Effects and Render Problem

xjerx wrote on 1/16/2006, 6:29 AM

I'm having a problem with effects not rendering right. For example....I had an image overlayed on another image. The top image had a cookie cutter with plenty of feather on it. Looks great when I play it on the timeline...however...when I render ..the effect is there for a few seconds then only the feather disappears and i'm left with these ugly hard lines on the cookie cut. Why is it doing this??? The only way I have been able to get around it for the time being is to render small 10 second sections at a time..then render all those together.

Thanks,
Jeremiah

Comments

johnmeyer wrote on 1/16/2006, 8:59 AM

Try doing a pre-render on the timeline at the point where you are doing the effect and see if it previews correctly. My guess is that the preview simply couldn't keep up at the point where your effect went "bad," and therefore you didn't see the problem.

Most likely problem is that you are using a transition or fade to black on an upper track, and it is letting video that has not been modified by the fX "show through." You can also put the cursor at the point where you know (from the rendered version) that the video is ugly, put the Preview quality to Best, wait a few seconds, and see what shows up.

You should also look at the keyframes for each fX. One of the issues in Vegas is that if you have a keyframe as the LAST keyframe in an event, and then you lengthen that event, that keyframe stays at the same time location, rather than as the last keyframe in the event. This can cause exactly the kind of problem you describe. I encountered this so often that I created a script to flag all events that have more than one keyframe, but do NOT have a keyframe on the final frame of the event. After I used this script for a few weeks I realized that, for me, I NEVER would have an event with multiple keyframes that didn't have a keyframe on the final frame and therefore modified the script to move the final keyframe to the end of the event.

Anyway, that's what I'd look for.

xjerx wrote on 1/16/2006, 12:29 PM

Neither of those things seem to be the problem...my preview runs at about 20 - 25 fps. No problems with keyframes. The only problem comes when I render. Looks fine on the timeline.

Any more suggestions?

Thanks
Jeremiah

johnmeyer wrote on 1/16/2006, 4:04 PM

I don't have any other ideas. Maybe someone else will chime in.

Billae wrote on 1/16/2006, 5:15 PM

Double check those keyframes. Look at the last keyframe on the cookie cutter effect and see if it's resetting the feathering effect. I had these sort of problems before and it was always due to that extra keyframe I accidently added. Good luck!

xjerx wrote on 1/17/2006, 9:29 AM

I checked...it's not any keyframes....because like i said....it looks like it should during preview...at 29.97 fps....the problem shows up on the rendered file. And the problem only shows up about 10 seconds into the video...no matter where I start the render.

Jeremiah