Re: analog or digital - Let me know!

hociman — Thu, 04 Jun 2009 02:23:48 GMT

NTSC is a format. It's a format with 525 lines per frame, using interlacing over two (2) fields per frame to display the information, with 29.97 frames per second. Only 480 of these lines in each frame are visible. SD-SDI (SMPTE 259M-C) is a format used to convey NTSC information with a digital signal, while digitizing video in the component domain.

I think you are being shorsighted in thinking that NTSC is analog, and that SD-SDI is something else. If its not 480i/525i, then its not NTSC. If its 480i/525i, then its NTSC, whether its composite, component, or component digital. It just so happens, through marketing or otherwise, that we all associate NTSC with SD.

If there is anything that bothers me, its when I see tapes labeled NTSC HD. There is no such thing. It's called ATSC.

-Jonathan

analog or digital - Let me know!

markbulla — Wed, 03 Jun 2009 17:13:17 GMT

Hi all - just a little venting...

I'm getting a bit tired of people using "SD" and "NTSC" interchangeably to mean either NTSC analog or SD-SDI, and then not specifying which one it is. We regularly get satellite downlink information in that has both an HD feed and an "SD" feed listed - half the time the "SD" feed is analog, half the time it's digital, and we have to do detective work to figure out what they are trying to tell us.

Another case that I recently ran across, in an ad for a computer based waveform/vectorscope, one of the "Supported Video formats" that they have listed is "525i NTSC". The problem that I have with that is that the unit only has an SDI input... Am I wrong in thinking that NTSC is an analog format? If they are just using "NTSC" wrong, shouldn't it be 480i? (It turns out that the system will accept SD-SDI (SMPTE 259M-C) and HD-SDI (SMPTE 292M), but the support guy didn't seem to understand my confusion...)

I hate having to guess at this stuff, or try to take into account every possibility.

Thanks for letting me get this off my chest!

Mark

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Re: analog or digital - Let me know!

analog or digital - Let me know!