DVD playback speed?

[AndyMan 7]

I have an odd question.

Recently my 4way team came to me complaining that the DVD's I made of their practice sessions were "too fast". They said it seemed like it was in fast forward.

At first, I just thought they were joking, because they've improved tremendously over the last month or so, and I figure they really are "that fast". They insisted they weren't joking, though... They say the DVD's are about 10-20% faster than they should be.

When I watch the DVD I see about what I remember seeing when I shot it. To me, they really are "that fast".

I burned the DVD using a consumer grade DVD recorder, connected via firewire to my PC-1000.

First, does this make any sense at all? Is it likely a PC1000 connected via firewire to a DVD recorder would produce a DVD that plays 10% too fast?

Second, is there any way to verify this other than showing the DVD and my camera side by side? Is there a timecode burried on the DVD somewhere?

Thanks,

_Am

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You put the fun in "funnel" - craichead.

[FeFe 0]

why don't you just time any segment of the DVD recording and compare it to the tape TC?
I can not imagine a scerio which would allow video firewired to a recorder to be recorded slower than playback speed
may I ask if you use auto-shutter or sports shutter program while filming? high shutter speed might give you a 'faster' impression. Just a wild quess...

[phoenixlpr 0]

That sounds really interesting. Your 24 fps interlaced NTSC DV source must have been recompressed, but timeline should be the same. I guess you made an NTSC DVD from that.

[PhreeZone 15]

NTSC is 29.92 FPS, not 24.

Andy, shy of it dropping frames I don't think that the playback speed would be any different.

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[phoenixlpr 0]

Bang. My fault. Anyway NTSC DV stream -> NTSC DVD. Speed should be the same.

[yuri_base 1]

Time perception?

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[quade 3]

Quote

I burned the DVD using a consumer grade DVD recorder, connected via firewire to my PC-1000.

Not a rat's chance in hell, but . . . I guess even the rat has a 1:1,000,000 chance.

To verify the speed, have your PC-1000 shoot a wall clock with a second hand for 10 minutes. Make a DVD of that -exactly- the way you did before and see if there's any difference between the clock and a stopwatch.

If there IS a difference . . . I'd REALLY want to know and talk about it as it has USPA Nationals ramifications.

quade -
The World's Most Boring Skydiver

[DSE 3]

NTSC is 29.97FpsYou can shoot 24p and store/stream it in a 29.97 package/file, however. 24p is actually 23.976 on a PC and 23.978 on a Mac, FWIW.

Anyway, it's possible a couple things could have happened at render. If you were modifying the format, it could have been resampling frames.
You could have hada template for faster speed from a previous session.
You could have had some sort of temporal plugin
It could be that the DVD player is reading audio rate and audio from the AC3 may have been corrupted and is therefore sampled differently.
It's rare, but it *does* happen. In the broadcast forum I moderate, this has come up a time or two in the past.
With a tool like GSpot, it's easy to view the framerate of the file, but no matter what, a DVD player in the US can only read 24p, 30p, and 60ifps content. PAL players read 24, 25, 30p and 50/60i.
Some DVD players can read discs that aren't MPEG and so they'll play back strange framerates and file formats such as DivX, Xvid, etc.

[phoenixlpr 0]

Have you found the reason? Was it really faster on DVD playback?

[AndyMan 7]

I haven't.

I'm think the combination of a cloudy day and a slow shutter setting made some people in the group think it looked different, which led them to think something was wrong.

The DVD plays at the same speed as the camera.

_Am

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You put the fun in "funnel" - craichead.