24pa mis-identified as 29.97i at DVinfo.net

Seth Bloombaum · September 14th, 2009, 04:14 PM

I've been avoiding shooting in 24p - prefer better temporal resolution and such.

However, I was shooting for a friend's project at a bicycle race, and he's all about 24p for this stuff.

Shot with my Sony HVR-V1u, set to HDV-24pa (the mode that starts each clip with a fresh pulldown cadence). (Sony's approach is to add pulldown and record in a 1080-60i stream)

Ingested using Vegas Pro 8.0c, using Vegas' internal HDV capture app, with "enable hdv scene detection" checked.

Most of the clips are fine, and play perfectly from the timeline at full framerate best/full in a 24p project. about 7 of them don't. These play at about 8fps, and show motion ghosts.

After some tracking through clip properties & such, I realized that Vegas is identifying these clips as 29.97 interlaced. Resetting them to progressive-none in properties helps some with playback rate, but still have motion ghosting & excessive judder & such. The "good" clips are all correctly identified as 24p, and play beautifully.

I'm about to try some recaptures, but was wondering if anyone else had run into this, and what their solution was? Is there a way to rewrite the framerate in the m2t header?

To forestall questions - yes, the cam was set up properly for 24pa. No, the camera settings for these clips didn't change at all. The "problem" clips are scattered through the tape...

Seth Bloombaum · September 14th, 2009, 04:56 PM

Update - the second capture run - same result, bad clip.

Third capture run - all is correct, clip ID is 23.976fps like it should, working much better now, but why???!!!

Don Bloom · September 14th, 2009, 07:21 PM

computers. can't live with 'em, can't live without 'em.
nothing more to say. ;-)

Seth Bloombaum · September 16th, 2009, 09:41 AM

Well, the pain continued, but is over now.

I ended up having to recapture about 8 out of 44 clips. Recapping took 1, 2 or 3 attempts before Vegas saw the clips at 24p. This ended up being perhaps 2.5 extra hours of work.

I'm still interested to troubleshoot. Is anyone using this basic and default workflow that is having this problem with Sony's HDV-24p? Anyone definately NOT having this problem?

September 14th, 2009, 04:14 PM	#1
Seth Bloombaum Inner Circle Join Date: Sep 2003 Location: Portland, Oregon Posts: 3,420	24pa mis-identified as 29.97i I've been avoiding shooting in 24p - prefer better temporal resolution and such. However, I was shooting for a friend's project at a bicycle race, and he's all about 24p for this stuff. Shot with my Sony HVR-V1u, set to HDV-24pa (the mode that starts each clip with a fresh pulldown cadence). (Sony's approach is to add pulldown and record in a 1080-60i stream) Ingested using Vegas Pro 8.0c, using Vegas' internal HDV capture app, with "enable hdv scene detection" checked. Most of the clips are fine, and play perfectly from the timeline at full framerate best/full in a 24p project. about 7 of them don't. These play at about 8fps, and show motion ghosts. After some tracking through clip properties & such, I realized that Vegas is identifying these clips as 29.97 interlaced. Resetting them to progressive-none in properties helps some with playback rate, but still have motion ghosting & excessive judder & such. The "good" clips are all correctly identified as 24p, and play beautifully. I'm about to try some recaptures, but was wondering if anyone else had run into this, and what their solution was? Is there a way to rewrite the framerate in the m2t header? To forestall questions - yes, the cam was set up properly for 24pa. No, the camera settings for these clips didn't change at all. The "problem" clips are scattered through the tape... __________________ 30 years of pro media production. Vegas user since 1.0. Webcaster since 1997. Freelancer since 2000. College instructor since 2001.

September 14th, 2009, 04:56 PM	#2
Seth Bloombaum Inner Circle Join Date: Sep 2003 Location: Portland, Oregon Posts: 3,420	Update - the second capture run - same result, bad clip. Third capture run - all is correct, clip ID is 23.976fps like it should, working much better now, but why???!!! __________________ 30 years of pro media production. Vegas user since 1.0. Webcaster since 1997. Freelancer since 2000. College instructor since 2001.

September 14th, 2009, 07:21 PM	#3
Don Bloom Inner Circle Join Date: Jan 2003 Location: Chicago, IL Posts: 6,609	computers. can't live with 'em, can't live without 'em. nothing more to say. ;-) __________________ What do I know? I'm just a video-O-grafer. Don

September 16th, 2009, 09:41 AM	#4
Seth Bloombaum Inner Circle Join Date: Sep 2003 Location: Portland, Oregon Posts: 3,420	Well, the pain continued, but is over now. I ended up having to recapture about 8 out of 44 clips. Recapping took 1, 2 or 3 attempts before Vegas saw the clips at 24p. This ended up being perhaps 2.5 extra hours of work. I'm still interested to troubleshoot. Is anyone using this basic and default workflow that is having this problem with Sony's HDV-24p? Anyone definately NOT having this problem? __________________ 30 years of pro media production. Vegas user since 1.0. Webcaster since 1997. Freelancer since 2000. College instructor since 2001.

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