50 replies to this topic

[optusman]

There is a new LCD in town for sport and it is definitely the LT-Z37DX5 with their 'clear motion' system.
Thanks to Beardse from another thread for putting me on to this.

Got to see an array of TV's this afternoon, and here is my summary:

The Toshiba, Philips, Samsung were way too bright, no depth in colours, no detail in contrast and struggled with the fast motion.
* The Bravia ALSO STRUGGLED with the camera panining, zooming and following the general flight of the ball but was sharper and better than the rest
* The JVC for sport WAS FANTASTIC. No motion blur, you could follow the ball just like a CRT. The JVC rep told HN that it is 6ms black to white as opposed to 8ms grey to grey for Sony. I researched this on a European website (italy) and they claim the same. The picture has depth, the colours have depth. It is not as bright as the other sets (on 50% brightness, but who knows if the others were on 100%) but contrast detail good. The only bugbear is that i'ts not as sharp a picture as the Sony but that is a compromise I'd be willing to make.

In short, for gaming and DVD's, I'd go the sony. For sport go the JVC.

Has anyone else got/reviewed this model ?  
Also, is your picture sharp when you took it home (ie no digital noise/interference)

[Drizt]

What price were they doing it for ?

[Junkyard]

sorry but if you think if you can actually see a difference betwwen 6ms and 8ms you got problems

[madmax]

Why not? It's 25% faster, and possibly measured using a different standard (i.e. black to black). Have you seen one? Maybe you should before you criticise.......

[fobfob]

optusman, on May 13 2006, 05:30 PM, said:

The JVC rep told HN that it is 6ms black to white as opposed to 8ms grey to grey for Sony.

In that case it is almost certainly slower than the Sony, assuming you can believe the specs.

Black to white is a faster transition than grey to grey. The reason they quote grey to grey (GTG) figures is because that is the slowest (worse case) transition. In other words, the figure you should be looking for is the GTG.

Of course you could argue that all you care about is white to black because most fast motion that you care about is high contrast. However I suspect the BTW and GTG figures are in proportion.

You can also argue that the Sony is much worse than it's specs, as has been seen in at least one test available online (needs a google).

But the best argument is that it looks better to your (his?) eyes. Therefore, buy it!

madmax, on May 15 2006, 04:54 PM, said:

Why not? It's 25% faster, and possibly measured using a different standard (i.e. black to black). Have you seen one? Maybe you should before you criticise.......

Oops. Well I'll help. Forgetting the measurement "standard" for a minute, 8ms equates to 125 frames per second. This is faster than the eye can see and much faster than the picture content is being updated (DVB signal at 50Hz interlaced == 50 fields per second).

So at 8ms, assuming it's really 8ms, you're already faster than it needs to be for anything other than insane gaming.

Going to 6ms means 167 frames per second. nuff said!

Hint: movies are 24 frames per second!!

[madmax]

With that logic, everyone should have been happy with 16ms = 62.5 fps. But they weren't. Clearly there is a lot more to it than that.

[Ajax9000]

madmax, on May 15 2006, 05:07 PM, said:

With that logic, everyone should have been happy with 16ms = 62.5 fps. But they weren't. Clearly there is a lot more to it than that.

Depending on their eyes, source material (e.g. image moving or not, high/low contrast, colour), ambient conditions, etc. most people will stop noticing any refresh artifacts somewhere between 50 and 90Hz.

e.g.

Google "Critical flicker frequency".

Adrian

[fobfob]

madmax, on May 15 2006, 05:07 PM, said:

With that logic, everyone should have been happy with 16ms = 62.5 fps. But they weren't. Clearly there is a lot more to it than that.

Agreed. Basically, either the response time specs quoted by all LCD manufacturers are total BS, or the problems people are seeing have nothing to do with response times.

IMO image processing techniques account for much of the PQ that people see. The signal must be decoded, interlaced, scaled, and other optional techniques such as colour and noise filters applied, before finally being displayed.

Without reverse engineering the design it's pretty hard for us armchair critics to quantifiably judge the relative merits of each product. Even if you are able to find out the specs of the image processing chipset, who knows if the implementation is correct, without looking at the circuit design?

In the end, your eyes are the best tool. The only problem is that it is hard to find a retailer that can provide a objective and representative test environment in which to compare products. Even if they did, your results may vary when you get it home....

[Drizt]

madmax, on May 15 2006, 05:07 PM, said:

With that logic, everyone should have been happy with 16ms = 62.5 fps. But they weren't. Clearly there is a lot more to it than that.

yeah that logic is not quite correct...

CRT and plasma's work by flashing a scene at a certain (fixed) speed...

