Nobody will listen to a word you say on this thread now after that clanger, I'd bet. What rubbish...
Exactly, some people need to get their eyes tested or invest in the right AV gear. When these HD threads spring up I always end up shaking my head in dismay.
I can't really see a difference between SD and HD tv.
I have a Bush HD Freesat receiver and when I switch from a prog that is on say BBC2 and BBC HD at the same time they look the same to me.
It depends on how you've got them connected up. A simple scart lead will do zilch for the High Definition signal. You need a proper High Definition lead to experience it.
It's more than three times. You're only thinking in one dimension. It's over six times.
SD = 307,200 pixels.
HD = 2,073,600 pixels.
I've been told this before but I still don't get it. If there's 640 lines across, then, 480 lines up, how can this amount to what you've got there? Are they actually saying that it's 640 times 480 lines, or just 640 by 480 like you would measure a carpet for instance?
I've been told this before but I still don't get it. If there's 640 lines across, then, 480 lines up, how can this amount to what you've got there? Are they actually saying that it's 640 times 480 lines, or just 640 by 480 like you would measure a carpet for instance?
Like how you would measure the square of a carpet. 640x480= 307,200 pixels in that square area. In HD they have crammed more pixels into that size allowing for more detail.
Imagine a tin of baked beans - more juice = SD, more beans = HD
Like how you would measure the square of a carpet. 640x480= 307,200 pixels in that square area. In HD they have crammed more pixels into that size allowing for more detail.
Imagine a tin of baked beans - more juice = SD, more beans = HD
No, that's not exactly what I meant. I wasn't talking about pixels, but LINES of pixels. 640 lines across by 480 lines upwards.
It depends on how you've got them connected up. A simple scart lead will do zilch for the High Definition signal. You need a proper High Definition lead to experience it.
I have an HDMI between the HD Freesat receiver and the HD tv.
I've been told this before but I still don't get it. If there's 640 lines across, then, 480 lines up, how can this amount to what you've got there? Are they actually saying that it's 640 times 480 lines, or just 640 by 480 like you would measure a carpet for instance?
Don't know where you got 640x480 from, that's a computer resolution not a TV resolution. US TV uses 720x480 (345600 pixels) and European TV uses 720x576 (414720 pixels). HD is 1920x1080 (2073600 pixels) so its 5 times better in Europe and 6 times better in the US.
The article you quoted is for a very specific case, going from 24p to 1080i25 or 1080p25, where you are going from 24 fields a second to 25 frames a second, be them 25 progressive fields or 50 interlaced fields, with the fields making up each interlaced frame only containg the info of 1/25s, so in essence the same thing, when you add tv deinterlacing (lets forget any effects of the change in frame rate .
In the real world, motion is continuous. The main difference is 1080i25 is a field rate of 1/50 and 1080p is 1/25fps. So for fast motion, or a live scene it is not a fair comparison and there will be a difference, you should really compare 1080i25 and 1080p50 so you have the same field rate per second, in which case there is a big difference . If you have a frame with no motion at all, then there is no difference between 1080i25 and 1080p25 ( assuming the TV applies some good deinterlacing).
The problme with 1080i25 is a lot of TVs are still not that great at deinterlacing.
Depending on the scene, and level of motion, there can be a lot of difference between 1080i and 1080p.
Don't know where you got 640x480 from, that's a computer resolution not a TV resolution. US TV uses 720x480 (345600 pixels) and European TV uses 720x576 (414720 pixels). HD is 1920x1080 (2073600 pixels) so its 5 times better in Europe and 6 times better in the US.
I got told about the 640 lines thing from someone ages ago. I've just found out now that it, is in-fact, 720x576. High Definition can also be 1280x720 as well.
The article you quoted is for a very specific case, going from 24p to 1080i25 or 1080p25, where you are going from 24 fields a second to 25 frames a second, be them 25 progressive fields or 50 interlaced fields, with the fields making up each interlaced frame only containg the info of 1/25s, so in essence the same thing, when you add tv deinterlacing (lets forget any effects of the change in frame rate .
