Advanced, Experimental VFX Animation and Techniques
Blog Week #3, Nuke Tracking Methods
Blog Week #3, Nuke Tracking Methods
2D Match Move, Planar Tracking, and Types of Movement
When trying to decide what sort of tracking strategy is most appropriate for the situation at hand, if the footage involves substantial camera movement, 3D tracking is necessary. Otherwise, for tracks that involve modest camera movement, e.g. parallax, then 2D tracking can be effective. For example, simple tracking of a billboard which remains moderately still through a modest degree of parallax, is readily accomplished by means of 2D match move (as further below, the following simple track of a billboard does not involve any significant change in perspective and only modest movement of the camera). To track shots with significant change in perspective, planar tracking is necessary (and, as mentioned, 3D tracking is necessary for substantial spatial or camera movement).
When trying to decide what sort of tracking strategy is most appropriate for the situation at hand, if the footage involves substantial camera movement, 3D tracking is necessary. Otherwise, for tracks that involve modest camera movement, e.g. parallax, then 2D tracking can be effective. For example, simple tracking of a billboard which remains moderately still through a modest degree of parallax, is readily accomplished by means of 2D match move (as further below, the following simple track of a billboard does not involve any significant change in perspective and only modest movement of the camera). To track shots with significant change in perspective, planar tracking is necessary (and, as mentioned, 3D tracking is necessary for substantial spatial or camera movement).
Tracking Techniques: Alternate Strategies
The first component of our 2D tracking lecture involved a review of billboard footage which included movement mainly limited to parallax. Because the billboard screen replacement is ideally managed by means of targeting the 4 corners, a corner pin track was conducted, but the following screen recording shows that a transform match move results in a track that follows the same error analysis as the original corner pin track, i.e. the transform match move approach is also reasonable for this footage.