LCD's only change pixels (color) when there is a need....  and it takes a different amount of time to change from one picture to the next depending on the difference in color the pixels have to present (hence it takes time for the crystals to be aligned) .... changing from white to black is obviously the hardest and takes the longest... (LCD crystal relaxed means max light permitted through the sub pixel and LCD crystals with full current means fully closed and max black (each pixel has 3 sub pixels with colored filters)...  But a change between 2 similar colors is realitively easy for an LCD...

There is a theory going round that would improve the movement in LCD's which goes as follows...

The motion blurring effect present in some LCD's is due to the fact that there is a transistion phase (time) for a pixel to change color.  This transistion time means that there is a progression from the picture/frame you currently see and picture/frame that comes next.  During this transition you are in no mans land, and there is light and different colors that are not appart of the picture being displayed.. (Note not everyone can detect this transistion phase at it happens very fast)

To combat this, they feel that a strobing backlight would be ideal.  In effect displaying a picture, turn off the back light for a fraction of a second, and then display the next picture, then turn the back light on again.  This would stop the viewer from seeing the transistion phase, which is supposedly the reason for percieved blur.

Now some of us are not as sensitive to the percieved motion blur as others and for those lucky people it probably wouldnt make a big difference.

Ajax9000, on May 15 2006, 05:37 PM, said:

Depending on their eyes, source material (e.g. image moving or not, high/low contrast, colour), ambient conditions, etc. most people will stop noticing any refresh artifacts somewhere between 50 and 90Hz.

e.g.

Google "Critical flicker frequency".

Adrian

again that is based on a display that displays on picture, then totally refreshes the screen with another image (frequency = how often the picture is refreshed a second) .. i.e plasma or crt.  LCD's do not work in this way...


But i agree... if you can't notice any blurring on an LCD what does it matter what refresh rate it claimed to be... its all personal opinion..

I actually havent seen this DX5. I have only seen the older versions that apparently had 10ms response times and i didnt think much of them... but i would be happy if this new LCD is as good as the poster says....  

I would still like to see the 6ms b-t-w in writting somewhere..... i havent found it mentioned anywhere ... in fact i have seen no mention of response time at all... you would have thought it would be a major selling tool..  

I have emailed JVC to get to the bottom of it..

____

Hi and thank you for e-mailing JVC Australia.

The response time on the LT-Z37DX5 from b t w is 6 ms.

Regards,


JVC Australia
1300 728 225
____

apparently it is 6ms b-t-w .. strange that they are not advertising this fact...

[mejimbo]

fobfob, on May 15 2006, 05:40 PM, said:

. . . IMO image processing techniques account for much of the PQ that people see. The signal must be decoded, interlaced, scaled, and other optional techniques such as colour and noise filters applied, before finally being displayed. . . . .

I agree.
What this does mean based on the observations by optusman is that JVC probably spent more money on the electronics. A panning camera at a sporting event is a nice test for a scaling engine - if the ball does not blur and if the background does not blur during a crowd pan (as per a CRT and plasma) then pretty good. I am not saying LCD is inferior to Plasma - just that is it newer and "probably" costs more for the LCD panel at this early stage of the product lifecycle and so there is less to spend on the scaling electronics to get to the right price point. Off my technology hobby hourse now. But in the end the eyes have it. Buy what you like - just test it first - DVD playback and playback of sporting events are my choices . .

[Drizt]

mejimbo, on May 15 2006, 06:40 PM, said:

Buy what you like - just test it first - DVD playback and playback of sporting events are my choices . .

agreed..

the bravia is well and truely brilliant with motion and sporting events... no complaints here... if the JVC is even better with regards to motion then 2 thumbs up.... I wonder if i would even notice the difference in motion between the two.. as the bravia is good enough for me...

[optusman]

Drizt, on May 15 2006, 04:38 PM, said:

What price were they doing it for ?

About $3500 (rrp $4700) but I didn't really push it.  If so, would expect $3K would be possible.  Don't think that HN store had sold any.  Model was on display for a couple of months but he wasn't really sure.

Would love for you to look at it and give your summary.  As I said, image not as sharp as the Bravia V, would hope the digital noise/interference would disappear if you took it home.

Some days, I sit back and look at my 10 year old Sony CRT with Foxtel SD and the picture looks better than most I've seen in store of any technology (for sport that is).

Anyone else know if/when other 6ms panels are due ?

