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Hello everyone, i just joined and before i spend my hard earned cash on my first big tv, i was hoping someone would give me some advise. I am interested in a Panasonic TH-42PX7B. Would you recommend this plasma? Is there much difference between this and the Panasonic TH-42PX70?

Any infomation or advice would be greatly appreciated. Thanks.

 

[professorhat]

Hi there and welcome to the forums! Thought I'd have a quick look into this for you, I'm not familiar with either of the TVs personally, but, from this is I can see from Panasonic's website:

The TH-42PX7B has only one HDMI socket, no PC input socket (i.e. the VGA plug like on the back of a computer monitor), a resolution of 1024x768, a contrast ratio of 8000:1 (that's the ratio between the brightest whites and blackest blacks) and can be found for about £700 here and there.

On the other hand, the TH-42PX70 has two HDMI sockets, a PC input socket, the same resolution of 1024x768, a contrast ratio of 10,000:1 and is generally available for the same price. It was also awarded "Best Budget 40-42in TV" in What Hi-Fi's Awards 2007 issue. From what I can see, they haven't reviewed the TH-42PX7B.

On the above basis, I would get the TH-42PX70. It has more connections into it, a higher contrast ratio and the backing of What Hi-Fi for the same money, so seems like a no brainer to me! However, if you want to be safe, you could always demo both and see if the TH-42PX7B has a startling better picture. I'd be very surprised though!

[Post edited on 3rd Feb to remove 720p and 1080i compatibility statement due to all the malarky below!]

 

[Anonymous]

Thanks for the imformation. I think i'll head out and see if i can check them in the flesh. From the reviews on the 70 looks like i might be leaning that way already. Cheers.

 

[Anonymous]

[quote user="professorhat"]The TH-42PX70 has... a resolution of 1024x768 (i.e. 720p or 1080i compatible)[/quote]

Professorhat why do you imply that, because the tv has a resolution of 1024x768 it is therefore 720p or 1080i compatible, but you do not mention the fact that it is also just as compatible with 1080p as it is with 1080i? Why did you miss out on listing it's 1080p compatibility?

 

[professorhat]

As a TV with a maximum resolution of 768 lines could not display 1080p given it only has 768 vertical lines...

 

[Anonymous]

[quote user="professorhat"]As a TV with a maximum resolution of 768 lines could not display 1080p given it only has 768 vertical lines...[/quote]

No professor you have missed the point. It was you who said that the tv is 720p and 1080i compatible. But just as you have said, because of the tv only having a 768 line resolution (1024 x 768), it can't display 1080p - nor can it display 1080i, so why did you say that it is 1080i compatible?

Basically you have said in your post that it can't display 1080p because it only has a resolution of 1024 x 768 but in your original post you said that it could display 1080i, which is just as impossible as displaying 1080p on a screen with a resolution of 1024 x 768. However, if what you infact meant was that the tv is capable of accepting 1080i and then downscaling it to suit the set's 1024 x 768 resolution, then why did you not also say that it is capable of accepting and downscaling 1080p?

Have a word with yourself mate.

 

[professorhat]

Hi Ben!

Okay, for some reason, we seem to have got off on the wrong foot. My post was designed to be helpful to a new comer to the forums. Basically, I'm not a technical person, so I can't give you the exact technical reasons why what I say is true. However, I do know, that in order to display a native 1080p output, a screen must have at least 1080 vertical lines i.e. in general this means the resolution of the TV is 1920 x 1080 (or more) and is termed a "Full HD" set or "HD Ready 1080p" set.

1080i is different. I know the "i" stands for interlaced and this means that the TV updates every other line every 50th / 60th of a second (depending on the frequency of the signal / television you are watching). Then it updates the line it didn't update last time a 50th / 60th of a second later. In this way, a picture is produced and, because of the human eye's limitations, we barely notice this (if we notice it at all). With the "p", (which stands for progressive) every line is updated every 50th / 60th of a second, in theory giving a smoother picture (I say in theory due to the human eye's limitations, therefore, not everyone would actually be able to see the difference. Generally, the bigger the set, the more noticeable it is, which makes sense).

Now this is where my technical knowledge gets hazy, but my practical knowledge stands up and shows my original answer to be correct. I know my Panasonic television has a resolution of 1024x768 i.e. the same as the two televisions the man / woman posted about. I also know from use, that my television is natively compatible to display 720p and 1080i signals, but cannot natively display 1080p signals and has to descale them to one of the other formats. Having done a little research on the TVs the original poster asked about, I was then able to tell him they did the same.

Personally, I don't know why this is the case (though I can guess it has something to do with the image being interlaced rather than progressive), but I can tell you it's true. Therefore, the two televisions he was asking advice on can natively output 720p or 1080i signals, but cannot output 1080p signals.

Now, I'm never a man to not admit I'm wrong if proved otherwise, so if you know different, please explain this rather than just saying I'm wrong and not giving any evidence to show this!

I hope this clears this all up, and if I am wrong, I'm happy to be educated and also for the poster to be shown the correct information too. As I say... I was only trying to help!

 

[professorhat]

Okay, so now I've read a few articles, I think what you were trying to say is, why did I say the TV was 720p and 1080i compatible (and not 1080p) when it only has a resolution of 1024x768 and therefore can't natively display 1080i. And you're right, that was perhaps misleading for someone that knows what all these things are, but I was trying to make it as simple as possible!

So, for clarity. The TVs can display a 720p signal (be that from some HD video source, maybe Sky HD or a gaming source like PS3 or Xbox 360) and that will display natively (on my Panasonic, a little information bar comes up and tells me it's outputting at 720p).

