scene transitions

rlsnyder wrote on 8/11/2004, 5:51 PM
In working with Vegas 3.0 and 4.0 over the past year, I have noticed several occasional characteristics of simple cuts between scenes. I would like to better understand the origin of these characterisitics.

1) The viewed transition can sometimes appear jerky (as if the new scene were sliding into place), even though successive single frames on the timeline show a clean transition. I'm wondering if this is perhaps a psychological effect that depends on the contrast or lack of contrast between the low wave number content of the two scenes?

2) Sometimes Vegas introduces into a transition very brief audio fades on one or the other side of the transition. These fades can typically be removed manually, but it seems difficult to completely free the timeline from them. They are in any event inconsequential (because they are so short). But what has caused them? Are they the result of poor mouse technique? A mismatch between video and audio sample rates?

Comments

wolfbass wrote on 8/11/2004, 6:29 PM
Dude:

The transitons may appear jerky due to the transition taxing the system.

Try RAM rendering the transition. Use SHIFT B

Wait a moment, and Hey! Presto! It will appear smooth!

Hope this helps.

Andy
rlsnyder wrote on 8/11/2004, 6:52 PM
Regarding 1), I'm not just referring to playing the transition on the Vegas timeline, but also playing the resulting mpeg2 rendering of this transition on a set top DVD player.
wolfbass wrote on 8/11/2004, 7:03 PM
OK.

Sorry, Misunderstood. One of the more experienced users might need to chip in here.

A
stepfour wrote on 8/11/2004, 11:03 PM
Try nudging one or both of the events. Also make sure you don't have too much, or too little overlap for the transition you are using. If you've done any slicing and dicing right in that area, you could also have a difficult to detect gap on one of the events. I have found that transitions in areas where there has been a split can be bad news. Worst case scenario is you have one or more of the mysterious phantom frames that have been discussed in numerous threads in this forum.
rlsnyder wrote on 8/12/2004, 8:37 AM
Searching on 'phantom frames' led me to a previous post that outlined some keystokes for navigating the timeline that I was not familiar with. I now see that when introduced to the timeline, raw clips typically have video and audio tracks that are of slightly different lengths (presumably because the sample rates are incommensurate). Therefore, if one wants a totally clean transition from one scene to the next, it would appear necessary, as a standard practice, to trim at least one video frame from the end of each clip. Whether the fact that I have not been doing this accounts for the jerkiness I report in point 1), I do not yet know.

Coincidentally, I think I have discovered the cause of the brief audio fades reported in point 2). The 'Quickfade Audio Edits' Option is apparently on by default. Turning this off eliminates the fades.

I have also discovered the 'Quantize to Frame' Option, which I have not previously used. I'm thinking that if the timeline is quantized to video frames, there should be minimum opportunity for glitches at the scene transitions.

Thanks to all for your comments.