> So you're saying to modify just one frame, I have to create a span of one frame?
Yes. But if you're trying to only affect one frame, something odd is going on. Is there a flash of light or other aspect of the image that only appears for one frame? The whole point of Roto Brush is that corrections that you make on one frame are supposed to inform the effect about how to make decisions about the same image regions on the subsequent frames.
> Is there any way to "break" a span into two parts?
No. You'd have to trim a span back and then create a new one outside of it. If you think that being able to split a span would be useful, please
file a feature request.
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Todd Kopriva, Adobe Systems Incorporated
Technical Support for professional video software
After Effects Help & Support
Premiere Pro Help & Support
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