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Old 04-09-2007, 14:38
philnavigator
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I thought I had this sorted in my head until I read a reply in the Video Forum of What Video mag recently, where they stated that a Sony LCD with 1920 x 1080 res, showed a 1080p signal in 1080i form.

I am sure that I have read previously that LCD and Plasma are inherently progressive and therefore show any signal in 'p' rather than 'i' form. So how can a 1920 x 1080 LCD screen not be showing a 1080p picture from such a signal?
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Old 04-09-2007, 15:02
Nigel Goodwin
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Presumably the set doesn't accept 1080P signals?, so the scaler may convert them to 1080i?.

The i and P thing doesn't really apply to LCD or Plasma because they aren't scanned images like a CRT - the image is written into memory then displayed as a full image, rather than building up line by line like on a CRT.
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Old 04-09-2007, 15:10
philnavigator
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The set in question was a Sony 42W2000 LCD, and was described as 1920 x 1080 res, able to accept 1080p signals, but was not full HD. The reply in the mag stated that the set would then show a 1080p signal as a 1080i picture???
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Old 04-09-2007, 15:59
Jarrak
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A LCD display is a Progressive display so I'm not quite sure where the article/review was going.

It would make some sense if the panel only accepted 1080i and then de-interlaced it for display at 1080p but not the other way around.
Of course the real critical function is the ability to accept 1080p at 24hz thus making full use of HD DVD and Blu-ray sources, perhaps that is where it is lacking and hence the use of not "full HD".

You almost long for the day when it just had to be "HD Ready"



Is the 42W2000 a new model, little online presence and nothing on the SONY UK website.
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Old 04-09-2007, 17:12
Nigel Goodwin
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A LCD display is a Progressive display so I'm not quite sure where the article/review was going.
Reviews rarely make much sense!


It would make some sense if the panel only accepted 1080i and then de-interlaced it for display at 1080p but not the other way around.
Of course the real critical function is the ability to accept 1080p at 24hz thus making full use of HD DVD and Blu-ray sources, perhaps that is where it is lacking and hence the use of not "full HD".
Full HD only needs to be a 1080 panel, I don't really see as this 24Hz lark is anything to do with being 'full HD' or not?.


You almost long for the day when it just had to be "HD Ready"



Is the 42W2000 a new model, little online presence and nothing on the SONY UK website.
No, it's an old model, don't forget to add KDL to the front of the model number, it's probably the oldest current Sony LCD there is?. Good sets though, and a great picture, which is probably why it's been going for so long? - but I suspect it's got to be replaced fairly soon, if nothing else for a model with more HDMI's.
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Old 04-09-2007, 17:20
Jarrak
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Full HD only needs to be a 1080 panel, I don't really see as this 24Hz lark is anything to do with being 'full HD' or not?.


Probably not, I was just trying to understand why a review would not class a 1920*1080 panel that accepts 1080p via HDMI as being not Full HD or whatever todays marketing term is.
The lack or existence of 1080p/24 support is the only thing I could think of for a reviewer not to class it as the ultimate spec wise and it is something a pre-recorded HD owner would want to take advantage of the HD media's native framerate.



No, it's an old model, don't forget to add KDL to the front of the model number, it's probably the oldest current Sony LCD there is?. Good sets though, and a great picture, which is probably why it's been going for so long? - but I suspect it's got to be replaced fairly soon, if nothing else for a model with more HDMI's.

That would explain the lack of info on the SONY UK website, why promote older cheaper models when the latest profitable panels are ready to be sold
Even googling KDL 42W2000 only turns up foreign language sites, surely they don't dump old tech onto unsuspecting markets do they
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Old 04-09-2007, 17:27
Nigel Goodwin
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Probably not, I was just trying to understand why a review would not class a 1920*1080 panel that accepts 1080p via HDMI as being not Full HD or whatever todays marketing term is.
The lack or existence of 1080p/24 support is the only thing I could think of for a reviewer not to class it as the ultimate spec wise and it is something a pre-recorded HD owner would want to take advantage of the HD media's native framerate.
Like I say, never trust a review! - they generally say what they are paid to say!.


That would explain the lack of info on the SONY UK website, why promote older cheaper models when the latest profitable panels are ready to be sold
It's still a current model, and still an expensive one! - it's not a cheaper set at all.

It's also still listed on the Sony UK website, here's a quick quote from it:

40” Full HD W2000 Sony Bravia LCD TV has 1920x1080 resolution, Live Colour Creation for incredible colour reproduction and BRAVIA ENGINE for high performance picture quality
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Old 04-09-2007, 22:10
carefree cook
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the w2000 IS full HD this review is ball sh!t. the 1920X1080p is a full HD signal. ffs on the bottom right of all w2oo sets there is a sony gold sticker saying 'Full 1080p HD'


Presumably the set doesn't accept 1080P signals?, so the scaler may convert them to 1080i?.

