2004-08-20, 02:16 AM
Is is just me or is the picture quality of digital cable significantly worse then a good analog TV signal? After watching some of the Olympics on the analog CBC/NBC vs NBC's timeshifted digital channel I can definitely say that the analog picture is *alot* more crisp and detailed. The compression artifacts on digital cable are quite horrendous if you know what your looking for. For instance a panning shot of grass (ie soccer, football) gets somewhat blurry on digital channels but remains fairly detailed in analog.
I will grant you the sound is better on the digital channels though. Perhaps my older DCT2000 is not as good as newer STB's? I'm using Samsung 50" DLP as my TV so maybe this is not very forgiving on the digital channels (not that it's very forgiving on the analog channels either though...)?
2004-08-20, 02:21 AM
It might have to do with the channels they are using for the time shifting....but I could be wrong. I prefer to watch the Western NBC and all stations for that matter. They pic. quality from the eastern channels has always been poor.
MC is crisp though, as well as the SNET stations.
2004-08-20, 05:58 AM
Shaw uses a ridiculous amount of compression on the timeshifted channels -- and I do mean ridiculous. The edge enhancement is incredible - there are huge halos around everything on the screen. With this in mind, I don't use the US net timeshifts as a standard of potential digital PQ. PQ deficiency isn't the transmission medium but rather the quality of signal which is crappified before being sent out.
I don't get many of the digital services any more. Some of the digital channels appear quite compressed (BBC, Fairchild) and somewhat crappy, but others appear much better than the analogue near-equivalent (the timeshifted sportsnets are the best example).
2004-08-20, 01:26 PM
A few years ago I returned my Rogers (now Shaw) digital box because my analog picture was significantly clearer. And, channel changes were much faster.
The last few days I have been checking out the new Motorola 6200 and 6208 boxes. I've noticed while watching action shots (Olympics) on HDTV
there is a huge amount of pixelization (is that a word?) when there is quick motion (like when a gymnast does a flip).
Is this caused by the Motorola box, the TV, or Shaw?
I'm guessing it has to do with the compression by Shaw.
This appears to be an issue with NBC (and somewhat due to the limits of MPEG compression). It has been reported by many people on the various Olympic threads in this and other forums, so you are not alone and it's not your STB or your service provider.
Although pixellation (macroblocking) is visible whenever fast moving objects appear on the screen, the Olympics appears to have "more" than we should see...
2004-08-20, 02:19 PM
I can definitely say that the analog picture is *alot* more crisp and detailed.
I would agree. On my 27 inch TV the time shifts do not look to bad, however on my 51 inch they are definately not as good as their analog equivalents.
6208 Ill wait
2004-08-20, 04:57 PM
To be able to deliver the amount of programming we demand, we have to be able to take a quality hit to be able to have the variety we enjoy.
This is the exact same difference between analog and digital cell phones. In the old days if you were at a special event where thousands of people were using their phones, you could not get a line. Now we all use these digital CMDA/GSM/TDMA phones which have crappy voice quaility, but allow several magnitudes of voice channels, and better call features.
Being knowledgable about RF and how it works, although cable companies can use lots of spectrum on closed coaxial cables, there is still a crunch to try to deliver as much as we see now. All of our signals are below 800Mhz. Satellites carry a huge advantage in spectrum, and this is why they can deliver more channels.
Dont expect to see timeshifting or any quality improvements until Shaw has a full rollout to 800 or 900 Mhz capable amplifiers and cable in all areas. I am sure it will be another "coming soon" for Shaw.
The current analog channels occupy several hundred digital channels worth of bandwidth. I dont know what the factor is, but I would imagine it is above 10.
2004-08-20, 11:54 PM
you think Shaw overcompresses their channels?
Shaw puts 8 digital channels into one 6mhz channel and the PPV Channels they put 8-9 in one 6mhz channel.
Currently all Digital channels are QAM64 whereas the VOD / SOD and Cool Tv are QAM256.