Size, Rotation, Spin – Grass Valley Kayak HD v.6.9.3 User Manual
Page 74: Skew, Aspect, Perspective

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Kayak — User Manual
Section 2 — Concepts
For perspective calculations the factory default viewpoint places the
viewer -16.67 screen units from the monitor screen surface (4 x 3 aspect
ratio). In this case, moving a full screen image 16.67 screen units back
behind the screen makes the picture appear half its normal size to the
viewer.
Size
Picture size is defined relative to picture screen units. A size of 0.50 indi-
cates a picture is one-half its full size in linear edge measures. It is one
quarter of its full size area.
Rotation
Rotation is measured fractionally with respect to 360°. A value of 0.25 indi-
cates a rotation of 90 degrees; 0.50 indicates 180 degrees (maximum rota-
tion).
Rotation values can be positive or negative, which determines the direction
of rotation.
Spin
Spins are measured in number of 360° rotations (up to 999). Fractional spin
values are also supported. A single axis 0.50 spin is the same as a single axis
0.50 rotation. Spin values can be positive or negative, which determines the
direction of spin.
Skew
Skew supports values of ±999, though extreme values will probably rarely
be used.
Aspect
Aspect values are in percentage of the original size, with 1.0 = 100%, 0.5 =
50%, etc.
Perspective
Perspective supports values from 0-100, with 0.06 as the default in 4x3
operation and 0.015 in 16x9.