User Manual

Table Of Contents
Planar Tracker Node [PTRA]
The Planar Tracker node
Planar Tracker Node Introduction
The Planar Tracker node is designed to solve a match-moving problem that commonly comes
up during post-production. As an example, live-action footage can often contain a planar
surface such as a license plate or a road sign that needs new numbers in the license plate or a
new city’s name on the road sign. Often, the problem is that the camera is moving in the shot,
so the license plate or road sign is continuously changing perspective. You cannot just merge a
new license plate over the existing one without accounting for the perspective distortions. A
time-intensive way to solve this problem would be to use a Corner Pin node and manually
keyframe the four corners. The Planar Tracker automates this keyframing process and tracks
the perspective distortions of a planar surface over time. That tracking data is then applied with
those same perspective distortions to a different foreground.
For more information on using the Planar Tracker, see Chapter 16, “Planar Tracking” in the
Fusion Studio Reference Manual or Chapter 66 in the DaVinci Resolve Reference Manual.
TIP: Part of using a Planar Tracker is also knowing when to give up and fall back to
using Fusion’s Tracker node or to manual keyframing. Some shots are simply not
trackable, or the resulting track suffers from too much jitter or drift. The Planar Tracker
is a useful time-saving node in the artist’s toolbox, but while it may track most shots, it
is not a 100% solution.
What the Planar Tracker Saves
While the Planar Tracker does save the resulting final track in the composition on disk, it does
not save temporary tracking information such as the individual point trackers (compared with
the Camera Tracker, which does save the individual point trackers). Some consequences of
this include:
The point trackers no longer appear in the viewer when a comp containing a Planar
Tracker node is saved and reloaded.
Tracking may not be resumed after a comp containing a Planar Tracker node has
been saved and reloaded. In particular, this also applies to auto saves. For this
reason, it is good to complete all planar tracking within one session.
The size of composition files is kept reasonable (in some situations, a Planar Tracker
can produce hundreds of megabytes of temporary tracking data).
Saving and loading of compositions is faster and more interactive.
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