Adobe After Effects - Manual (Page 104)

2. Do one of the following:
Choose a composition settings preset from the Preset menu.
Choose a value from the Pixel Aspect Ratio menu.
Common pixel aspect ratios
Adobe also recommends
Camera Raw
Importing assets from tapeless formats
Importing XML project files from Final Cut Pro
Pixel aspect ratio When to use
Square pixels 1.0 Footage has a 640x480 or 648x486
frame size, is 1920x1080 HD (not
HDV or DVCPRO HD), is 1280x720
HD or HDV, or was exported from an
application that doesn’t support
nonsquare pixels. This setting can also
be appropriate for footage that was
transferred from film or for customized
projects.
D1/DV NTSC 0.91 Footage has a 720x486 or 720x480
frame size, and the desired result is a
4:3 frame aspect ratio. This setting
can also be appropriate for footage
that was exported from an application
that works with nonsquare pixels, such
as a 3D animation application.
D1/DV NTSC Widescreen 1.21 Footage has a 720x486 or 720x480
frame size, and the desired result is a
16:9 frame aspect ratio.
D1/DV PAL 1.09 Footage has a 720x576 frame size,
and the desired result is a 4:3 frame
aspect ratio.
D1/DV PAL Widescreen 1.46 Footage has a 720x576 frame size,
and the desired result is a 16:9 frame
aspect ratio.
Anamorphic 2:1 2.0 Footage was shot using an
anamorphic film lens, or it was
anamorphically transferred from a film
frame with a 2:1 aspect ratio.
HDV 1080/DVCPRO HD 720, HD
Anamorphic 1080 1.33 Footage has a 1440x1080 or 960x720
frame size, and the desired result is a
16:9 frame aspect ratio.
DVCPRO HD 1080 1.5 Footage has a 1280x1080 frame size,
and the desired result is a 16:9 frame
aspect ratio.
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