's hard to see what you are buying, especially on Amazon, which is probably where I'll end up buying my new set.
 

Nielo TM

Distinguished Member
Hi,

hope this is in the right sub-forum. Here goes!

I've been looking round for a new LCD TV after my old one died, and want one that displays 24 fps 1080p. I understand everything I've read on the subject apart from how the pulldown applies to 100 Hz TVs in the UK.

Many 24fps-capable TVs on sale say they apply a 5:5 pulldown to the image. The explanation that usually follows is that each frame is displayed five times and 5 x 24 = 120. So far, so good!

How does this apply to 100 Hz televisions? I thought 120 Hz TVs were for the US market, and while I can see that a 5:5 pulldown gives 120 HZ for a US TV I cannot see how it gives 100 Hz for a UK one.

Can somebody please explain? I have trawled the internet trying to find out, but all the explanations seem geared to 120 Hz TVs, not 100 Hz ones.

Also, do some TVs give you the option of using a pulldown to reduce judder, or watching 24 fps, judder and all? Thanks :)

The UK 100Hz sets are also compatible with 120Hz. By that I mean they will accept 60Hz and display it at 120Hz via MCFI.

Some UK sets indeed apply 5:5 pull-down (120Hz), but others simply switch to a frequency that is multiple of 24 (48, 72, 96).


PS: At the end of the day, 24p performance vary from model to model. So do you have a particular model in mind?
 

Restorer

Well-known Member
Some UK sets indeed apply 5:5 pull-down (120Hz), but others simply switch to a frequency that is multiple of 24 (48, 72, 96).

Neilo, is there a list somewhere of how sets handle this? Pretty sure my Sony 40W4500 for example is one that does 120Hz.

Does it depend on manufacturer or individual models? Is it safe to say if the set has Motionflow or the equivalent then it will be able to apply 5:5 pulldown and what happens if Motionflow is set to off? Does it have to be ON for it to do 120Hz via interpolation?
 

J4CK DANIELS

Novice Member
Don't some older TV's do a 3:2 pulldown and then double it up to get the 120Hz?...
 

Jeff B

Active Member
The UK 100Hz sets are also compatible with 120Hz. By that I mean they will accept 60Hz and display it at 120Hz via MCFI.

Some UK sets indeed apply 5:5 pull-down (120Hz), but others simply switch to a frequency that is multiple of 24 (48, 72, 96).

PS: At the end of the day, 24p performance vary from model to model. So do you have a particular model in mind?

Thank you, Nielo! That's very useful information. :thumbsup:

I was thinking of the Toshiba 37RV555DB 37-inch model that I saw on Amazon. I would be very grateful if you could give me some advice on this model. If it does not have the capabilities we've been discussing, could you recommend one of a similar size and in a similar price range?

I'm also interested in hearing the answer to Restorer's questions. Thank you to everybody who has replied: this is really helpful, as I simply could not find answers anywhere else. :)
 

MartiB

Standard Member
Sony sets with 24p True Cinema will automatically disable Motionflow if a 24p frame rate is detected, according to the Sony web site.
 

Nielo TM

Distinguished Member
Neilo, is there a list somewhere of how sets handle this? Pretty sure my Sony 40W4500 for example is one that does 120Hz.
As far as I'm aware, there's no such list.

Does it depend on manufacturer or individual models?

It varies from manufacture to manufacture and model to model

Is it safe to say if the set has Motionflow or the equivalent then it will be able to apply 5:5 pulldown and what happens if Motionflow is set to off? Does it have to be ON for it to do 120Hz via interpolation?

No. Motion flow simply enables/disables low-level and high-level MCFI. So for movies and seasonal programs, it should be disabled.

When 24p is detected, the TV should switch to a compatible display frequency automatacally. Otherwise, you'll notice telecine judder
 

Nielo TM

Distinguished Member
Thank you, Nielo! That's very useful information. :thumbsup:

I was thinking of the Toshiba 37RV555DB 37-inch model that I saw on Amazon. I would be very grateful if you could give me some advice on this model. If it does not have the capabilities we've been discussing, could you recommend one of a similar size and in a similar price range?

I'm also interested in hearing the answer to Restorer's questions. Thank you to everybody who has replied: this is really helpful, as I simply could not find answers anywhere else. :)

Toshiba sets are known to use 5:5 pull-down, but I can't confirm on their performance.



If you're an serious/hard-core gamer, I recommend the Panasonic S10

Panasonic TX-L37S10B 37-inch Widescreen Full HD 1080p: Amazon.co.uk: Electronics & Photo


But if you're a casual gamer, I recommend the following

Samsung LE40B650T2 40" 1080P Full HD Crystal LCD TV: Amazon.co.uk: Electronics & Photo

Samsung LE37B650T2 37" 1080P Full HD Crystal LCD TV: Amazon.co.uk: Electronics & Photo

PS: The 40" Samsung B650 has better panel than the 37B650 .
 

Jeff B

Active Member
If you're an serious/hard-core gamer, I recommend the Panasonic S10

Panasonic TX-L37S10B 37-inch Widescreen Full HD 1080p: Amazon.co.uk: Electronics & Photo


But if you're a casual gamer, I recommend the following

Samsung LE40B650T2 40" 1080P Full HD Crystal LCD TV: Amazon.co.uk: Electronics & Photo

Samsung LE37B650T2 37" 1080P Full HD Crystal LCD TV: Amazon.co.uk: Electronics & Photo

PS: The 40" Samsung B650 has better panel than the 37B650 .

Thanks for the recommendations. In fact, I'm not really a gamer at all: I'm in to films. I just need a new TV that will work like a dream at 24 fps when I buy a blu-ray player.

Actually, according to the descriptions in Amazon, none of these examples seem to display 24 fps. :confused: Is this Amazon failing to accurately describe their products again? I've had many problems with this in the past, so it wouldn't surprise me.

P.S. It's a shame your HD TV guide's not up and running at the moment. It would definitely help!
 
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Nielo TM

Distinguished Member
the guide is seriously outdated lol

And yes, Amazon's product description are flawed. That's why you should check the manufactures web site.

Anyway, since you're not a gamer, go with the 40B650 I've linked to.
 

Jeff B

Active Member
the guide is seriously outdated lol

And yes, Amazon's product description are flawed. That's why you should check the manufactures web site.

Anyway, since you're not a gamer, go with the 40B650 I've linked to.

Thank you very much! I pretty much have what I need to know now, so the rest's up to me. I've slight reservations about the reliability of Samsung TVs, but I'll give serious thought to the Panasonic you recommended. Thanks again for helping a newb out. :)
 

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