In the real world, motion is continuous. The main difference is 1080i25 is a field rate of 1/50 and 1080p is 1/25fps. So for fast motion, or a live scene it is not a fair comparison and there will be a difference, you should really compare 1080i25 and 1080p50 so you have the same field rate per second, in which case there is a big difference . If you have a frame with no motion at all, then there is no difference between 1080i25 and 1080p25 ( assuming the TV applies some good deinterlacing).
The problme with 1080i25 is a lot of TVs are still not that great at deinterlacing.
Depending on the scene, and level of motion, there can be a lot of difference between 1080i and 1080p.
Well said.
In the case of movies and high end dramas and nature documentaries they use something called segmented frame where the frame rate is half the field rate and therefore both fields come from the same frame so its effectively a way of smuggling 25p onto a 50i standard. In the case of most other material and especially fast moving sport, the broadcaster simply throws away half the lines in the picture and leaves your telly to try and guess what information they contained and make something up, a lossy process which most TVs are quite bad at anyway.
It is not possible (with human eyes) to differenciate between SD and HD on a 19" screen.
The resolving power of the eye is expressed as angular resolution, so you can see as much detail on a 21 inch screen at 3 feet as you can on a 42 inch screen at 6 feet. Personally I see a huge difference between DVDs and blu-ray on my 15 inch laptop screen.
I have an HDMI between the HD Freesat receiver and the HD tv.
Well then your TV settings are crap, or your TV is crap. It's a horrid set top box too, but not for picture purposes, they are pretty much identical in that respect. What TV, and have you ever changed he settings from unpacking it? 1st thing, get the sharpness turned down. Most TVs look best with the sharpness turned to minimum, but if it gets all fuzzy, yours is an exception. All other settings at halfway and you may be close. You can get DVDs to help you get your settings right, or if you have a DVD with a THX badge on the case, it has a little easter egg in the languages section, the THX optimiser. Try it, you may be surprised.
What do you mean by an HD print?, film is much higer resolution than HD
I think he's saying they haven't done an HD transfer, presumably people think this because the films are not available on blu-ray yet, but they are shown on HD movie channels so I'm guessing they must have been scanned in HD. That's not to say that the version ITV have is necessarily HD of course.
I think he's saying they haven't done an HD transfer, presumably people think this because the films are not available on blu-ray yet, but they are shown on HD movie channels so I'm guessing they must have been scanned in HD. That's not to say that the version ITV have is necessarily HD of course.
It may be HD, but not the bandwidth we'd get on a Blu Ray disc. And of course broadcast sound is usually fairly rubbish, whereas a blu ray should be 6 channels of CD quality, or it will be if it's from Lucasarts.
No you can't !! You are being taken in by the hype. It is not possible (with human eyes) to differenciate between SD and HD on a 19" screen.
Nobody will listen to a word you say on this thread now after that clanger, I'd bet. What rubbish...
However... and in the real World this is very important because many people don't realise it... from a typical seating position in an average family living room (3m - 4m eye-screen distance) you will not be able to distinguish the higher resolution of HD TV from SD TV with a 19 inch set. Human eyes are not good enough. You probably need a set twice that size or more and to see the full detail of 1080, a screen size well over 50 inches (from 3 - 4m).
Don't know where you got 640x480 from, that's a computer resolution not a TV resolution. US TV uses 720x480 (345600 pixels) and European TV uses 720x576 (414720 pixels). HD is 1920x1080 (2073600 pixels) so its 5 times better in Europe and 6 times better in the US.
Real-World resolution is a linear measure i.e. it is measured in one direction. This is how opticians, astronomers and microscopers do it and there is no valid reason why TV vendors should do it any differently. They use areal resolution only to make something that's twice the resolution seem like it's 4 times. Well it isn't. It may contain 4 times the amount of information but that is not equivalent to 4 x the (linear) resolution.
There is a very good reason why linear is the best way to compare resolution (unless you want to trick people). You can double an object size (3 ft tall becomes 6 ft tall) then move twice as far away... and you will see the same amount of detail in it. The visible resolution is the same. Conversely, if you then move to half the distance, you will see it at twice the visible resolution, not 4 times. For example, on an optician's chart... or words on your computer screen. Twice the width and height is twice the resoution, not 4x (except for digital camera and flat panel TV vendors).
