Adobe 12040118 - After Effects Standard, Руководство

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Project settings
Project settings fall into three basic categories: how time is displayed in the project, how color data is treated in the project, and what sampling rate
to use for audio. Of these settings, the color settings are the ones that you need to think about before you do much work in your project, because
they determine how color data is interpreted as you import footage files, how color calculations are performed as you work, and how color data is
converted for final output. See Color management and Timecode and time display units.
If you enable color management for your project, the colors that you see are the same colors that your audience will see when they view the
movie that you create.
Note: Click the color depth indicator at the bottom of the Project panel to open the Project Settings dialog box. Alt-click (Windows) or Option-click
(Mac OS) to cycle through color bit depths: 8 bpc, 16 bpc, and 32 bpc. See Color depth and high dynamic range color.
Composition settings
After you prepare and import footage items, you use these footage items to create layers in a composition, where you animate and apply effects.
When you create a composition, specify composition settings such as resolution, frame size, and pixel aspect ratio for your final rendered output.
Although you can change composition settings at any time, it’s best to set them correctly as you create each new composition to avoid unexpected
results in your final rendered output. For example, the composition frame size should be the image size in the playback medium. See Composition
settings.
If you’ll be rendering and exporting a composition to more than one media format, always match the pixel dimensions for your composition to
the largest pixel dimensions used for your output. Later, you can use output modules in the Render Queue panel to encode and export a
separate version of the composition for each format. See Output modules and output module settings.
Performance, memory, and storage considerations
If you work with large compositions, make sure that you configure After Effects and your computer to maximize performance. Complex
compositions can require a large amount of memory to render, and the rendered movies can take a large amount of disk space to store. Before
you attempt to render a three-hour movie, make sure that you have the disk space available to store it. See Storage requirements for output files.
If your source footage files are on a slow disk drive (or across a slow network connection), then performance will be poor. When possible, keep
the source footage files for your project on a fast local disk drive. Ideally, you’ll have three drives: one for source footage files, one from which the
application runs, and one for rendered output.
For more information, see Improve performance and Memory & Multiprocessing preferences.
Planning for playback on computer monitors and mobile devices
When you create a movie for playback on a personal computer—whether downloaded from the Web or played from a CD-ROM—specify
composition settings, render settings, and output module settings that keep file size low. Consider that a movie with a high data rate may not play
well from an older CD-ROM drive that cannot read data from the disc fast enough. Similarly, a large movie may take a long time to download over
a dial-up network connection.
When rendering your final movie, choose a file type and encoder appropriate for the final media. The corresponding decoder must be available on
the system used by your intended audience; otherwise they will not be able to play the movie. Common codecs (encoders/decoders) include the
codecs installed with media players such as Flash Player, Windows Media Player, and QuickTime Player.
Aharon Rabinowitz provides an article on the Creative COW website about planning your project with the final delivery specifications in mind.
Trish and Chris Meyer provide an article on the Artbeats website that describes some of the considerations for creating video for the Web.
For more information about encoding and compression options for After Effects, see this FAQ entry: “FAQ: What is the best format for rendering
and exporting from After Effects?”
Mobile devices
Many of the considerations for creating movies for playback on mobile devices, such as mobile phones and the Apple iPod, are similar to the
considerations for creating movies for playback on personal computers—but the limitations are even more extreme. Because the amount of
storage (disk space) and processor power are less for mobile phones than for personal computers, file size and data rate for movies must be even
more tightly controlled.
Screen dimensions, video frame rates, and color gamuts vary greatly from one mobile device to another. Adobe Device Central contains device
profiles that provide information about these characteristics. You can create a set of After Effects compositions tailored for a selected set of
devices by using the File > New Document In > After Effects command in Adobe Device Central. (See Create compositions for playback on mobile
devices.)
Use these tips when shooting video for mobile devices:
Tight shots are better. It’s hard to see a face on a tiny screen unless it’s shot in relative close-up.
Light your subjects well, and keep them separated from the background; the colors and brightness values between background and subject
should not be too similar.
Avoid excessive zooming and rolling, which hinder temporal compression schemes.