AVCHD files turn "interlaced" when re-saving veg

essami wrote on 4/15/2010, 10:31 AM
Hi,

This is a puzzling one. I can't recreate this at will and so far it's happened to me twice. But I would like to hear if anyone else has experienced anything similar.

A few times after editing a project with AVCHD files (from Panasonic GH1) and after saving the project with a new name (Video_edit_2.veg) and rendering out the footage to mp4 file the movement looks really videoish, almost like interlaced. I scratched my head with this for a long time and just for the hell of it tried checking "disable resample" for all clips. To my pleasure all was well again! Footage looked smooth as butter as it did before when rendering out from Video_edit_1.veg.


Anyone had this happen? Any ideas if this is a bug?

Sami

Comments

kairosmatt wrote on 4/15/2010, 11:32 AM
Sami,
What are your project settings and render settings in regards to frame rate and progressive/interlaced? And what format did you shoot the video in?

It sounds like there was something not quite matching if disabling resampling fixed it.

Does the GH1 shoot in 30 instead of 29.97 like the Canons?

kairosmatt
essami wrote on 4/15/2010, 12:36 PM
Hi,

I'm shooting 720p 50fps (I have the PAL version of GH1) and I drop of the stuff to a 720p 25fps timeline. Render to MP4 with the same settings: 720p 25fps.

Funny thing like I said, I didnt change any project settings, used the same render template. Only thing different was I saved the veg file as a new file with a different name and did a few edits here and there. Nothing major though like moving all the events to a different point in timeline etc.

sami
kairosmatt wrote on 4/15/2010, 12:50 PM
Interesting. I think it comes back to resampling. Make sure that it is off and Vegas should just skip every other frame. Or set your playback to .5 for slow mo. But I think the key is to disable resampling.

Just out of curiousity, if you are playing it at 25p normal speed, do you add any motion blur to compensate for the 50p? I have been playing with this a little, but don't have any good answers to what the best recipe is. Thoughts?

kairosmatt

farss wrote on 4/15/2010, 2:48 PM
If you're shooting 50p to deliver 50i you really do need to watch your shutter speed. Also in progressive scan some cameras can deliver too much vertical res for interlaced video and you really do need to wrangle this, sometimes a LOT.

Still doesn't address the real issue here, why is Vegas not being consistant.

Bob.
kairosmatt wrote on 4/15/2010, 4:15 PM
I think the inconsistency is with smart resampling. I have noticed this before too, going through frame by frame it will sometimes give different results.

Turning it off, or forcing it-if that's what you want, is the best way to do it.

kairosmatt
essami wrote on 4/16/2010, 12:13 AM
OK, good to know I'm not the only one seeing this. I shoot 1/50th shutter. I never use any motion blur or anything and Ive been real happy how the footage looks.

www.samisanpakkila.com