Couple that with the fact that on BBC HD (among some but not all broadcasters) the broadcast HD resolution is 1440 x 1080 and you can see that the improvement in maximum resolution, i.e. with a "full HD" screen, is approximately 1440/720 =2.0 horizontally; and about 1080/576 = 1.875 vertically. On some (perhaps all?) Sky HD channels it will be a bit more, if they broadcast at 1920 x 1080.
Couple all the above with the fact that most viewers watch TV from 3m - 4m distance, their screens are typically "HD ready" and 42 inches or less and it's not hard to see why the "wow" factor simply isn't there for many people.
Yes HD is much better... you can identify an object of about half the size on BBC HD compared to BBC SD (if you are close enough and the screen's a full HD). In my book that makes BBC HD (just less than) twice as good in resolving power as SD... but claims that it's "5 x better" are no more than hype. The answer to the question in the thread title is: yes... but with the right equipment, setup and viewing distance for screen size, HD is still much better than the original poster seems to think.
Hi folks, was in looking at tv's the other day and what struck me most was this whole HD picture promotion thats going on at the moment! there i was watching a split screen being promoted on all tv's showing 1 half HD and the other not! Now my eyesight aint that bad but the half that wasnt HD was like a tv with the settings for sharpness and contrast turned down to the lowest you can get! The pic i have on my tv was more like the hd pic although it aint hd!
anyone else feel the whole HD picture fad is a bit misleading!
You do realise that on most TVs the sharpness is supposed to be turned down as low as you can get, except on TVs where it goes below zero and actually starts softening the picture. Adding sharpness is just adding false detail to the picture that isn't supposed to be there, and it looks awful. Most people have their contrast turned up way too high as well so that detail is lost in the very bright and very dark parts of the picture. It may just be that the demo was set up correctly but that's not what most people are used to seeing. Standard definition does look particularly crap blown up on a large screen.
Rather than take some demo's word for it, try watching the same movie on DVD and blu-ray and see if you notice the difference, or try switching between the SD and HD versions of a programme being simulcast on BBC HD or ITV HD, be careful with C4HD though as some material is upscaled on there.
Twice the width and height is twice the resoution, not 4x (except for digital camera and flat panel TV vendors).
I got sucked in there comparing pixel count, but you're right of course - optical resolution is measured in line pairs, so line count is a more meaningful measure of display resolution than pixel count.
It's the shops selling them. I wa sin John Lewis the other day (I don't shop there, I just browse ) and the amount of HD TVs they clearly had set up incorrectly was quite frustrating.
They were using SCART sockets in some of them, which is pointless if the selling point of the TV is it's in high definition!
HD is briiliant but it is being ruined by the channels constantly putting down their bit rates,BBC HD used to be great, but now there is not a lot of difference.
Thanks - I wasn't aware of that.
The Ad Standards lot ought to get hold of this in much the same way they've taken on broadband companies who say one thing and deliver far less. There should be a minimum bit rate below which it cannot be classified as HD.
"You are being taken in by the hype. It is not possible (with human eyes) to differenciate between SD and HD on a 19" screen."
Maybe not resolution-wise, Sid (although I would argue with that anyway), but there's a significant reduction in those horrible wiggly artefacts that SD digital suffers from. In fact they don't appear at all on HD, and this give a much cleaner looking picture even when you watch an HD broadcast at SD resolution.
"You are being taken in by the hype. It is not possible (with human eyes) to differenciate between SD and HD on a 19" screen."
Maybe not resolution-wise, Sid (although I would argue with that anyway), but there's a significant reduction in those horrible wiggly artefacts that SD digital suffers from. In fact they don't appear at all on HD, and this give a much cleaner looking picture even when you watch an HD broadcast at SD resolution.
yes indeed. It's perfectly possible to spot an HD broadcast even if it's via RF feed in the next room, if you know what you are looking for.
"You are being taken in by the hype. It is not possible (with human eyes) to differenciate between SD and HD on a 19" screen."
