Mixed Media Aspect ratio problem

BPB wrote on 4/15/2007, 6:37 PM

Hi all,
I'm working on a rock video which will be used in I believe a DIVX converted form for Clear Channel, Billboard etc streaming.
The requested format is 720X486 AVI.

My source footage is a
1) venue dual cam 720x480 ..the best footage and 70% of what I'm using.
2) 3 mini DV cams that are 4x3 ratio...I'm pan cropping them to mix with the venue footage
When pan cropped to 720 width maintaining aspect ratio...the height comes out at 368.2

I've over come some of what I call a fringing problem...a glow around the edge of the screen when fading from the venue cam to the mini dv by making sure the venue cam is faded to black when i make the cut (is this a proper way to handle this?)
I've applied color correction to the mini dvs

My 3 main problems
Is there a way to get to my requested ratio of 720 x 486?
Is there a way to get my mini dvs to match better?
And alarmingly when I rendered to AVI 720x 480 my mini DV footage has mucho zippering distortion (my description) on movement ..ie zig zag edge distortion on the performers as they move.
I did a render to 320x 240 wmv to preview to projected output and the zippering (what is this really called?) is much less noticeable..but still bothers me.
I am a guitarist not an experienced editor , though i have edited successfully several dvds and commercials, albeit with better stock footage and in 4x3.

Thanks for any help...I leave for Nashville on tues for a recording session (audio engineer hat)
and would like to put this to bed tomorrow..so thanks in advance for your rapid replies.
Musically and visually yours,
Bryan

Comments

dsf wrote on 4/15/2007, 8:00 PM

The "zippering distortion" sounds like interlace. You could try going to File>Properties>Progressive Scan. That might help. Sorry I cant help on the other problems. I think someone more knowledeable will answer you.

BPB wrote on 4/15/2007, 9:01 PM

thanks dsf, i'll look at that setting.
bb

Laurence wrote on 4/15/2007, 9:39 PM

You don't have a deinterlace method selected. You need to select one when you do any kind of resize with interlaced footage.

What you're seeing is a resized interlace comb. What's happening is that Vegas is treating the two fields of your interlaced footage as a single progressive frame, cropping the top and bottom 60 pixels and stretching the middle 360 to 486. As it's doing this, the interlace comb along the edges of the two fields is being stretched as well. Yeah it looks pretty terrible, especially on any kind of fast horizontal motion.

The way to fix it is NOT to set the properties to progressive scan. Yes that will fix it, but you'll lose about half your resolution. What you need to do instead is merely select a deinterlace method (interpolate or blend fields, it doesn't matter). What this will do is let Vegas know that it needs to resize the two fields of the 4:3 footage separately as it crops the top and bottom and stretches the middle to a 16:9 aspect ratio.

Chienworks wrote on 4/16/2007, 4:46 AM

I'm slightly confused here. You say When pan "cropped to 720 width maintaining aspect ratio...the height comes out at 368.2" and it looks like you're referring to the 4:3 MiniDV material. I don't understand why this should come out wider and shorter. It almost sounds like it's actually 16:9 rather than 4:3. If it really is 4:3 then adjusting 720x480 to fit 720 wide would result in 480 tall. The only way to get 368.2 out of it is if it's actually 16:9.

There are several approaches to the fringing problem. You could use some sort of background texture behind those clips to fill in the space. Or even use some of the other material behind it so that you see things like feet moving at the bottom and stage lights at the top. Perhaps convert the top & bottom fill to be B&W or crank the saturation way up to make it look artsy. Be creative in your choices and it can be quite effective.

Always cutting at a fade to black can kill the movement and may be perceived as very slow by the audience.

BPB wrote on 4/16/2007, 8:40 AM

Laurence and Chienworks,

Thankyou for your help,
Laurence, thanks for the accurate description of the de interlace problem , I will select a method and rerender.

Chienworks, you are correct..when I looked at the properties of the media in the pool my mini dv footage says 720x480x24 with a pixel ratio of 0.9091 ntsc dv

My Main camera footage says 720x 480x24 with a pixel ratio of 1.2121 ntsc dv widescreen.

I assumed incorrectly 4x3 due to the much smaller width.

I am not using a master track, just using points on the composite level line to fade and cut between tracks..I've minimized the fringing my making sure all unused tracks are faded to black as I change cameras. To clarify my fade to black ..it is not visible (only on the extreme edges)...I am actually cutting right to anpther camera.
Thanks for your help.
Bryan