Blackmagic Forum

Hi guys, I'm trying to change the view(background) throught the windows from the scene.I masked and tracked the windows(with mocha). I did a 3dtrack with PFTRACK and i exported to the 3d camera. My problem is I don't understand how I should link the 3d shapes so they follow the movement of the camera and the perspective with the movement is the correct one.

Right now what I have is that the main clip is moving(the clip recorded using steadicam) but the background is still so the effect looks like parallax effect.

I'm fairly new to fusion, I checked documentation and tools help but i didnt find place where they explain how to do in this situation.

Thanks in advance

you can put your new background in 3d space using the point cloud from your 3d track as visual helpers where things are in your scene, connect the tracked (and exported) camera and the background with a merge3d, render it with a render3d node, merge (2d merge) that under your masked footage

Your tracking should generate a 3d camera which will move, the object should be stationary in the 3d environment, you will need the 3d render node to render the object for it to be visible, then comp it over the footage.

Thanks for the replys I will try what you say, It's really close of what I was doing so probably there is some detail I'm missing.

I made some advancement, the problem is with the export from pftrack. I used maya ASCII .ma but not sure why the tracking info is not working properly(the path is not appearing), I tried the AE .ma that one shows the path but for some reason after...40 frames my original clip disapear(connected to the 3d renderer via 2d merge).

I also masked the track in pftrack since I understood that tracking all the scene makes the background move 1:1 with the image so I masked the windows to track the movement there, and the result is a more subtle movement of the background( at least the 40 frames I can get done till the foreground main clip dissapear.