GRASS VALLEY zodiak, User Manual

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78 Zodiak User Manual
Section 2 — Concepts
Perspective
— Changing the viewer’s apparent viewpoint of a picture. This
only applies when a picture is tilted so part of it is farther from the viewer.
The farther portion appears smaller than the closer portion, and the
amount of perspective controls how much smaller the distant part is
(
Figure 48 ). Multi-channel perspective is discussed later in this section.
Axis Location
The axis location of the channel determines the center point of translations,
spins, and rotations for that channel. You can move the axis to a new loca-
tion to change the behavior of that channel. The axis location can be within
or outside the screen area (
Figure 49 ).
Figure 49. Frame of Reference Axis Locations
Source and Target Space
The Zodiak Transform Engine uses source and target space frames of refer-
ence.
• Source space for a control channel uses that channel’s coordinate
system for reference.
• Target space for a channel uses the next higher level’s coordinate
system for reference.
Being able to use both source and target space can help make effects editing
easier. One frame of reference may offer a simple and easy to understand
context for a picture transform, while in another frame of reference the
same transform may be difficult to understand and control. Zodiak Trans-
form Engine effects can also employ both source and target space directed
transforms simultaneously, which can create complex and beautiful effects.
The simplest example for source and target space concerns a channel that
has been rotated while the global channel remains unchanged (
Figure 50 ).
Axis At
Center of Picture
Axis Off
Center of Picture
Axis Off Screen
Y
Z
X
Y
Z
X
X
Y
Z
Z Axis Rotation at Different Axis Locations
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