The i and P thing doesn't really apply to LCD or Plasma because they aren't scanned images like a CRT - the image is written into memory then displayed as a full image, rather than building up line by line like on a CRT.

i and p do apply to lcd and plasma, although the images arnt scanned, they are to do with the refresh rate of the pic, the i (interlaced) denotes every other line being refreshed every other second, P (progressive) every line reffreshed every second, hence a more fluent picture compared to I
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Old 04-09-2007, 22:47
philnavigator
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i and p do apply to lcd and plasma, although the images arnt scanned, they are to do with the refresh rate of the pic, the i (interlaced) denotes every other line being refreshed every other second, P (progressive) every line reffreshed every second, hence a more fluent picture compared to I[/quote]

This could be what they were referring to in the mag. Let me clarify that this was not a review of the set, it was a query from someone who owned this set, in the Video Forum letters pages, and in the reply they said that it was 1920 x 1080 res but although it would accept a 1080p signal, it would only display it at 1080i, thereby making it not quite Full HD, apparently as per the Sony website at the time.

So what you are saying is that LCD/Plasma tv's can show an i picture by alternating the fields in a frame, rather than converting all inputs to p?
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Old 04-09-2007, 23:20
Jarrak
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It's also still listed on the Sony UK website, here's a quick quote from it:



Well that would explain it, the copy and paste I took from the OP's post was for the "Sony 42W2000" and that is what the results from google were for.
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Old 05-09-2007, 00:46
bobcar
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i and p do apply to lcd and plasma, although the images arnt scanned, they are to do with the refresh rate of the pic, the i (interlaced) denotes every other line being refreshed every other second, P (progressive) every line reffreshed every second, hence a more fluent picture compared to I
If the picture was refreshed very second or every other second the picture would be somewhat jerky.

Incidentally LCDs and plasmas do not display interlaced pictures, they accept the input but always de-interlace them before displaying.

Interlacing should have been consigned to the scrapheap with the introduction of HD, it was useful for old CRT televisions (and cameras) but is not needed now even with CRTs.
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Old 05-09-2007, 19:59
carefree cook
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If the picture was refreshed very second or every other second the picture would be somewhat jerky.
sh!t, i might need a mili in there somewhere
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Old 05-09-2007, 20:17
tellytart1
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Yep 1 frame =1/25 second = 40 miliseconds
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Old 06-09-2007, 18:56
philnavigator
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Well the only conclusion I can reach, if these tv's always de-interlace, is that the answer in the mag was wrong! If the telly can show 1080 lines, and only does p, then its full HD right?

I have just sent an email querying the point, to the same mag letters page, so I will watch future issues closely....

Incidentally, as someone who still has a 36in CRT (that does p) I was wondering if these tellys always show any input on 1080p, or do you have to manually select it? With all the different sources around, and the increasing number of upscaling equipment, it occurred to me that if you have a telly that always upscales, and does it well, then it doesn't really matter what signal you give it! I mean would my DVD picture be best on a 1080p telly, if it was sent at 720p from my Pansonic DVD Rec via HDMI, or at 576p through component from my Pioneer player?
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Old 06-09-2007, 22:00
Nigel Goodwin
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Incidentally, as someone who still has a 36in CRT (that does p) I was wondering if these tellys always show any input on 1080p, or do you have to manually select it?
What 36 inch CRT set does progressive, or 1080?.


With all the different sources around, and the increasing number of upscaling equipment, it occurred to me that if you have a telly that always upscales, and does it well, then it doesn't really matter what signal you give it! I mean would my DVD picture be best on a 1080p telly, if it was sent at 720p from my Pansonic DVD Rec via HDMI, or at 576p through component from my Pioneer player?
As always, try it and see - it's mainly down to which has the best upscaler - which is why the Sky HD box allows you to set it's output to 1080i, 720P, or Auto (sends it out as received).
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Old 06-09-2007, 23:04
Jarrak
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What 36 inch CRT set does progressive, or 1080?.




There were a number of CRT's that had a component input for connecting to a DVD player, not sure exactly how they worked as in converting Progressive to Interlaced or simply being more in tune with PC monitors which can display a progressive CRT signal.