The TVs can display a 1080i signal (from all sources as before) but a certain degree of descaling / conversion will happen on this signal as the TVs cannot display 1080 lines (being as they have 768 maximum). However, in terms of most people, this is a native display (and in fact, on my Panasonic, a little information bar appears at the top to tell me it's outputting at 1080i).

At 1080p, on all the TVs mentioned so far in this post, this can obviously be displayed, but not at the native resolution output from the source. The TV thus has to convert this down to either 1080i or 720p so it can display the lovely images coming from your PS3 / Blu-Ray player / HD-DVD player. (In this case for me, my Panasonic displays a little information bar to tell me it's outputting at 1080i as that's what I have it set to do. You could also choose to do this 720p if you wanted I think).

So there we have it I think. A relatively simple post turned very complicated. Hopefully the original post made enough sense that anyone who either doesn't understand or (understandably) doesn't care about all this can still make an informed decision!

 

[Cofnchtr]

Hi,

I don't know which Panasonic you have professor, I have a Panasonic TH42PX70B TV and when I watch bluray from my PS3, I get a little information bar saying 1080p.

My TV will accept a native 1080p signal but will down convert it to fit the screen resolution of 1024 x 768.

The same as it will accept a 1080i signal from my SKYHD box and after some internal jiggery pokery, will display it on my screen. I wouldn't call it a native 1080i (or native 1080p) picture though - in both scenarios it's a 1080 picture (at source) processed to fit my screen.

While playing a PS3 game, the infobar will display 720p as this is how my games (so far) have been sent from the PS3. I don't know of any 1080 (i or p) games for the PS3 but that's not to say there aren't any out there.

As far as I am concerned, my TV will display a native 720p signal but anything higher is not native, it's processed.

To answer the original post, the TH42PX70B is a better choice with more sockets and higher specs as you have already said.

Cheers,

Cofnchtr

 

[Anonymous]

Professor, the tv in question (Panasonic 42PX70) has, near enough, a native resolution of 720p. This means that the only format it can display natively is 720p. You say that it can display 1080i but with "a certain degree of descaling / conversion." This is exactly the point! The fact that the tv has to scale the 1080i picture in order for it to fit the screen means that it is therefore not able to display 1080i natively.

So, just to clarify, when the tv is being fed with 1080i material, the tv has to downscale it to 720p (which is the screen's native resolution). This means that the tv is absolutely not displaying 1080i content natively.

With 1080p content, just as is the case with 1080i content, it has to be scaled to fit the screen. Therefore it has to be downscaled to the screen's native resolution which is 720p. If, like you say, the tv converts a 1080p feed into 1080i then it still would not fit the screen.

To recap, the tv has a native resolution of 720p. This means that both 1080i and 1080p need to have exactly the same amount of scaling to fit the screen's native resolution of 720p.

One other thing, at the risk of creating more confusion - 1080i feeds actually need more conversion / processing because as well as the downscaling, they also have to be de-interlaced before they can be displayed by the the natively progressive tv.

Anyway, if someone can actually understand what I have said (because the professor thinks that everything has to be simple otherwise the masses are just too slow to understand

) then please back me up.

 

[Anonymous]

[quote user="Cofnchtr"]
My TV will accept a native 1080p signal but will down convert it to fit the screen resolution of 1024 x 768.

The same as it will accept a 1080i signal from my SKYHD box and after some internal jiggery pokery, will display it on my screen. I wouldn't call it a native 1080i (or native 1080p) picture though - in both scenarios it's a 1080 picture (at source) processed to fit my screen.

[/quote]

Nice one Cofnchtr. The last thing I would want to do is patronise you, but you are 100% correct and you have probably explained it better than me. Cheers mate. I've never heard of anyone with the same as you before!

 

[professorhat]

Blimmin' heck, I didn't know I was going to start all this when I first posted!

Anyway, I can see your answer is right now - I've heard it and it makes sense and as I say, I don't fully understand everything that's going on technically with my TV when it's displaying 1080i. I think the point I was trying to make was, if I use my PS3 to automatically detect my TV's maximum resolution (a Panasonic TH-42PX600B by the way), it tells me this is 1080i. It might not technically be true, but it makes sense (in my mind anyway) to say therefore that my TV is 720p and 1080i compatible (as this is the maximum resolution it is capable of outputting according to my PS3). This also means a non-technical person (who generally doesn't really care what the TV is actually doing) wouldn't buy the TV thinking they can output 1080p natively on it (as this just wouldn't be true). As I say, I realise now that saying it was "720p and 1080i compatible" was misleading and I have edited my original post to remove the compatibility statement. Hopefully you can see where I was coming from when I wrote it, and it was genuinely meant to be helpful, it's just my choice of wording was definitely suspect in my original post and subsequent posts e.g. saying "natively display 1080i" was incorrect and not really what I meant.

Hopefully we can put this to bed now, since hopefully it's agreed on which TV the original poster should go for and the reasons why, which in the end was what the original poster actually wanted to know!

 

[Anonymous]

Professorhat we were not talking about your tv.

We were talking about the Panasonic 42PX70, which is natively 720p. Therefore the only picture that can be displayed in it's native form is one with a resolution of 720p. Both 1080i format and 1080p format pictures will equally be accepted by this tv, and will undergo an equal amount of scaling. Therefore it is not appropriate (or correct) to call this a 720p / 1080i tv. You could call it a 720p tv. Or you could say it was 720p / 1080i / 1080p compatible. But not 720p / 1080i compatible and leave out the fact that is just as compatible with 1080p as it is with 1080i.

We were not talking about your tv! We were talking about the Panasonic 42PX70.

 

[professorhat]

I know, I know! That's why I said you were right and edited my original post to remove what I said - I was just trying to explain to you why I wrote what I wrote.

Hopefully, as I say, we can now leave this post to rest