027: Aspect ratio refresher (or why some movies are still "letterboxed" on your widescreen TV).
The vast majority of modern movies are filmed in one of two aspect ratios: 1.85:1 (also called "flat") or 2.39:1 (also called "CinemaScope" or simply "'Scope").
"Aspect ratio" refers to the relationship between the width and height of the movie image. An image filmed flat is 1.85 times wider than it is tall, and a 'Scope image is 2.39 times wider than it is tall.
A couple of examples...
Movies filmed in the 1.85:1 format include Juno, Pan's Labyrinth, and Eastern Promises (pictured).
Interplanetary and Hide and Creep are also 1.85:1 movies.
Movies filmed in the 2.39:1 format include No Country For Old Men, There Will Be Blood, and Jaws (pictured).
1.85:1 images are a good fit for high definition television. The HDTV aspect ratio of 1.78:1 is very close to 1.85:1, so any cropping or letterboxing of the movie image for video presentation is negligable, if even noticable.
2.39:1 images, however, are another story. Cropping them to 1.78:1 loses about 25% of the original content.
So, to keep the compositions as the filmmakers intended, some letterboxing is necessary. Even on so-called widescreen TVs.