[Tomasz Kaye]

I’m posting a new answer to this old question since I just needed to figure this out and this thread came up in my search. Here’s a bearable workaround that works in AE CC and perhaps in earlier versions:

“an Insert Edit will place a new layer in the timeline and push back all layers to the end of the added layer. So, if the new layer is 2 seconds in length, all existing layers at that point will be pushed back 2 seconds. Bear in mind that if the existing layers do not end at the CTI/playhead, an insert edit will split them in two, so that the first part is before the new layer, and the second part jumps after the new layer’s duration. This happens because After Effects uses layers, rather than tracks as editing applications do. If existing layers end or begin at the the CTI, this won’t happen.

To perform an insert edit, alt-double click a footage item in the project panel, and this will open the footage panel. Pick an In and Out point (use the { and } buttons) for the footage to set duration and then press the Insert edit button (see image below). This will insert the footage item as a new layer at the current time, and push back everything to the new layer’s end.”

Source: https://forums.adobe.com/thread/514252

(Also, Dave LaRonde’s posts are routinely condescending and dismissive. I suggest readers looking for answers save valuable time by skipping over them).

[Tomasz Kaye]

That works perfectly. Thank you.

I had tried that approach earlier but for some reason the animation seemed to be running for all particles at the same moment (including for the as yet ‘unborn’ particles, which then later appeared in the fully revealed state). It could be that I was using the standard c4d emitter when I was getting that result, instead of thinking particles. I’m not sure any more though.

I also came across your example file ‘StepEffectorTime.c4d’ which seems to point to a mograph solution that may be a more elegant approach so I’ll look into that too.

Thanks again for your help!

[Tomasz Kaye]

In the channels palette select the alpha channel. Then click the ‘load selection’ button at the bottom of the palette (a dotted circle). Select the RGB channel again. You may need to invert your selection to select the background (shift+apple+i on a mac, or do it via the Select menu). Press the delete key to remove the selected background.

[Tomasz Kaye]

Yes i have mograph. Sorry, i meant to mention that–forgot to.