Pre-compose (select, Ctrl+Shift+C), then time-stretch the resulting comp layer.
You could precompose them and time stretch the precomp.
a little awkward, but it works. thanks!
I've a similar question but the solution above doesn't seem to work for me. Im in AE CS5 and I've a comp of 5s with five or six layers, each containing various effects. I want to extend that to 7s. I followed the control/shift/c solution and tried all variables of time stretching but even stetching each layer the animation stops at the original 5s limit. Any hints where I'm going wrong?
You're precomposing all the layers you want to time stretch but you have to make the main composition longer too.
Any hints where I'm going wrong?
Here's my guess: when you precompose the layers, you're not making the main comp 7 seconds long. Or perhaps you're not enabling Time Remapping for the layer, and dragging that keyframe over to the end of the 7-second main comp... and don't forget to change the precomp's out point, either.