Positioning Nodes in Blackmagic Fusion

[Curtis Mack]

I recently created what started out as a simple composite, consisting of a background clip, a foreground clip, a couple of trackers, and a polygon animated mask. The mask was rotoscoped from the top clip. When adjusting the position of the top clip and the mask, I could not find a straightforward way to keep them locked together. I had to adjust them individually, which disrupted the registration of the mask with respect to the top clip. It appears that the only way to do this is to create a background, adjust the alpha channel to zero, matte the top clip and mask to the background, and save the result to the file system. After that, you can bring in the saved file as a Loader and merge it with the bottom clip. You can then adjust the position of the Loader node. This seems like a kludge to me. Is there a simple way to lock the mask and its parent node together while adjusting their position?
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[El Director]

Underlay node might work for you. When you see videos or pictures of Fusion and they have what looks like a colored stickey note under a group of nodes, that's an Underlay, or Backdrop if you're in Nuke. It effectively serves as visual precomp or group, keeping the nodes together so you can move the entire group at once and also organize your scene.



In the above pic, it's Nuke, but it's the same thing. I've visually separated the Fire and Rainbow elements from the Background element, but if I move the Red or Orange box, the nodes move too. Hope this helps