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650 Chapter 12: Animation
pixel in the current window or the subpixel
increment selected. So, if you’re zoomed out
two times and the subpixel increment is 1/16
of a pixel, the nudge increment is four image
pixels, d ue to the zoom. However, if you’re
zoomed in five times, the nudge increment is
1/16 of an image pixel, due to the subpixel level.
• Bounds: You adjust the bounding boxe s by
pressing and drag ging t he handles of the box
youwanttoadjustintheselectedgizmo.
Dragging the handles of the inner feature
bounds box adjusts the opposite corner
symmetr ically to keep the gizmo center fixed.
Typically when setting up tracker gizmos you
should create and position them all roughly in a
zoomed-outview,thenzoominononeofthem,
fine-tune its position and bounds, then tab to the
next gizmo and repeat.
Movie Window Keyboard Shortcuts
You can use the following keyboard shortcuts in
the Movie window:
• I, i: Zoomsinonaselectedgizmo.
• O,o: Zooms out on a selected gizmo.
• R, r: Resets zoom level to 100 p e rcent.
• TAB : Selects next numbered gizmo, cycles back
to first gizmo after the last.
• Dig it: Selects the numbered gizmo, only works
for gizmos 1 to 10 (0=10).
• Ar row Keys: Nudges the gizmo in the direction
of the arrow.
Cam era Tracker: Mo tion Tracke rs
Rollout
Utilities panel > Utilities rollout > More button > Util ities
dialog > Cam era Tracker > Motion Trackers rollout
TheCameraTrackerutility’sMotionTrackers
rollout sets up and controls the image feature
trackers. All the trackers created are listed here:
showing enable check mark, t r acker number,
associated scene p oint object name, and active
frame r ange. To select a tracker, click in the list.
Pro vides controls for subpixel tracking as well.
Interfa ce
On—Whenturnedon,thefeaturewillbetracked
in the image when the movie is stepped through
in the Movie Stepper, or when a full track is
performed. An X appears in the tr acker list when
turned on.
Off—When turned off, the tracker will sit at the
closest known position prior to the current frame.
Because feature tracking is computationally
intensive,sometimesit’susefultodisablethe
trackers you’re not working on to speed up movie
stepping.
All—Enables a ll the trackers.
None—Disables al l the trackers.