Hi

A simple question -
Is a standard definition digital signal from a STB less than a good quality analogue signal?

Earlier this year got a standard definition STB - the sound was nogo replaced it with same model. On both occasions I wasn't impressed resolution when compared to a good analogue signal. Having two boxes of the same visual quality rules out it the STB.

I've seen the postings like ..........
SD is better than analogue because:
-Widescreen content
-No ghosting
-Crystal Clear picture (unless you watch skycam but that's a different story)
-CD Quality Sound
..........there's no mention of resolution there

Then there is
- x lines this way across & so many lines vertical in comparing standard definition versus analogue.
**lines this way and that way, defines capabilities not actual usage
-its like DVD qualtiy.
** I don't use DVD so that comparison is not informative.

All things being equal, the pic from the STB will atleast be the same as your analogue (if you have really good analogue reception that is), but will usually be better. How you attach your STB to your TV makes a fair bit of difference as does the quality of the box itself.

If you are not using s-video, component or RGB + digital audio, your Picture & Audio will only slightly better than that of a really good Analogue signal.

Note - standard "old style" 4:3 is actually REDUCED IN RESOLUTION on digital (thanks to the BASTARDRY of boxing it into a 16:9 frame rather than just sending it as 4:3).

However, the improvements the digital offers on the image reproduceablity side pretty much offset the resolution loss (unless the digital signal is being bandwidth starved to multichannel 100 channels of crap!)

Yep, was about to say kind of what Santa said.
If you watch TV in letterbox mode, then the STB has to throw away one line in every 4 to aspect correct the 16:9 for your 4:3 TV. This thus lowers the vertical resolution of the image somewhat (lowers the number of horizontal lines with information in them).
However, if you 4:3 Centre Cut the image, or 4:3 Pan And Scan (different terms to describe the same thing), then you will get full vertical resolution, but you lose out a bit in the horizontal direction (as the STB slices perfectly good image off from the 720 pixels and then stretches the result).
However, this may not be so noticable, because only very good TVs will 100% resolve the 720pixel resolution on a horizontal line anyway, so resolution loss by doing centre cut isn't so bad as losing resolution with letterboxing.
However, centre cut comes at a cost... I would never want to do this on a widescreen image, as you are slicing off perfectly good picture off the sides. You would only do this on pillarboxed broadcasts (well, I only do this on pillarboxed broadcasts, but I am lucky, as my 4:3 TV supports vertical squishing of a 16:9 image to maintain full 16:9 resolution in widescreen mode).

Regards

Not really. From a horizontal POV, in Australia's PAL colour TV system, you couldn't send 720 across the air in a blue fit. Then there is the problem of your TV set's CRT and video amps, colour trap etc etc. Odds on even if you plug s-video direct into the TV you won't be able to resolve more than ~500 dots (even on a modern set), unless its a really big TV. So put your box into centre cut mode (544x576 effectively) will give you excellent picture quality. We are talking about 4:3 after all, if its 16:9 then you have to make a choice to centrecut or letterbox, either one will drop some part of the 16:9 picture.

Infact, if you are watching analogue right now, you are probably seeing 544 x 576 (esp if you live in regional Australia and the station also has a digital service as the local analogue is usally derived at the TX site from the 16:9 transmission anyway, ABC and SBS excepted).

Is not analogue basicly an over the air "composite" video feed? Subject to similar artifacts and restrictions as composite video? (dot crawl etc?)

As for analogue vs digital there is no comparison. I can't "comment" on your STB's but on GOOD SD shows (often HD downconverts) you should be seeing noticably improved detail over DVD movies. If not your STB or display is not resolving enough.

Yes, but with added interferance & Audio included into the signal

All,
What has been omitted here is the complete absence of noise (grain) and ghosting very close to vertical edges in the picture are removed. These ghosts are usually produced in the antenna system.

AlanH

A fact often forgotten when people insist you will get a better picture using s-video, or component video connections, instead of composite. If the TV is crap, then NOTHING is going to make it good.

BTW: one very important part of a TV (included in your etc etc) is the power supply. Many, maybe even most, of the consumer grade rubbish TVs being sold are incapable of producing a decent distortion free picture, with visible recovery times after a bright object on the screen, and actually image bending due to the raster not being straight when a bright object steals the inadequate power.

Almost every CRT TV I have ever watched stretches/shrinks at the edges when more voltage is used/dropped, it's pathetic. Do any non-CRT displays do this? Also that is true about the quality of the TV overriding the quality of the connection. I've heard that with some TV's using S-video or component has almost no effect on picture quality.

Regarding picture quality of digital FTA, I have noticed 3 examples which result in poor picture quality (this is on SD using component video).

1. Live broadcasts look definitely worse on digital. There is no doubt about it!

2. Broadcasting suites using analogue source material and/or connections with analogue artefacts recorded on to the material (eg. dot crawl, colour bleeding) look much worse on digital eg. NINE NEWS ADELAIDE!

3. Fine contrast and shadow detail is lost and reveals large mpeg pixels!


This is comparing it to my analogue reception which is very clear. If your analogue reception is poor then of course digital beats it in all of the above situations

Sorry, I'd have to disagree. Many live broadcastes (eg AFL) look better in widescreen digital. In some cases this is their native format - ie digital cameras are being used for the source....

No way man!

Ch 9 and 10 live AFL, NRL, V8's, Australian Idol Live all look like utter crud! Just look at the crowd ffs they are a scungy mass of artefacts! What size TV are you on? If I switch to 16:9 letterbox on my 4:3 TV it improves but only 'cause it's a lot smaller.

Ch7 seems to do better quality live stuff I've noticed.

All I know is I'm looking at NRL live on ch9 digital, then I switch over to analogue and all the mpeg scunginess is gone. I don't think the use of digital cameras has anything to do with it, it is because they have to encode mpeg in real-time and must use a faster, lower-quality encoder.