Adobe After Effects CS3 - Manual (Page 130)

AFTER EFFECTS CS3
User Guide
125
• Adaptive Resolution Decreases the preview resolution of layers when necessary to maintain speed of updating of
images during editing and other interactions. The Adaptive Resolution Limit value in the Fast Previews area in the
Previews preferences category specifies the maximum reduction in resolution to use.
• OpenGL-Interactive or OpenGL-Always On OpenGL mode provides high-quality previews that require less
rendering time than other playback modes. OpenGL can also be used to speed up rendering to final output. OpenGL
features in After Effects rely on OpenGL features of your video hardware. When OpenGL does not support a feature,
it simply creates a preview without using that feature. For example, if your layers contain shadows and your OpenGL
hardware does not support shadows, the preview will not contain shadows. Select OpenGL-Interactive to use
OpenGL only for interactions, such as manually previewing (scrubbing) in the Timeline panel or dragging a layer in
the Composition panel. You can tell that OpenGL is engaging by looking at the Fast Previews icon, which will light
up. Select OpenGL-Always On to use OpenGL for all previews. In this mode, “OpenGL” will appear in the upper-
left corner of each view in the Composition panel.
Note: The Enable OpenGL option in the Fast Previews area of the Preview preferences category must be selected for you
to use OpenGL.
To prevent After Effects from updating images in the Footage, Layer, or Composition panels, press the Caps Lock key.
When you make a change that would otherwise appear in a panel, After Effects adds a red bar at the bottom of the
panel with a text reminder that image refresh is disabled. After Effects continues to update panel controls such as motion
paths, anchor points, and mask outlines as you move them. To resume panel updates and display all changes, press Caps
Lock again. Pressing Caps Lock is a good way to prevent views from being refreshed for each frame during rendering for
final output.
See also
“Render with OpenGL” on page 593
Work with snapshots
When you want to compare one view to another in the Composition, Layer, or Footage panel, take a snapshot. For
example, you might want to compare two frames at different times in a movie.
Snapshots taken in one kind of panel can be displayed in another kind. For example, you can take a snapshot of a
Layer panel and display the snapshot in the Composition or Footage panel. Displaying a snapshot does not replace
the content of the panel. If the snapshot has a different size or aspect ratio than the panel in which you display it, the
snapshot is resized to fit the current view.
Snapshots are for reference only and do not become part of the layer, composition, or rendered movie.
A sound is generated when you take a snapshot.
• To take a snapshot, click the Take Snapshot button at the bottom of the panel or press Shift+F5, Shift+F6,
Shift+F7, or Shift+F8.
• To view the most recent snapshot, click and hold the Show Last Snapshot button at the bottom of the panel.
• To view a specific snapshot, press and hold F5, F6, F7, or F8.
• To purge a snapshot, hold down Ctrl+Shift (Windows) or Command+Shift (Mac OS) and press F5, F6, F7, or F8.
• To free all memory used to store snapshots, choose Edit > Purge > Snapshot.