Hey Dave, usually people tell me TLDR so I'm always trying to make it as short as possible! But thanks for being willing to help; I'll add some more info.
Some pertinent details: I'm using AE CC 2015.3, Windows 7, am working with 1920x1080 footage, and haven't figured this out/ I've never had it working before.
The goal is to add motion (pan left/right through scaling up a bit then adding position keyframes, zoom in/out by slowly scaling up or scaling it up and then slowly scaling it down) to almost every cut/angle of my Premiere multicam sequence. I'm thinking the way to accomplish that might be through flattening/export to AE, because Premiere has limited motion functionality. When I flatten/export my multicam sequence to AE, the angles all come in as different layers which is super cool!
I'm trying to do this in the most efficient way possible, while ideally in a way that is editable/adjustable after the fact if I want to change the rate of motion. I've parented layers to nulls before, but it doesn't seem like that would do what I need.
For example: If I add a zoom in on "Clip A" (scaling up from 100% to 120%) starting with a keyframe at the 5th second of the composition and have the 120% keyframe at the 30th second of comp, when I parent "Clip Z" (that's 20 minutes later in the composition), to that same null, it's telling Clip Z to zoom from 100% to 120% far before clip Z even became visible. I'm trying to find a way to be able to make Clip A and Clip Z (and a lot of other randomly selected clips) to scale from 100% at their respective in points to 120% at their respective out points in a way that isn't adding/copying/pasting keyframes to each clip individually (because it takes forever and more importantly means I have to go back and edit literally 100-150 keyframes for a simple change in scale).
Thank you for any help you may offer, and I'd be happy to add any more details you'd like! This has been stumping me lately and I'm really trying to figure it out and hitting a wall.
Ugh. No automated way to do that stuff! The best I can offer is to duplicate nulls, remove any parenting to the nulls, find the candidate clips, then parent to the duplicated mulls. VERY messy.
Why can't you just do this in PP? It might be easier there.
The goal is to add motion (pan left/right through scaling up a bit then adding position keyframes, zoom in/out by slowly scaling up or scaling it up and then slowly scaling it down) to almost every cut/angle of my Premiere multicam sequence.
I'm trying to find a way to be able to make Clip A and Clip Z (and a lot of other randomly selected clips) to scale from 100% at their respective in points to 120% at their respective out points
This is something an expression might do for you. you can access the in and out point of the layer. using slider expression controls you could set the max scale for example. same goes for position. what you are looking for is to type a setting for speed and direction and let Ae roll with it. this is similar to what an App like Motion does. I do believe the in to out is less important. imagine a 3 second footage that scales from 100% to 120%and the same preset for a 10 second footage... fast...slow... doesn't look so good. you would probably prefer to have the same speed for both of them in no relation to the out point. or set different speeds. it will just move at a certain speed until the layer is trimmed, same with scale, but the in and out is not helping here I think.
For Position: this is where "Drift Over Time" preset comes in handy (Effects & Presets - type " drift over time"). it gives you the same speed no matter what length of layer and direction and... no keyframes you will have controls for both as effects on the footage layer.
For Scale: you can do the same thing with scale by simple expression to the scale transform (of the layer, not the Drift Over Time preset) like this:
veloc = effect("Scale Speed")("Slider"); //horizontal velocity (pixels per second)
x = scale + (time - inPoint) *veloc;
y = scale + (time - inPoint) *veloc;
now I can control the speed for scale and position and direction for any layer. bare in mind, this is hardly an elegant setup. I don't know too much about expressions and you can guarantee there are MUCH more elegant ways of doing this, but it works.
One note of caution. AE is lousy at long projects. If it were me, and I do this all the time, I shoot 4K then put my shots in a 2K Premiere Pro timeline and then just adjust the position and scale in Premiere Pro to improve the framing. IF there is a specific shot that needs some camera movement it's pretty easy to do in Premiere and you can ease the keyframes which is what you can do in AE. The easing is exactly the same. Setting the keyframes is just the same. You can even expose the layer handles in Premiere Pro and drag things around in the frame. You can even do Mask Tracking in Premiere Pro.
The only thing you don't get in Premiere Pro is the Graph editor. Your adjustments will go much faster and your rendering time will be much faster. Moving a long movie into AE after you have rendered it so you can add simulated camera moves makes no sense at all.
IF you really need to do some sophisticated moves in AE then work on only that shot in AE and dive into the Graph Editor to fine tune the motion.