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If I'm taking still timelapse photos of a stationary subject while moving along an arc radiating out from the object, what should I mark to stabilize rotation?

To make the question more tangible, let's imagine a cube. In the middle of the cube there is an X which I can use for the 2D stabilization point. Now I want to stabilize rotation. But the cube's edges are going to undergo perspective distortion as I rotate around. The horizon may not be visible from some perspectives either. So there's nothing in the scene itself to track rotation, but it's obvious upon rendering the animation that there is rotational instability present.

It seems to me almost the only way to do it would be to create a 3D model that corresponds with the 2D timelapse photos and superimpose the 3D cube over the physical cube. Then each frame could be rotated to keep it's perspective consistent with the rotating 3D model. Although this seems like a possible solution, I'm not sure what workflow I would use to achieve it.

EDIT: I've been watching Track, Match, Blend and am learning more about some of the limitations. In the tutorial it was shown how panning motion can't be solved automatically. Perhaps I don't understand enough about the limitations of rotational stabilization. It seems to only work on a 2D plane. But if the camera is moving, either in a straight line or in an arc, is it possible to stabilize rotation?

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Rotational stabilisation requires 2 points/trackers that remain stationary relative to each other not the edge of frame or camera.

If that isn't available then your other solution will require a good 3d solve, from lots of trackers. But it sounds like you may not have much to track there either.

Perhaps you could use 2 planar tracks they tend to track features that cover an area instead of a point.

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  • $\begingroup$ Is there a way I could copy the positional marker track, move it down a bit, and then use it to adjust the rotation by making slight left-right adjustments? $\endgroup$ – Reed G. Law May 27 '14 at 9:49
  • $\begingroup$ Rotation only occurs between 2 points/markers but I don't think that you can offset the centre of a tracker to effect the rotation from another spot. Is there any chance you could get a 3D solve instead? Then you may be able to reconstruct the scene and fly a virtual camera instead. $\endgroup$ – 3pointedit Jun 6 '14 at 14:16
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A quick test shows that you cannot add rotational trackers. Nor can you add alternate 2D rotation tracks (pairs) from the 1 movie clip. Also you cannot load alternate versions of the same clip to add rotational tracks.

So it seems that you can hand off stabilise between multiple markers or tracks but not for rotation.

It seems that you will have to try for a 3D solve of your camera instead.

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An interesting idea would be to track one corner as a second point and then try to stabilize the second point to something like a moving average of the second track.

To put it differently: The second point obviously cannot be fixed entirely, but it should be possible to keep it on a pre-determined track. This track can either be computed by some means, or it can be constructed (maybe...) from a moving average of the actual track.

This would allow for the second tracked point to still move, albeit in a very smooth fashion.

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  • $\begingroup$ Interesting idea. Can Blender do this? $\endgroup$ – Reed G. Law Apr 24 '15 at 0:23

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