I've never worked with NTSC footage, so I'm not very educated about this television standard. I have few questions...

I have an uncompressed RGB QuickTime video file in PAL (25i upper fields first) that I have to convert to uncompressed RGB NTSC QT file. This file is going to be outputed to NTSC Digital Betacam tape. As I'm not going to do the outputing-to-tape process, I have no idea what editing system is going to be used, so I must convert the video to simple uncompressed video file that can be used in any editing software.

I know that NTSC have two resolution standards - 480-line (for DV and DVD) and 486-line for the rest of digital SD formats.

So, I guess that for outputing to DigiBeta I have to set the outputing resoluton to 720x486. But what about field ordering? In PAL everyting except DV25 and in some cases DVD uses lower fields first and the rest of the formats are upper field ordered. What happens in NTSC case? Should I leave field order as it is (upper) or convert to lower? And what about converting the same file to NTSC MPEG2 for DVD? I know I have to use 480 lines in this case but what about field ordering?

And one more thing - what about black levels in NTSC? If I use Avid software Y waveform monitor (in Colour correction mode) as reference, at what value should the black lie in NTSC project?

And the last question. If 720x480 is standard for NTSC DVD (which is MPEG2), is the 480 line standard used in other MPEG2 based NTSC SD formats as well (MPEG IMX, Betacam SX etc)?

Thank You!