Maybe not resolution-wise, Sid (although I would argue with that anyway), but there's a significant reduction in those horrible wiggly artefacts that SD digital suffers from. In fact they don't appear at all on HD, and this give a much cleaner looking picture even when you watch an HD broadcast at SD resolution.
Ah, but are you talking about a Standard Definition signal being broadcast through a High Definition television though? The Standard Definition image will have to be stretched in order to fit the higher resolution.
Comments
Exactly, some people need to get their eyes tested or invest in the right AV gear. When these HD threads spring up I always end up shaking my head in dismay.
It depends on how you've got them connected up. A simple scart lead will do zilch for the High Definition signal. You need a proper High Definition lead to experience it.
I've been told this before but I still don't get it. If there's 640 lines across, then, 480 lines up, how can this amount to what you've got there? Are they actually saying that it's 640 times 480 lines, or just 640 by 480 like you would measure a carpet for instance?
Not exactly true. You do realise that not ALL LCD televisions are high in resolution, don't you? They have 640x480 LCD televisions for sale in Argos.
Like how you would measure the square of a carpet. 640x480= 307,200 pixels in that square area. In HD they have crammed more pixels into that size allowing for more detail.
Imagine a tin of baked beans - more juice = SD, more beans = HD
No, that's not exactly what I meant. I wasn't talking about pixels, but LINES of pixels. 640 lines across by 480 lines upwards.
I have an HDMI between the HD Freesat receiver and the HD tv.
Don't know where you got 640x480 from, that's a computer resolution not a TV resolution. US TV uses 720x480 (345600 pixels) and European TV uses 720x576 (414720 pixels). HD is 1920x1080 (2073600 pixels) so its 5 times better in Europe and 6 times better in the US.
The article you quoted is for a very specific case, going from 24p to 1080i25 or 1080p25, where you are going from 24 fields a second to 25 frames a second, be them 25 progressive fields or 50 interlaced fields, with the fields making up each interlaced frame only containg the info of 1/25s, so in essence the same thing, when you add tv deinterlacing (lets forget any effects of the change in frame rate
In the real world, motion is continuous. The main difference is 1080i25 is a field rate of 1/50 and 1080p is 1/25fps. So for fast motion, or a live scene it is not a fair comparison and there will be a difference, you should really compare 1080i25 and 1080p50 so you have the same field rate per second, in which case there is a big difference
The problme with 1080i25 is a lot of TVs are still not that great at deinterlacing.
Depending on the scene, and level of motion, there can be a lot of difference between 1080i and 1080p.
I got told about the 640 lines thing from someone ages ago. I've just found out now that it, is in-fact, 720x576. High Definition can also be 1280x720 as well.
Well said.
In the case of movies and high end dramas and nature documentaries they use something called segmented frame where the frame rate is half the field rate and therefore both fields come from the same frame so its effectively a way of smuggling 25p onto a 50i standard. In the case of most other material and especially fast moving sport, the broadcaster simply throws away half the lines in the picture and leaves your telly to try and guess what information they contained and make something up, a lossy process which most TVs are quite bad at anyway.
The resolving power of the eye is expressed as angular resolution, so you can see as much detail on a 21 inch screen at 3 feet as you can on a 42 inch screen at 6 feet. Personally I see a huge difference between DVDs and blu-ray on my 15 inch laptop screen.
Well then your TV settings are crap, or your TV is crap. It's a horrid set top box too, but not for picture purposes, they are pretty much identical in that respect. What TV, and have you ever changed he settings from unpacking it? 1st thing, get the sharpness turned down. Most TVs look best with the sharpness turned to minimum, but if it gets all fuzzy, yours is an exception. All other settings at halfway and you may be close. You can get DVDs to help you get your settings right, or if you have a DVD with a THX badge on the case, it has a little easter egg in the languages section, the THX optimiser. Try it, you may be surprised.
I think he's saying they haven't done an HD transfer, presumably people think this because the films are not available on blu-ray yet, but they are shown on HD movie channels so I'm guessing they must have been scanned in HD. That's not to say that the version ITV have is necessarily HD of course.
It may be HD, but not the bandwidth we'd get on a Blu Ray disc. And of course broadcast sound is usually fairly rubbish, whereas a blu ray should be 6 channels of CD quality, or it will be if it's from Lucasarts.
