Apple Final Cut Pro HD (4.5): New Features - Manual (Page 113)

Appendix High Definition Video Fundamentals 113
To preserve the aspect ratio of widescreen movies on a 4 x 3 screen, widescreen movies
are scaled until the entire image fits within the 4 x 3 frame. The remaining space at the
top and bottom of the 4 x 3 frame is left empty, and is almost always made black. If a
film or video was shot to be exclusively viewed in a widescreen venue, this technique is
usually the best approach for downconversion. However, it has the disadvantage of
poorly using the vertical resolution of the 4 x 3 frame, which is already lower resolution
to start with.
Cropping
If you are careful during production to keep both aspect ratios in mind, making sure
important action stays within the 4 x 3 center of the 16 x 9 frame, you can choose to
crop your entire movie within a 4 x 3 frame (or a 14 x 9 frame, sometimes used in
Great Britain). This method allows you to fill the whole 4 x 3 screen with some portion
(usually the center) of your 16 x 9 image. This simple crop can be applied to the entire
film without significantly altering the visual storytelling.
For broadcast in the UK, 16 x 9 images are often cropped to 14 x 9 and letterboxed
within a 4 x 3 frame (for standard definition PAL televisions). Because a 14 x 9 image has
less severe letterbox (that is, smaller black bars at the top and the bottom of the frame),
some viewers find this less objectionable.
16 x 9 to 4 x 3
crop center
16 x 9 frame 4 x 3 frame
UP01022.Book Page 113 Tuesday, March 23, 2004 7:32 PM