Apple Final Cut Pro 6 - Manual (Page 1745)

262 Part III Output
In this mode, the video track is cropped to the Clean aperture mode and scaled
according to the track’s pixel aspect ratio. For example, a 4:3 DV NTSC track appears as
640 x 480; a 16:9 DV NTSC track appears as 853 x 480.
Production Aperture Mode
Content may appear differently than in QuickTime 7. The video track is not cropped to
the Clean aperture mode, but it is scaled according to the pixel aspect ratio. Use
this option when you want to see all the pixels in your video, including the edges.
A 4:3 DV NTSC track appears as 654 x 480; a 16:9 DV NTSC track appears as 873 x 480.
Compare this to the Clean aperture mode, which crops the edge-encoding pixels on
the left and right.
Clean: pixel aspect ratio
correction applied and
edges cropped
Production: pixel aspect
ratio correction applied
with no edge cropping