Camera Tracking - Nuke 101: Professional Compositing and Visual Effects - page 431

You can see how the point cloud in the 3D Viewer jumped so it's flat against the
bottom of the window and aligned with the grid scene in the 3D Viewer.
YoujusttoldNukethisrepresentsthegroundplane'sZaxis.Nowdothesamefor
the X axis.
9. Again in the 2D Viewer, select two points, this time going across the screen from
left toright.Makethem asfarapart fromeach otherasyoucantoeliminate small
rotation errorandmake surethey're apart ofthe main point cloud area represent-
ing the table ( FIGURE 10.23 ) .
Figure 10.23. Selecting points for the X axis.