Adobe 12040118 - After Effects Standard, Руководство

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Units
Slider Minimum
(Windows) or decimal point (.) (Mac OS) on the numeric keypad.
Use standard preview to play video
Standard preview (commonly called spacebar play ) plays video in the active Composition, Layer, or Footage panel from the current time. Standard
preview does not play audio.
Standard previews play at a speed as close to the speed of real time as possible. However, for complex compositions, the speed of the preview
may be much less than real-time speed.
Click the Play button in the Preview panel, or press the spacebar.
Manually preview (scrub) video and audio
To manually preview ( scrub ) video in the Timeline panel or go to a specific frame, drag the current-time indicator.
To scrub audio in the Timeline panel, Ctrl+Alt-drag (Windows) or Option-drag (Mac OS) the current-time indicator.
To scrub audio and video in the Timeline panel, Ctrl-drag (Windows) or Command-drag (Mac OS) the current-time indicator.
If you stop moving the current-time indicator while keeping the mouse button depressed, a short section of audio loops.
To manually preview (scrub) only the frames that are already rendered and cached into the RAM cache, press the Caps Lock key before
dragging the current-time indicator. This prevents After Effects from trying to render other frames when you drag over or past them. This
technique is useful when you want to manually preview some frames that you rendered using RAM preview settings that used an option to skip
every other frame.
Audio panel options
During previews, the Audio panel volume unit (VU) meter actively displays audio volume levels. At the top of the VU meter, signals indicate when
the audio is
clipping —a distortion that occurs when the audio signal exceeds the maximum level that the audio device allows.
To view the VU meter and levels controls in more detail, increase the height of the Audio panel.
Audio panel
A. VU meter B. Level controls C. Level units D. Audio panel menu E. Level values
Choose Options in the Audio panel menu to specify the following options:
Choose whether to display audio levels in decibels or in percentages. 100% equals 0 decibels (0 dB).
The minimum audio level to display in the Audio panel.
Additional tips and options for previewing
With all previewing methods—as with rendering to final output—a layer is only visible in rendered previews if its Video layer switch is selected.
Some factors that influence the speed with which previews are rendered include layer switches, Fast Previews settings, preference settings, and
composition settings.
One of the simplest and most influential of the preview settings controls is the Resolution/Down Sample Factor setting menu at the bottom of the
Composition panel. Choose a value other than Full from this menu to see all previews at a lower resolution. (See
Resolution .)
To turn pixel-aspect ratio correction on or off for previews, click the Toggle Pixel Aspect Ratio Correction button at the bottom of the panel.
The quality of the pixel aspect ratio correction is determined by the Zoom Quality preference. (See
Viewer Quality preferences .)
When possible, preview on the same kind of device that your audience will use to view your final output. For example, you can preview on an
external video monitor. To see your composition as it will appear on a mobile device—such as a mobile phone—first render your composition to
final output, and then use Adobe Device Central to view the movie.
If you create compositions for mobile devices using Device Central, you can preview the compositions within After Effects with guides and settings