[Drizt]

Sharp has a 6ms coming out... well a few.. in america there is the D90 1080p models (friggin awesome specs, 2 HDMI, i DVI-I all accepting 1080p signals   )  and the D40 and D50 panels which are the lesser siblings...

and there is the Philips 1080p (accepts 1080i) 37pf9830/10 with 6ms.... (awesome when given HD but absolutely **** with SD)

The older JVC's did nothing for me, too much noise, and bad viewing angles....   hope this model is better on both accounts..

viewing angles on all LCD's before the samsung/sony panels were the only thing putting me off lcds..

optusman, on May 15 2006, 07:00 PM, said:

About $3500 (rrp $4700) but I didn't really push it.  If so, would expect $3K would be possible.  Don't think that HN store had sold any.  Model was on display for a couple of months but he wasn't really sure.

Would love for you to look at it and give your summary.  As I said, image not as sharp as the Bravia V, would hope the digital noise/interference would disappear if you took it home.

Some days, I sit back and look at my 10 year old Sony CRT with Foxtel SD and the picture looks better than most I've seen in store of any technology (for sport that is).

Anyone else know if/when other 6ms panels are due ?

[optusman]

Drizt, on May 15 2006, 07:00 PM, said:

agreed..

the bravia is well and truely brilliant with motion and sporting events... no complaints here... if the JVC is even better with regards to motion then 2 thumbs up.... I wonder if i would even notice the difference in motion between the two.. as the bravia is good enough for me...

You definitely would notice the difference when the camera pans and follows the flight of the ball (both TV's were set up back to back) As they say beauty is in the eye of the beholder

Drizt, on May 15 2006, 07:24 PM, said:

Sharp has a 6ms coming out... well a few.. in america there is the D90 1080p models (friggin awesome specs, 2 HDMI, i DVI-I all accepting 1080p signals   )  and the D40 and D50 panels which are the lesser siblings...

and there is the Philips 1080p (accepts 1080i) 37pf9830/10 with 6ms.... (awesome when given HD but absolutely **** with SD)

The older JVC's did nothing for me, too much noise, and bad viewing angles....   hope this model is better on both accounts..

viewing angles on all LCD's before the samsung/sony panels were the only thing putting me off lcds..

any idea if / when it will hit oz?

[fobfob]

Drizt, on May 15 2006, 05:55 PM, said:

.... changing from white to black is obviously the hardest and takes the longest...

No, not obviously. In fact this is wrong. The speed with which the LCD subpixel changes from the old "brightness" to the new is determined by the voltage applied to it. A black to white (or vice versa) transition presents the highest voltage step to the pixel and hence is a faster transition than a "grey to grey" transition. As stated before, this is the reason Sony (for example) quote "grey to grey". They are being honest and providing the worse case. "BTW" specs should be treated with caution.

This thread shows that we will be chasing this particular spec for a long time. Clearly the marketing still works. I'm gonna trump you all with my new 2ms panel soon (already available as PC monitors). Then all your 6ms panels are gonna be worthless!  :ph34r:
500 fps here we come!

[optusman]

fobfob, on May 15 2006, 08:13 PM, said:

No, not obviously. In fact this is wrong. The speed with which the LCD subpixel changes from the old "brightness" to the new is determined by the voltage applied to it. A black to white (or vice versa) transition presents the highest voltage step to the pixel and hence is a faster transition than a "grey to grey" transition. As stated before, this is the reason Sony (for example) quote "grey to grey". They are being honest and providing the worse case. "BTW" specs should be treated with caution.

This thread shows that we will be chasing this particular spec for a long time. Clearly the marketing still works. I'm gonna trump you all with my new 2ms panel soon (already available as PC monitors). Then all your 6ms panels are gonna be worthless!  :ph34r:
500 fps here we come!

Wouldn't black-to-black be the worst case scenario to quote?

[Drizt]

optusman, on May 15 2006, 08:24 PM, said:

Wouldn't black-to-black be the worst case scenario to quote?

yeap....

heres an article.... -> obviously dude above has read something similar to this....
http://www.pcworld.c...d,121906,00.asp

and heres another one
http://reviews.cnet...._7-6358806.html



so in effect, the JVC is 12ms (roughly) for black-t-black or 6ms black-t-white, who knows what it is g-t-g

g-t-g is subjective at best, what shade of grey do they measure to ? (see the second link)


God damn, i just wish they all used b-t-b or did individual b-t-w  and w-t-b..  as thats an easily defined standard

g-t-g is a marketing ploy.  (see the second link)


here is another reason why g-t-g is difficult to gauge

__snip from here -> http://www.detnews.c.../603130303/1013
For instance, ViewSonic says that its VX724 monitor has response times of 3 milliseconds for gray-to-gray and 6 milliseconds for black-to-white, while its VX922 is 2 milliseconds for both gray-to-gray and black-to-white.
__

from reading this link you wouldnt know which method of measurement to use as a true comparison..



