Adobe After Effects CS3 - Manual (Page 592)

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Chapter 17: Rendering and exporting
Basics of rendering and exporting
About rendering and exporting
Rendering is the creation of the finished frames of a movie from a composition. The rendering of a frame is the
creation of a composited two-dimensional image from all of the layers, settings, and other information in a compo-
sition that make up the model for that image. The rendering of a movie is the frame-by-frame rendering of each of
the frames that make up the movie. For more information on how each frame is rendered, see “Render order and
collapsing transformations” on page 115.
After a composition is rendered for final output, it is processed by one or more output modules that encode the
rendered frames into one or more output files.
A movie can be made into a single output file (such as a Flash Video movie) that contains all of the rendered frames,
or it can be made into a sequence of still images (as you would do when creating output for a film recorder).
Though it is common to speak of rendering as if this term only applies to final output, the processes of creating
previews to show in the Footage, Layer, and Composition panels are also kinds of rendering. In fact, it is possible to
save a RAM preview as a movie and use that as your final output. (See “Preview video and audio” on page 120.)
Note: Some kinds of exporting don’t involve rendering and are for intermediate stages in a workflow, not for final output.
For example, you can export a project as an Adobe Premiere Pro project by choosing File > Export > Adobe Premiere
Pro Project. The project information is saved without rendering.
To see a video tutorial on rendering and exporting, visit the Adobe website at www.adobe.com/go/vid0262 .
After Effects provides a variety of formats and compression options for output. Which format and compression
options you choose depends on how your output will be used. For example, if the movie that you render from After
Effects is the final product that will be played directly to an audience, then you need to consider the medium from
which you’ll play the movie and what limitations you have on file size and data rate. By contrast, if the movie that
you create from After Effects is an intermediate product that will be used as input to a video editing system, then you
should output without compression to a format compatible with the video editing system.
Aharon Rabinowitz has an article on the Creative COW website about planning your project and deciding what
formats and settings to use for final output:
www.adobe.com/go/learn_ae_aharonplanning .
Keep in mind the fact that you can use different encoding and compression schemes for different phases of your
workflow. For example, you may choose to export a small number of frames as full-resolution still images (e.g., TIFF
files) when you need approval from a customer about the colors in a shot; whereas you may export the movie using
a lossy encoding scheme (e.g., H.264) when you need approval for the timing of the animation.
Important: You do not need to render a movie multiple times to export it to multiple formats with the same render
settings. You can export multiple versions of the same rendered movie by adding output modules to a render item in the
Render Queue panel.