Camera Match help

Hi all,

I'm trying to get my head around camera tracking (specifically to do a sky replacement)

I have tracked the footage with the camera tracker, added an imageplane and new bg sky and aligned them in the viewport/camera to create a 3d scene.

However, when the camera animates over the timeline, the new imageplane sky just stays where it is in 3d space - it doesnt move with the camera.

I've also tried importing the camera directly from 3dsmax, but that does the same, the new sky stays put.

I'm probably missing something simple, so any help is appreciated on this.

Attached how the flow looks.

Thanks.

The image plane should not move as the camera is doing the moving, think of it as the real world where the camera moves and the sky stays still. I would add a 3D render node that merges the new sky over the original footage (same size) and then use the alpha generated from the house as a mask. Dont forget to turn on motion blur in the Render node.