However... and in the real World this is very important because many people don't realise it... from a typical seating position in an average family living room (3m - 4m eye-screen distance) you will not be able to distinguish the higher resolution of HD TV from SD TV with a 19 inch set. Human eyes are not good enough. You probably need a set twice that size or more and to see the full detail of 1080, a screen size well over 50 inches (from 3 - 4m).
Real-World resolution is a linear measure i.e. it is measured in one direction. This is how opticians, astronomers and microscopers do it and there is no valid reason why TV vendors should do it any differently. They use areal resolution only to make something that's twice the resolution seem like it's 4 times. Well it isn't. It may contain 4 times the amount of information but that is not equivalent to 4 x the (linear) resolution.
There is a very good reason why linear is the best way to compare resolution (unless you want to trick people). You can double an object size (3 ft tall becomes 6 ft tall) then move twice as far away... and you will see the same amount of detail in it. The visible resolution is the same. Conversely, if you then move to half the distance, you will see it at twice the visible resolution, not 4 times. For example, on an optician's chart... or words on your computer screen. Twice the width and height is twice the resoution, not 4x (except for digital camera and flat panel TV vendors).
Couple that with the fact that on BBC HD (among some but not all broadcasters) the broadcast HD resolution is 1440 x 1080 and you can see that the improvement in maximum resolution, i.e. with a "full HD" screen, is approximately 1440/720 =2.0 horizontally; and about 1080/576 = 1.875 vertically. On some (perhaps all?) Sky HD channels it will be a bit more, if they broadcast at 1920 x 1080.
Couple all the above with the fact that most viewers watch TV from 3m - 4m distance, their screens are typically "HD ready" and 42 inches or less and it's not hard to see why the "wow" factor simply isn't there for many people.
Yes HD is much better... you can identify an object of about half the size on BBC HD compared to BBC SD (if you are close enough and the screen's a full HD). In my book that makes BBC HD (just less than) twice as good in resolving power as SD... but claims that it's "5 x better" are no more than hype. The answer to the question in the thread title is: yes... but with the right equipment, setup and viewing distance for screen size, HD is still much better than the original poster seems to think.
You do realise that on most TVs the sharpness is supposed to be turned down as low as you can get, except on TVs where it goes below zero and actually starts softening the picture. Adding sharpness is just adding false detail to the picture that isn't supposed to be there, and it looks awful. Most people have their contrast turned up way too high as well so that detail is lost in the very bright and very dark parts of the picture. It may just be that the demo was set up correctly but that's not what most people are used to seeing. Standard definition does look particularly crap blown up on a large screen.
Rather than take some demo's word for it, try watching the same movie on DVD and blu-ray and see if you notice the difference, or try switching between the SD and HD versions of a programme being simulcast on BBC HD or ITV HD, be careful with C4HD though as some material is upscaled on there.
I got sucked in there comparing pixel count, but you're right of course - optical resolution is measured in line pairs, so line count is a more meaningful measure of display resolution than pixel count.
That's a pretty good demo of the difference, thanks.
They were using SCART sockets in some of them, which is pointless if the selling point of the TV is it's in high definition!
The same can be said for other retailers, too.
Thanks - I wasn't aware of that.
The Ad Standards lot ought to get hold of this in much the same way they've taken on broadband companies who say one thing and deliver far less. There should be a minimum bit rate below which it cannot be classified as HD.
Maybe there already is?
http://whathifi.com/News/BBC-admits-to-problems-with-new-HD-encoders/
Since then it just hasnt looked as crisp as it was.
Maybe not resolution-wise, Sid (although I would argue with that anyway), but there's a significant reduction in those horrible wiggly artefacts that SD digital suffers from. In fact they don't appear at all on HD, and this give a much cleaner looking picture even when you watch an HD broadcast at SD resolution.
yes indeed. It's perfectly possible to spot an HD broadcast even if it's via RF feed in the next room, if you know what you are looking for.
Ah, but are you talking about a Standard Definition signal being broadcast through a High Definition television though? The Standard Definition image will have to be stretched in order to fit the higher resolution.