random events appear "strobish" on TV

dmcmeans wrote on 1/21/2003, 3:06 PM

I have a project that pulls in video from 4 cameras. I've interwoven clips from each of the cameras on the timeline. When I preview and when I view on computer, everything looks fine.

But when I view on my TV, certain clips look jerky or strobish. The effect is limited to the event. I thought I had some bad captures, but recapturing did not change anything. I get this effect on various events regardless of which camera they came from.

I see this behavior under VV 3.0 and under 4.0 Beta. There aren't any effects applied to these events. All effects are at the track level and all my events are on the same video track.

Anyone seen anything like this?

David

Comments

rextilleon wrote on 1/21/2003, 3:23 PM

Is this before rendering--if it is then it is fairly common on an external monitor--it wont appear in the final output.

HPV wrote on 1/21/2003, 6:45 PM

Some people have these glitches when previewing via OHCI ext. preview. Others claim they don't. I think it comes down to system setup. I have that problem on ext. previews, but never with printing to tape.
If the problem is there after going to tape, it sounds like a reversed field order on the event. I've had Vegas 2 flip field order of events on its own.

Craig H.

jetdv wrote on 1/22/2003, 8:11 AM

Another possibility is that the opacity slider for the tracks that are jerky are not at 100%. Make sure all the sliders on video tracks are on 100% (even 99.9 will cause it to be jerky!)

dmcmeans wrote on 1/26/2003, 10:24 PM

Thanks for all the answers. Intersting bit about the opacity!

SOLUTION
Turned out the problem was not field order, like I would have suspected after reading this forum, firewire, unrendered video or the opacity slider.

It was the Pan and Crop setting on the event.

I had moved some of the events up or down (no resizing) in the Pan and Crop settings. The events that played strobish had a Center Y coordinate at a multiple of 5, like 285.

With snapping on, grid density of 16, if you pan the frame down the Y coordinate starts at 240 and goes to 270, 300, etc. At these positions, you do not get a strobing.

If you change the grid density to 64 and pan down, the Y coordinate goes to 255, 270, 285, etc.

If I panned to 285 or 255 or any position not a multiple of 10 I got the strobing behavior. When I repositioned these clips back to a multiple of 10, the strobing behavior went away.

I seem to recall seeing this behavior even in Video Factory and I always assumed I had a bad capture. I was able to verify this behavior in Vegas 4.0 Beta, too.

Is this a bug, or simply the way Sonic Foundry's video panning works?

Obviously you can get around it (once you figure it out), but if you can't really pan by 5's, then the interface shouldn't let you do it.

Thoughts?

David