Color Management - Adobe AFTER EFFECTS CS3 PROFESSIONAL User Manual

The gamma value for an entire system—from capture, through production, to display in the viewing environment—
is the product of the gamma values used for each of the phases in the system. This product is not always 1.0, as it
would be if the operations performed for encoding exactly matched (inverted) the operations performed for
decoding. One reason for a system gamma other than 1.0 is that there is often a difference between the lighting
conditions in which a scene is captured and the lighting conditions in which it is viewed. (Consider that you usually
watch a movie in a dim environment, but the scenes aren't normally shot in a dim environment.)
For example, the device gamma for an HD camera is approximately 1/1.9, and the device gamma for an HD display
is approximately 2.2. Multiplying these values gives a system gamma of approximately 1.15, which is appropriate for
the somewhat dim television viewing conditions of a typical living room. The system gamma for motion picture
production is much higher (approximately 1.5–2.5) to accommodate the darker viewing environment of a movie
theater. The gamma for the film negative is approximately 1/1.7, and the gamma for the projection film is approxi-
mately 3–4.
After Effects 7.0 and earlier used QuickTime codecs to decode several kinds of media, and the gamma adjustments
performed on Windows were different from the gamma adjustments performed on Mac OS. The gamma adjust-
ments performed by After Effects CS3 differ from the gamma adjustments performed by these QuickTime codecs.
Gamma adjustments performed by After Effects CS3 on Windows are the same as gamma adjustments performed
by After Effects CS3 on Mac OS. Also, by not using QuickTime codecs, After Effects preserves overbrights in 32-bpc
projects. To avoid color shifts when working with projects created in After Effects 7.0 or earlier, or to match the colors
in a project created in After Effects 7.0 or earlier, select Match Legacy After Effects QuickTime Gamma Adjustments
in the Project Settings dialog box. This option is selected by default for projects created in After Effects 7.0 or earlier.
You should create new projects without this option selected.
Note: On Mac OS running on a PowerPC processor, QuickTime codecs are used for some formats (including DV, 2vuy,
and v210), whether or not you select Match Legacy After Effects QuickTime Gamma Adjustments. However, selecting
this option does modify the gamma adjustments used so that they match the behavior of After Effects 7.0 and earlier.
See also
"Linearize working space and enable linear blending" on page 244

Color management

Why you should use color management
To see a video tutorial on color management in After Effects, go to the Adobe website at
www.adobe.com/go/vid0260.
For step-by-step instructions on using color management to create movies for Flash, HDTV, motion-picture film,
and other common media, go to the Adobe website at www.adobe.com/go/learn_ae_colormanagementpaper.
Color management provides many benefits, including the following:
• The colors in imported images appear as the creators of the images intended.
• You have more control over how colors are blended within your project, for everything from motion blur to anti-
aliasing.
• The movies that you create will look as you intend when viewed on devices other than your computer monitor.
AFTER EFFECTS CS3 240
User Guide