Adobe After Effects CS4 - Manual (Page 611)

605 USING AFTER EFFECTS CS4
Effects and animation presets
Last updated 12/21/2009
Camera Position controls
X Rotation, Y Rotation, Z Rotation Rotate the camera around the corresponding axis. Use these controls to look at the
cards from the top, side, back, or any other angle.
X, Y Position Where the camera is positioned in x,y space.
Z Position Where the camera is positioned along the z axis. Smaller numbers move the camera closer to the cards, and
larger numbers move the camera away from the cards.
Focal Length The distance from the camera to the image. Smaller numbers zoom in.
Transform Order The order in which the camera rotates around its three axes, and whether the camera rotates before
or after it’s positioned using the other Camera Position controls.
Corner Pins controls
Corner Pinning is an alternative camera control system. Use it as an aid for compositing the result of the effect into a
scene on a flat surface that is tilted with respect to the frame.
Upper Left Corner, Upper Right Corner, Lower Left Corner, Lower Right Corner Where to attach each of the corners of
the layer.
Auto Focal Length Controls the perspective of the effect during the animation. If Auto Focal Length is unselected, the
focal length you specify is used to find a camera position and orientation that place the corners of the layer at the corner
pins, if possible. If not, the layer is replaced by its outline, drawn between the pins. If Auto Focal Length is selected, the
focal length required to match the corner points is used, if possible. If not, it interpolates the correct value from nearby
frames.
Focal Length Overrides the other settings if the results you’ve obtained aren’t what you need. If you set the Focal
Length to something that doesn’t correspond to what the focal length would be if the pins were actually in that
configuration, the image may look unusual (strangely sheared, for example). But if you know the focal length that you
are trying to match, this control is the easiest way to get correct results.
Jitter controls
Adding jitter (Position Jitter and Rotation Jitter) makes this transition more realistic. Jitter works on the cards before,
during, and after the transition occurs. If you want the jitter to happen only during the transition, start with the Jitter
Amount at 0, animate it up to the desired amount during the transition, and then animate it back down to 0 at the
completion of the transition.
Position Jitter Specifies the amount and speed of jitter at the x, y, and z axes. X, Y, and Z Jitter Amount specify the
amount of extraneous movement. The X, Y, and Z Jitter Speed values specify the speed of jitter for each Jitter Amount
option.
Rotation Jitter Specifies the amount and speed of rotation jitter around the x, y, and z axes. X, Y, and Z Rotation Jitter
Amount specify the amount of rotational jitter along an axis. A value of 90° makes it possible for a card to rotate up to
90° in either direction. The X, Y, and Z Rot Jitter Speed values specify the speed of rotational jitter.
Gradient Wipe effect
The Gradient Wipe effect causes pixels in the layer to become transparent based on the luminance values of
corresponding pixels in another layer, called the gradient layer. Dark pixels in the gradient layer cause the
corresponding pixels to become transparent at a lower Transition Completion value. For example, a simple grayscale
gradient layer that goes from black on the left to white on the right causes the underlying layer to be revealed from left
to right as Transition Completion increases.
This effect works with 8-bpc and 16-bpc color.