[Glenn Dawick]

OK right, I’m understanding this now, and feeling slightly dumb for not being able to work this out earlier.

[Glenn Dawick]

Ahhh ok, so even though the footage is bouncing around in 3D space, the Z depth pass helps place the particles in front and behind? I shall give this a try. Thank you!

[Glenn Dawick]

Hi Richard, thanks for your reply

Houdini is a 3D VFX application: https://www.sidefx.com/

I understand what your saying about imported cameras coming in at strange positions. I’ve done a few different exports from Houdini with different settings, and as you suggested with a null at 0,0,0 and all seems to be working well there.

I have parented my footage to the 3D camera as per your suggestion, but was hoping for an easier way to move the footage back and forth in 3D space without the footage resizing in screen space. For now I have just zoomed in really far and manually scaled the footage until it just touches the very edge of my composition. This method doesn’t seem very accurate.

The biggest problem when parenting the footage to the camera is because it’s parented to the camera, the footage moves around with the camera. So now the footage is not sitting at the same depth in the scene as my original 3D object was (static object with moving camera) – Is this something that I just need to manually push back and forth in depth at the same time trying to scale the footage to stay the correct size in my composition?

I’ve built a very simple example of my scene to help show what is going on. This is inside Houdini:
https://gfycat.com/dishonestinfamousamericanwigeon

Another showing inside After Effects:
https://gfycat.com/indolentreflectingamericangoldfinch

So the issue here is that the footage doesn’t stay in place, where the original 3D objects were. If I had a null sitting at the center point of the 3D objects, is there a way to reference that depth in scene from my 3D camera and tell the footage to aim toward my camera (like the script you mentioned), but also scale up / down to stay matched to the edges of my composition? This all feels very confusing!