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Old 14-07-2013, 15:32
Nostlagic
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I was wondering about American shows released here on DVD in PAL, would that be converted from NTSC and result in loss of picture quality? As i know PAL has a better picture than NSTC, but is it important to stick to the original native format?
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Old 14-07-2013, 16:18
grahamlthompson
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Depends on what the source is. If it's a movie the source is a frame of film with a much higher resolution than either PAL or NTSC. Film is normally 24 frames/second much closer to PAL25.

The scanning process for NTSC needs to produce 29.97 fps at 720 x 480 pixels. For PAL it's 720 x 756 at 25fps. The datarate is the same for both.

30 x 720 x 480 and 25 x 720 x 576. 10368000 pixels/second
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Old 14-07-2013, 23:53
Kodaz
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The frame rate is a big issue. Everything else being equal, something's always going to look best played back at the original frame rate- converting to a different frame rate that's not an exact multiple (e.g. 30 to 25 or 24 to 30) decreases motion smoothness.

As far as cinema films go, they're recorded at 24 fps. Since this is only slightly different from PAL's 25 fps, they're normally just speeded up slightly for that system (sometimes with the audio corrected back to its original pitch to compensate for the semitone increase that the speed difference causes).

OTOH, NTSC is 30 fps which is too big a difference to be dealt with that way, so they have to use a process called 3:2 pulldown. This can add a slight judder to motion. (Not that 24 fps cinema films are particularly smooth anyway, but this is on top of that).

In this case, PAL should be smoother and better if you're happy with the speed difference.

OTOH, if the material was shot at 30 fps (or 60 fps interlaced) for US *television*, it's going to look better at 30fps, and probably juddery if converted to PAL 25 fps. I don't know how many US shows were shot at 30/60 fps. British TV will look better at 25/50 fps (i.e. on its native unconverted PAL format).

Material which was (e.g.) converted from 24 fps film to 30 fps NTSC, then to 25 fps PAL is going to look awful, with two conversions, but they shouldn't be doing that(!)

Remember that some DVD players will "helpfully" convert imported NTSC DVDs to 25 fps PAL resolution on the fly, (which can make them look juddery if you don't realise why) if it's set to output PAL all the time (you can normally change this).
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Old 20-07-2013, 23:44
cornishpasty1
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This is only an issue with shows made on tape but strangely my set of NTSC Frasier dvd's don't look anywhere near as good as my sons R2 PAL collection
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Old 21-07-2013, 15:18
Kodaz
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This is only an issue with shows made on tape but strangely my set of NTSC Frasier dvd's don't look anywhere near as good as my sons R2 PAL collection
Perhaps they were mastered differently. Are they different issues?

Going by its era, I'd assume that Frasier was one of those "shot on film but edited and mastered on video" shows.
(The latter not being an issue at the time since the loss of quality due to NTSC video would have happened when it went through the analogue US broadcast system anyway, but looks a lot worse by today's standards).

One could in theory get better quality by remastering from the original source film, but I don't know if they've done that for any of them.
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