[opendtv] ATSC-SD vs. NTSC
- From: dan.grimes@xxxxxxxx
- To: opendtv@xxxxxxxxxxxxx
- Date: Thu, 27 Oct 2005 10:28:51 -0700
I realize that technically MPEG-2 encoding, over MPEG-2 transport, via ATSC
(8VSB, 18Mb/s) can deliver 720x480 resolution, roughly equivalent to the
5MHz bandwidth of RS-170a analog video over analog NTSC modulation (please
correct me if any of my technical specifications are off). So why then
does the SD picture at my receiver look worse on my LCD display than NTSC
on my cheap NTSC television set? When I say worse, I mean the color is
faulty, smooth lines are jagged, there are no subtleties in blacks or
whites, and high motion and detail content breaks up and gets blocky. I
realized these are all digital compression artifacts. At worse, the NTSC
pictures are a little grainey if I use a cheap antenna. I would say it is
my monitor and receiving equipment, but I have seen the same results on two
Sony HD CRT 16:9 monitors and a Sony Plasma HD monitor as well. I used the
same to evaluate SD-Cable and SD-DBS, and drew the same conclusions that SD
over those two mediums do not look as good as NTSC.
Now on the HD side, while similar problems are seen, at least the added
detail help improve the picture over NTSC. But I don't understand why
digital SD does not look better. Again, anecdotal, so perhaps this is just
a problem with me and the few monitors/receivers I have used to evaluate.
Dan Grimes
----------------------------------------------------------------------
You can UNSUBSCRIBE from the OpenDTV list in two ways:
- Using the UNSUBSCRIBE command in your user configuration settings at
FreeLists.org
- By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word
unsubscribe in the subject line.
Other related posts:
