600Hz, let's get it sorted

Monarch

Distinguished Member
Joined
Dec 8, 2008
Messages
8,647
Reaction score
1,143
Points
1,271
Location
The North
Hi all,

Right! As we all know some of the new models from LG and Panasonic (and Samsung?) have 600Hz technology built in but contrary to belief among some this is not the same as 100Hz, there are various theories floating around as to what exactly it does, can someone, with a decent source, please enlighten us all (in detail) as to what it is and does? This is confusing a lot of people so it should be sorted

cheers
 
The way i understand it is that 600hz is better than 100hz !!!! as it says in all the specs i have read with regards to Scanning, here is what it said on dixons site:-
The stylish LG 42PQ6000 42" HD Ready Plasma TV features 600Hz Sub-field Driving technology to produce a picture with fantastic clarity and minimal blur. It also features a stunning 2,000,000:1 dynamic contrast ratio, and 16-bit RGB colour depth, to deliver you a picture with incredible realism and deep, rich tones and colours.
 
I reckon its at least 6 times better than 100Hz :devil:
 
In last year's training material sets were described with either 400Hz or 600Hz sub field drive (can't remember which) and these were advertised to the public as 100Hz. So what's changed?

The training material seemed to state that it allowed the television to produce a 60Hz image from a 50Hz source without judder.
 
I've done a little bit of searching and still can't seem to find a definitive answer, all that I've found are ageing techies on various websites stating what they read once. I've read that it's the only number which divides equally into all of the main 'Hz's' used (24/50/60 etc...) but a 600Hz sub field drive isn't the same as 100Hz picture display. I've also seen mentioned that it basically displays in 100Hz, but each frame is flashed 6 times, leading to 600 'flashes' but overall just 100Hz in terms of the frames being displayed, this also links in the IFC on the Panasonics and things which are included in the package and does make sense. I've also seen written that it's just the processing which is done in 600Hz, but the display is still 100Hz. How this would work I'm unsure.

I'm going to try and get some info off the companies themselves, although the customer support people never know anything, it's worth a try :rolleyes:
 
I've done a little bit of searching and still can't seem to find a definitive answer, all that I've found are ageing techies on various websites stating what they read once. I've read that it's the only number which divides equally into all of the main 'Hz's' used (24/50/60 etc...) but a 600Hz sub field drive isn't the same as 100Hz picture display.

Correct, it isn't.

I've also seen mentioned that it basically displays in 100Hz, but each frame is flashed 6 times, leading to 600 'flashes' but overall just 100Hz in terms of the frames being displayed,

Incorrect. There is no 'flashing' of extra frames. In 100Hz mode a tv displays 100 images per second, in 60Hz mode it displays just 60. I also saw this 'flashing' theory and asked the poster for his source on this and got no reply.

this also links in the IFC on the Panasonics and things which are included in the package and does make sense. I've also seen written that it's just the processing which is done in 600Hz, but the display is still 100Hz. How this would work I'm unsure.

Correct. Using Panasonic as an example, it is the processing which is done at 600Hz. From the original 24/50/60 frames, the tv's processor creates 600 frames using interpolation. This new super smooth video stream is then displayed on the screen at 60Hz by displaying every 10th frame from the new, smoother video.


I'm going to try and get some info off the companies themselves, although the customer support people never know anything, it's worth a try :rolleyes:

Last year's Panasonic plasma sets with IFC worked in exactly the same way (although the process has been refined this year) it is just that with the advent of 200Hz LCD sets, the marketing dept felt that '600 Hz' would be an eye-catching spec.
 
Isn't this something more to do with Plasma vs LCD?... LCD uses frame and hold and plasma by it's very nature HAS to flash more often to keep the pixel lit....

* If an LCD show's an image of pure white it simply leaves the pixels 'open' to let the light through

* For a Plasma, even if the image is static and the same as the last frame it still has to flash

Is that right?...

I fear this is Plasma's Marketing way of 'competing' with 100/200Hz for LCD (which in turn was trying to lever the old days of the trinitron 100Hz CRT which DID make a difference then!! (without any adverse speeding up effects etc...)
 
Last edited:
Well the 600Hz sub field on the plasmas isn't the same thing as 100Hz/200Hz on LCDs (and it's not the same as 100Hz on plasma). 100Hz on plasma TVs is pretty much standard now, but it's used to reduce flicker as opposed to motion blurring as it's used on LCDs.

The reasoning behind me making this thread was that people were getting caught up in 600Hz being a feature like 100Hz or 200Hz on LCDs. 600Hz obviously sounds better, but it's not the same thing, I could say that to people but could never explain it. I had put alsinas description as my 'favoured' theory after a bit of jiggling about with various things I've read on the subject.
 
Well the 600Hz sub field on the plasmas isn't the same thing as 100Hz/200Hz on LCDs (and it's not the same as 100Hz on plasma). 100Hz on plasma TVs is pretty much standard now, but it's used to reduce flicker as opposed to motion blurring as it's used on LCDs.

The reasoning behind me making this thread was that people were getting caught up in 600Hz being a feature like 100Hz or 200Hz on LCDs. 600Hz obviously sounds better, but it's not the same thing, I could say that to people but could never explain it. I had put alsinas description as my 'favoured' theory after a bit of jiggling about with various things I've read on the subject.

Its not a theory, it's part of our training from Panasonic. I'm looking to get something I can post as an attachment soon.
 
Its not a theory, it's part of our training from Panasonic. I'm looking to get something I can post as an attachment soon.

I'm not questionning your description, I was referring to it being a theory in my own mind which hadn't been confirmed by anyone reliable, now you have confirmed it though :thumbsup:
 
I did some tests of the AV sync on my panny TH42PZ80 a while back.

