Hi there,
The simplest way is to select the clip you want to key (and the underlying clip if necessary) in the Timeline in PremPro. Right-click on these selected clips and choose “Replace with After Effects Composition”.
This will create a linked comp in AE. Do your keying and then save the AE project.
Jump back to PremPro and the timeline should be updated with your chages made in AE.
If you need to adjust the settings further do not do the same process again, simply right-click on the dynamically linked portion and choose edit Original, this will re-open the comp where you can make changes and save when finished.
Hope this helps!
cheers,
Angie
Angie Taylor animation & illustration for television, film, web and devices
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