How was/is commercial PAL video converted to NTSC?

[deadmeow]

This is not a question on how I can do it, but rather a question of how it was done in the video tape days till now, by television networks for example.

What I mean is that I have some NTSC video tapes of BBC shows (Red Dwarf), but the originals are obviously in PAL format, and I have some NTSC DVD's from Hong Kong TVB and BBC which are originally PAL.

So how do they do such a smooth quality conversion from PAL to NTSC, as the shows retain the "soap opera" effect, and the motion is very smooth as the original (although lower resolution obviously).

[jman98]

The "soap opera effect" is caused by the shows being videotaped rather than filmed. It's not difficult to retain this through a format conversion.

Others will have to comment on how this is done properly. I have a ton of Hong Kong DVDs and the ones that I know were converted from PAL (mostly Shaw Brothers stuff, but others too) definitely do not have smooth motion. In fact, that is the giveaway that it's been converted. I have one TVB show and it's been about 2 years since I last watched it so to be honest with you I really don't remember how good the motion was on it. Many studios convert from PAL sources, which may be interlaced (ugh!), to NTSC in the fastest and cheapest way possible. Both Ruscico (Russia) and IVL (they own the Shaw Brothers catalog and other films) spent a small fortune to remaster their old films and they look great, but both are infamous for using PAL sources to convert to NTSC. In the case of IVL, they actually do have 24 fps masters and foreign licensees can request those, but for the Hong Kong market, they just do some kind of quick and fairly careless conversion from PAL sources to NTSC. Ruscico does the exact same for any NTSC DVDs they produce themselves.

[sanlyn]

I'm mostly guessing, but I think that back in the old days they would play a PAL video with a PAL device that outputs the same image size as NTSC and record it into a pro-grade NTSC device. I have VHS tapes of PBS broadcasts from the early 1990's that were clearly BBC/PAL originals. When they started using computers for these conversions, I don't know. I do recall reading way back then that many of these programs were done on film, then mastered to both PAL and NTSC from the film originals.

Maybe it's just the fact that today's HDTV's aren't as forgiving of source defects as CRT's were, but most of the BBC-to-NTSC stuff I see on TV today usually looks terrible.

[deadmeow]

Hi Jman98, when I was speaking of smooth motion I was referring to video taped sources. For film sources, I notice jerkyness on all NTSC DVD's on an LCD display. I have a hard time watching NTSC DVD's of films on LCD displays, as the motion has some glitches, so I usually prefer to rip/compress them and correct the framerate.

However, on videos that have gone from 25 to 30 fps the motion remains smooth, and the loss of quality only seems to be loss of resolution.

[vaporeon800]

"Snell & Wilcox" may be a good place to start from for your web-searching.