It used a photodiode to look at the sync lines in the BBC testcard.

See here BBC - BBC Internet Blog: A Christmas Present from the HD Channel!

Now if you look at this picture of the result you will see the sync line appears actually to be pulsed 24 times in 40 ms (1 frame), or 600 times a second.

Picasa Web Albums - BBC HD sound ...

The blurb on the plasma states its 100Hz. It doesn't feature intelligent frame creation.

So I can only conclude it may fire the phosphers 600 times a second but still only displays 100 (repeated) frames second.
 
Last edited:
The reasoning behind me making this thread was that people were getting caught up in 600Hz being a feature like 100Hz or 200Hz on LCDs. 600Hz obviously sounds better, but it's not the same thing,
So what is it then?:confused::boring:

I always thought Sony 200hz and the other 100hz guys were so behind with their tech? I've just seen on TV that Panasonic 600/100hz ad and people must be buying it instead of the sonys which have a very low HZ:confused::lesson:
I'm quite happy with my 100HZ. Don't need 6 more:rotfl:
 
Well we will hopefully get it sorted once and for all, I'll be listening to the podcast when it arrives (when will it be up?) and I might contact LG and Panasonic later on.

Basically my vague understanding of the basics behind it is that 100Hz (on plasma) reduces flicker, 600Hz makes motion smoother
 
Well we will hopefully get it sorted once and for all, I'll be listening to the podcast when it arrives (when will it be up?) and I might contact LG and Panasonic later on
Sorry about the silly question, but what's a Podcast? I don't have an I Pod:confused: so i don't think i can listen or watch it:boring::(
 
I did some tests of the AV sync on my panny TH42PZ80 a while back.

It used a photodiode to look at the sync lines in the BBC testcard.

See here BBC - BBC Internet Blog: A Christmas Present from the HD Channel!

Now if you look at this picture of the result you will see the sync line appears actually to be pulsed 24 times in 40 ms (1 frame), or 600 times a second.

Picasa Web Albums - BBC HD sound ...

The blurb on the plasma states its 100Hz. It doesn't feature intelligent frame creation.

So I can only conclude it may fire the phosphers 600 times a second but still only displays 100 (repeated) frames second.

Well if this is true, then yours is the only PZ80 that does.

Last year's IFC (480Hz):
 

Attachments

  • IFC2008.jpg
    IFC2008.jpg
    92.1 KB · Views: 2,643
Well if this is true, then yours is the only PZ80 that does.

Last year's IFC (480Hz):

that makes perfect sense to me :thumbsup:

and Tvbox, I know what a podcast is but I don't really know how to describe it...it's like a downloadable radio show (to the extent that I know them anyway), you don't need an iPod to listen to them
 
It doesn't have IFC

I realise that. I was just pointing out that other than IFC, there is no mention anywhere else of anything more than 100Hz on last year's range, but where there is (IFC), the technology is clearly documented and shows that with 480Hz sub field drive, the tv is still only refreshing at 60Hz. As interesting as your test is, I don't think it tells us anything relevant to this thread.
 
I realise that. I was just pointing out that other than IFC, there is no mention anywhere else of anything more than 100Hz on last year's range, but where there is (IFC), the technology is clearly documented and shows that with 480Hz sub field drive, the tv is still only refreshing at 60Hz. As interesting as your test is, I don't think it tells us anything relevant to this thread.

Yes, what I observed could just be the PWM. Your diagram explains the IFC sub field drive nicely:thumbsup:

I wonder what directors, who deliberatly use film or 25psf video because of it's temporal presentation/look make of these IFC/motionflow tvs? Isn't everything going to start looking very different from the original artistic intention? Like video?
 
Last edited:
So, to clarify exactly what alsina is saying, which would go along with the training material, is that the TV runs at 100Hz as normal to reduce flicker until IFC is turned on, at which point it processes 480Hz worth of interpolated frames to produce a 60Hz image from 50Hz (for last year and S10) or 720Hz to produce a 120Hz image from 50Hz (for G10, V10 and Z1).

Presumably they're advertising this as 400 and 600Hz subfield drive respectively because the European market expects to see a frequency which has a factor of 50. Either that or it's not working in quite the same way as last year, and more like standard interpolation?

My only problem is that that seems ludicrously over complex processing compared to other motion interpolation for little, if any, gain over such technologies (other than the ability to tout it on the spec sheet, I guess. Though a cynic would say the same about 200hz over 100..)
 
I think that's basically what's happening, it sounds complex but it does seem to work, even if the difference isn't as big as you might expect with the number 600 :rotfl:
 
So..... (I think) we've got it sorted then and know what it IS.... BUT.... does it actually make any difference!?!?.... i've seen it on the LG Plasmas and i can't tell any difference!! (i don't think you can even turn it on and off can you?) does it have any adverse affects (like 100 and 200Hz for LCD's) or is it just another silly number like contrast ratios!!? :suicide:
 
So..... (I think) we've got it sorted then and know what it IS.... BUT.... does it actually make any difference!?!?.... i've seen it on the LG Plasmas and i can't tell any difference!! (i don't think you can even turn it on and off can you?) does it have any adverse affects (like 100 and 200Hz for LCD's) or is it just another silly number like contrast ratios!!? :suicide:

There are fewer side effects as the steps between the 600 frames are smaller. Panasonic as an example apply the effect mildly in their 2009 sets after a disasterous implementation on their 2008 sets. The aim is to smooth motion without destroying picture quality.
 

The latest video from AVForums

TV Buying Guide - Which TV Is Best For You?
Subscribe to our YouTube channel
Back
Top Bottom