SO if the bravia is g-t-g 8ms, what is it b-t-w and then b-t-b ???

[fobfob]

optusman, on May 15 2006, 08:24 PM, said:

Wouldn't black-to-black be the worst case scenario to quote?

Well black to black would be 0ms because you're already there It is the difference in luminosity that matters. Instead of me spurting half truths let's look at what a reasonably reputable source has to say.

http://www.tomshardw...5/17/page6.html

Drizt, on May 15 2006, 08:44 PM, said:

from reading this link you wouldnt know which method of measurement to use as a true comparison..
SO if the bravia is g-t-g 8ms, what is it b-t-w and then b-t-b ???

regardless, the whole thing is academic. There is nothing wrong with the logic that says if the response time of your panel is lower than the maximum required update rate, which in this case is 50Hz fields, anything else is marketing.

Sorry dudes but it's as simple as either the manufacturers are full of crap or response time is a red herring. Choose your pick. If the former, then why even look at the specs? If the latter, when why even look at the specs? hmm see a pattern?

[Drizt]

Mate you havent read what i said many posts ago...  I wish i still had that link i had that described what caused the blurring phenomenon....  i posted it ages ago... maybe ill search for it later.

The reason LCD's are not measured in frequency is because the picture is not updated at a set interval...  (i.e. its not an image that is updated at a set frequency)

a 10ms LCD is not the same as a 100hz CRT TV...

a 100Hz CRT will FLASH/SCAN whatever you wish to call it an image 1 every 1/100 of a second with an interval of nothingness between images (of course a CRT doesnt lose the image straight away it persists for a period of time...)

a 10ms (best case - not worst or average case) LCD describes the time it takes for a LCD to change states...... it doesnt just flash one image in its entirety then go blank then flash the image again like a CRT...  It has one image, then has to 'transmute' into the next image.... no blanks....  its the transmuting stage that causes what people see as blurring.

if it was as simple as converting 10ms into 100Hz then they would advertise it that way....


I never thought i would say this, but i need owen in here to help me explain this..

fobfob, on May 15 2006, 08:57 PM, said:

Well black to black would be 0ms because you're already there It is the difference in luminosity that matters. Instead of me spurting half truths let's look at what a reasonably reputable source has to say.

http://www.tomshardw...5/17/page6.html
regardless, the whole thing is academic. There is nothing wrong with the logic that says if the response time of your panel is lower than the maximum required update rate, which in this case is 50Hz fields, anything else is marketing.

Sorry dudes but it's as simple as either the manufacturers are full of crap or response time is a red herring. Choose your pick. If the former, then why even look at the specs? If the latter, when why even look at the specs? hmm see a pattern?

[Billy Two Hats]

Then you could have been a little less discourteous to him in some of your earlier posts!

[fobfob]

Drizt, on May 15 2006, 09:09 PM, said:

a 100Hz CRT will FLASH/SCAN whatever you wish to call it an image 1 every 1/100 of a second with an interval of nothingness between images (of course a CRT doesnt lose the image straight away it persists for a period of time...)

Well I've never heard CRT flicker being described as a good thing! Usually people think of it as a bad thing, or at least those who know that it exists.

One possible weakness in your argument is that a 50Hz CRT, as we know displays motion very well. Then a 100Hz CRT should be worse because the supposed dead time between scans is halved. But faster CRTs display motion as well as slower CRTs.

I can see your point however, and if true would certainly point toward strobing backlight as a possible solution. Or should we just go back to CRTs?

I should also say that if your argument is true, it is not necessarily clear that a faster LCD response time will eliminate the problem.

I still contend that either response time specs are rubbish or it's all a red herring. In either case there's little point in looking at that particular spec.

[Billy Two Hats]

fobfob, on May 15 2006, 08:57 PM, said:

Well black to black would be 0ms because you're already there
~~

Black to white to black?

[optusman]

Billy Two Hats, on May 15 2006, 09:25 PM, said:

Black to white to black?

You know that's what I meant.  
Seems to me there is no black or white answer, just shades of grey in between ...ha ha
(well someone had to say it!!)

[Drizt]

optusman, on May 15 2006, 09:32 PM, said:

You know that's what I meant.  
Seems to me there is no black or white answer, just shades of grey in between ...ha ha
(well someone had to say it!!)

very true.... dont get me wrong response time is obviously important... just hard to work out how to compare other TV's as they dont all use the same measurements..

[Suzuki]

On another note, is the in-built tuner a HD, SD or Anoluge