[QuadList] DVD vs Blu-Ray

[James Snyder]

Steve,

Strictly speaking, no DVD can be "NTSC" since NTSC was the 525 line 
analog television standard and DVDs are, by their nature, digital TV 
delivery media in the 480 line format in the former "NTSC" countries 
(using MPEG-2 video compression), and 576 format in the former PAL & 
SECAM countries.  However, "NTSC" has become a colloquialism for "480 
line video" and is thus misused constantly.

The difference between NTSC and 480 being that, since digital signals 
don't need horizontal or vertical blanking intervals, the extra lines 
used for those timing signals for analog CRTs are not included in 
digital video.  There were 45 lines of blanking in NTSC.  Same with 
576:  the H and V blanking lines in 625 line video aren't needed in 
digital TV and are thus not included in the digital signals.

DVDs have the ability to reproduce 16:9 (1.78:1) aspect ratio video, 
so if the people on your Garth Brooks DVD don't look squished, most 
likely the video was orginated in 16:9 480 line digital video.  I 
can't imagine anybody creating anything in actual NTSC analog today. 
It would look like crap with all the analog artifacts.

Hope this helps,

James
------------------------------------------------
James Snyder
Senior Systems Administrator
Library of Congress -
   National Audio Visual Conservation Center (NAVCC)
Motion Picture, Broadcasting & Recorded Sound Division (MBRS)
Packard Campus for Audio Visual Conservation
http://www.loc.gov/avconservation/packard/



>Thanks for the opportunity to ask, can someone help me get a better 
>grasp of DVD vs Blu-Ray formats?
>
>I recently received a video disc labeled as an NTSC DVD of the Garth 
>Brooks "Blame It All On My Roots" performance in Las Vegas. 
>Playback on my Blu-Ray deck displays as full screen on a new 
>Panasonic plasma screen capable of 1080p without obvious aspect 
>ratio distortions.
>
>Garth's performance is incredible; lighting, camera work, audio, 
>direction all are great.  Apparently, there is currently no Blu-Ray 
>disc available.
>
>- Is it technically correct to label the DVD as NTSC when the image 
>displayed is 16:9?
>
>- What's the likely resolution/format?  Any suggestions on how I 
>could have confirmed that without asking you?
>
>Many thanks,
>Steve
>
>