Digital Satellite on Analog TV (1 Viewer)

[Joe Lugoff]

I'm getting my first digital TV (HDTV) next month, and I'm first learning about them, so of course I'm having a nervous breakdown.

I have DirecTV and I have a few questions about my transition. I just called DirecTV and asked technical "help," and unbelievably, they didn't have the answers. I know if anyone does it's you guys here.

My questions are:

I've had DirecTV since 1999. If I understand satellite TV correctly, it has always been digital. However, I've had it connected to an analog TV. Of course, next month, I'm connecting it to the new digital TV.

I want to know at what point is the digital signal converted to analog? Does the satellite box do that? Or does the TV do it?

If it's the satellite box, how do I get it to stop converting digital to analog when I hook up the new digitial TV?

Also, the woman at DirecTV said I won't notice any improvement in picture quality with the new digital set. Is that correct? It seems the conversion to analog must degrade the picture to some extent.

Thanks for your help!

 

[Joseph DeMartino]

The satellite box converts the incoming digital signal to analog because until a few years ago all TVs were analog, and even now most digital sets are also HD sets, and your DirecTV receiver isn't HD, so there's no point in its sending out a purely digital signal. Your outputs are probably limited to coax, s-video and an RCA video jack. If you're lucky you might have a component video output. (Analog.) You will have a digital audio output, but the image is still going to be analog.

Since you're getting a hi-def digital television, you may find your standard def signal looks worse than it did on your analog set. If you were just getting an SD or ED digital set, you probably wouldn't notice much difference. Satellite and cable signals tend to be heavily compressed. Digital does not automatically mean "better". Video CD was "digital". It sucked. Laserdisc, which had analog video, looked infinitely better. DVD is better than either, but it took more than merely being digital to do that.

If you're buying an HD set and eventually upgrade to DirecTV-HD and a new receiver, you'll see a big difference on your HD channels - but the SD channels will either look about the same or worse, depending on the source signal. That's just the nature of HDTV and SD signals, whether from cable, satellite or over the air. (Even SD DVD will look anywhere from stunning to crappy scaled up to HD, all depending on the quality of the original source material.)

Regards,

Joe

 

[Joe Lugoff]

OK, but I'm still confused on a couple of things.


Why would there be no point? Isn't there such a thing as a digital Standard Definition signal, and wouldn't it be better than analog?

Are you saying my box will still convert digital to analog? Then how will my new digital TV handle it? Convert it back to digital?

 

[Joseph DeMartino]

Yes. And if your set is a "fixed pixel" design (basically anything other than CRT - LCD or plasma flat panel, LCD RP, DLP, LCoS) it will also scale all incoming signals to its native resolution. If you're getting a 1080p set or a 720p/768p one, that's all it can display. One of the reasons SD tends to look lousy on HD sets is this scaling, which with a marginal incoming signal (like a local UHF station) is basically trying to scrape too little jam over too much bread. A line multiplier can do remarkable things (a good DVD looks almost like HD on my 720p LCoS) but when it has too few pixels to interpolated from, it can look blocky and grainy.

I should have mentioned in my first post that the other thing that makes SDTV look really lousy on an HD set is the way the TV is setup out of the box. Make sure you have a copy of Digital Video Essentials or Avia Guide to Home Theater before you get the set. You'll want to calibrate the brightness, contrast, sharpness, tint and color before you even try watching any program material on the set. Otherwise you'll be as horrified as most HDTV buyers are when they turn on that set for the first time.

Hope this helps,

Joe

 

[Joe Lugoff]

Yes, Joe, that helps a lot. At last I understand it! Thank you very much!

 

[LanceJ]

Can't Joe request a new box from Dish for his HDTV that has an HDMI output (though *its* digital output might not look better than component), or if the HDTV is equipped properly, a cable card, so that digital-to-analog conversion never occurs?

And Joe, if you don't want to spend $$ on a video set up disc right away, you can use what may be in your dvd collection already:

THX Optimizer

This contains a series of fundamental configuration screens that can really help your monitor produce a much more accurate image and it only takes about 10 minutes to use. It also has some audio tests too. It's on my Attack Of The Clones dvd, IIRC in the "Options" submenu and its icon is rather dimly lit so I have to look carefully for it.

 

[Robert_J]

Cable cards don't help in satellite situations. They only work with cable. Hence the name cable card.

-Robert

 

[Joe Lugoff]

To RobertJ:

So, if I understand correctly, prior to offering HD channels, DirecTV was offering a box that didn't convert digital signals to analog, but left them as digital?

And if I continue to understand correctly, they no longer do, because they'd prefer that people upgrade to HD?

 

[Joseph DeMartino]

I'm not Robert, but I think I have the answer.

No. Robert is saying that prior to adding a new group of many additional high-def channels, DirecTV would swap out an SD box/DVR for an HD one with relatively little cost or bother. But now that they're offering the extended HD-lineup their HD upgrades include new hardware (needed to get the extra channels) which is much more expensive.

He's talking about two HD upgrade paths, not talking about a digital SD box with an HDMI output.

As far as I know no one has ever offered an SD satellite receiver with HDMI or even DVI outputs. (I don't think there were any SD cable boxes with those connections, either.)

Regards,

Joe

 

[Robert_J]

And there's only been one SD box that had 480i component video outputs. Basically, with an SD box you are stuck with RF (channel 3/4), composite video or s-video. If you want a digital video path between your satellite receiver and your TV you need a high def box. But that doesn't improve your standard def signals. You must upgrade your programming and watch HD channels to get the full benefit.

-Robert

 

[Joe Lugoff]

Again, thanks for the clarification.

And now I have a new confusion.

I just got back from shopping for the new HDTV. I read several Internet articles before going, and felt well equipped. My understanding was that TVs can be 480i, 480p, 720i, 720p, 1080i and 1080p.

So what did I see? Several which were 900p. And the other number with it gave a ratio which, while greater than 4:3, was much smaller than 16:9. Now what's that all about?

 

[Joseph DeMartino]

That sounds very odd. These sets seem to basically be computer monitors that have a secondary use as televisions. 900 progressive line screens were common in even CRT-based computer monitors back in the old days. The aspect ratio seems to be about 14:1. Of course nothing is designed to be shown at that ratio, so everything you watched on it would be pillar-boxed or letterboxed (or cropped/zoomed) And it will have to scale all television inputs - upconverting 480i and 720p signals, and downconverting 1080i and 1080p. My instinct would be to stay away from these as they are not true HDTVs, even with 900 lines of picture info.

Regards,

Joe

 

[Joe Lugoff]

Thanks again, Joe.

I will gladly avoid those sets. After looking at the 16:9 sets, those 900p ones just didn't look really "widescreen" to me.

Here's an example of a 900p I found online:

Philips 19-Inch Widescreen LCD TV with HD Tuner : Audio & Video from Overstock.com

It's described as:

High-definition LCD WXGA+ display 1440 x 900p

That gives a ratio of 16:10, which is exactly 90% of the width of a 16:9 screen.

I wish I knew more about this, but I'll hazard a guess that WXGA is a term applied to computer monitors ...? Could these 900p sets be designed for those who intend to play video games on them?

 

[Stephen Tu]

Not really. You can break TVs into roughly the following categories, some of which are close to impossible to find in stores these days:

- old school CRTs, the TVs people have been using for decades. Essentially 480i. (in reality 525i, about 480+ visible, the rest being hidden at the edges of the set, digital video uses 480 lines to store actual picture data).

- HD CRTs, direct view and/or rear projection. Most are 480p/1080i, some are 540p/1080i, they convert 480p to 540p so they can get away using one scanning frequency, simplifying the electronics. There were like a couple model years of Panasonics that also supported 720p scan rate but were discontinued due to the extra cost. 720i is not used, it's not an ATSC format.

- ED plasmas, 480p.

- HD fixed pixel displays, flat panel (LCD, plasma) or microdisplay rear projection / front projection (DLP, LCD, LCOS/SXRD/D-ILA). All of these have an inherent native resolution you should look for, all video is converted to this format for display. 1920x1080p, 1366x768p, 1280x720p are common ratios. The non-1080p models tend to all be lumped together as "720p" sets although some stores very misleadingly call them "1080i" sets. The 16:10 ratio models you see tend to be repurposed computer monitors as that's a common ratio for monitors. I haven't really carefully researched them, I don't know if they display black bars to achieve proper 16:9 video or if the picture gets slightly distorted. Anyone know?

As for the digital/analog thing you were asking about earlier ... it's not the digital->analog conversion that kills your quality (even if multiple D->A, A->D steps), as this is fairly accurate w/ modern DACs/ADCs; most people will confirm little difference between component connections & HDMI/DVI. It's what Joseph tried to explain, that digital is no guarantee of quality. Given a certain amount of bandwidth, a satellite company can choose to use digital technology to either send few high quality, high resolution video channels, or very many low quality, low res channels. For the SD channels, they chose the latter, so they could advertise 100s of channels, and because people on the old sets weren't screaming too much about the quality.

But now people are getting much bigger HD sets, so they have to go the other way. You'll have to get a HD receiver to get those channels though, get the HD-DVR package. Or consider cable/phone company options if they have competitive offerings in your locale.

 

[Joe Lugoff]

I see these 900p sets everywhere I look. Today I saw them with the specs reading 720p, 16:9 ----- but right below, it said 1440x900, which comes to an exact ratio of 1.6, or 16:10 (which is exactly 10% less wide than 16:9, which is 1.77...:1 -- the .177... difference being exactly 10% of 1.77...).

They don't display black bars to achieve the proper 16:9 video. The picture is either distorted or cropped, I don't know for sure. All I know is I can look right at it and see it's not "wide enough," so to speak, but let's face it, the majority of people won't know or care.