They were around long before HD was launched so my guess is that they have no capacity for accepting 720p or 1080i (wasn't on the drawing board) just as the first HD CRT's could only accept 1080i.
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Old 07-09-2007, 01:37
bobcar
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I mean would my DVD picture be best on a 1080p telly, if it was sent at 720p from my Pansonic DVD Rec via HDMI, or at 576p through component from my Pioneer player?
Don't forget 576p via HDMI as that's likely to give the best result with a decent TV, though as Nigel said it's always best to try different settings.
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Old 09-09-2007, 21:58
philnavigator
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What 36 inch CRT set does progressive, or 1080?.

Sorry, I may have misled you with my last post. I meant that still being a CRT owner, I was wondering about the telly's already discussed on this thread, ie flatscreen full HD.

As it happens, my CRT is a three year old Toshiba 36ZP48, which gives (IMO) stunning pictures from my Pioneer DV585 in 576p via component, but it has no HDMI.

So when it comes to upgrade time, which I am no hurry with, its all down to experimentation and personal taste?
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Old 13-09-2007, 10:06
iain
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on a similar note, i was looking at the new(ish) sony kdl 32 D 3000.

if you look on the website, it lists 1080i, even tho' it isn't full HD.

i guess for full HD it's all in the set's resolution, ie 1920x1080 rather than 1366x768.

but it accepts 1080i inputs, and presumably puts them out as 1080p?

is this something that other HD ready (as opposed to Full HD) sets won't do?

Iain
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Old 13-09-2007, 10:10
Nigel Goodwin
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on a similar note, i was looking at the new(ish) sony kdl 32 D 3000.

if you look on the website, it lists 1080i, even tho' it isn't full HD.

i guess for full HD it's all in the set's resolution, ie 1920x1080 rather than 1366x768.
Yes it is.


but it accepts 1080i inputs, and presumably puts them out as 1080p?
Not really, it displays the picture in a Progressive manner (it can't do anything else), but that doesn't make it a 1080P picture. Don't worry about it, it's a great set with a great picture! - 1080P makes sod all difference!.


is this something that other HD ready (as opposed to Full HD) sets won't do?
No, any HD Ready set does this, it's what the HD Ready logo is all about really.
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Old 13-09-2007, 10:36
iain
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Yes it is.

Not really, it displays the picture in a Progressive manner (it can't do anything else), but that doesn't make it a 1080P picture. Don't worry about it, it's a great set with a great picture! - 1080P makes sod all difference!.

No, any HD Ready set does this, it's what the HD Ready logo is all about really.
thanks Nigel - just been reading a few threads and getting my head round it.

just got a bit confused looking at the sony site - you look at screen inputs, and it lists 1080i, and i thought i'd read something about this being a feature.

was looking at one in john lewis, but the picture (SD) really didn't look good at all - sort of grainy, almost like it was poor reception. how much of this is down to being badly set up?

also saw one in the sony centre with a sky HD feed, and the picture was superb - had some on screen titles which were brilliantly clear and sharp.

considering i'd figured on having to spend £1000-£1500 for a great, spend as much as you can afford, set, something like this one for around £750-£900 would be spot on.

Iain
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Old 13-09-2007, 11:06
Nigel Goodwin
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thanks Nigel - just been reading a few threads and getting my head round it.

just got a bit confused looking at the sony site - you look at screen inputs, and it lists 1080i, and i thought i'd read something about this being a feature.

was looking at one in john lewis, but the picture (SD) really didn't look good at all - sort of grainy, almost like it was poor reception. how much of this is down to being badly set up?
It might well have been poor reception?, often aerial systems in shops are pretty poor. Bear in mind you probably viewed from too close as well, so it looks worse than it really is.


also saw one in the sony centre with a sky HD feed, and the picture was superb - had some on screen titles which were brilliantly clear and sharp.
That's what HD is all about!


considering i'd figured on having to spend £1000-£1500 for a great, spend as much as you can afford, set, something like this one for around £750-£900 would be spot on.
Prices keep falling, and (often) quality keeps going up.
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Old 13-09-2007, 17:20
carefree cook
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It might well have been poor reception?, often aerial systems in shops are pretty poor. Bear in mind you probably viewed from too close as well, so it looks worse than it really is.

most likely was. shops dont/cant have all sets connected with a direct aerial. most have many splitters, and no matter how good the amp for the siganl is the end picture is mostly poor and grained. plus viewing distance. nightmare in our shhop!!
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Old 14-09-2007, 00:08
pawlo
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the KDL-40W200 will only accept and dissplay a 1080p signal over HDMI. NOT the component or VGA input, it will scale down in this case.
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Old 14-09-2007, 09:44
Nigel Goodwin
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the KDL-40W200 will only accept and dissplay a 1080p signal over HDMI. NOT the component or VGA input, it will scale down in this case.
The 40W2000 is a full HD panel, so there's nothing to scale down to?.
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