Aspect Ratio

Five standard ratios are shown by diagonal lines: 16:9, 16:10, 3:2, 4:3, and 5:4.

We will cover the two most common, 4:3 & 16:9 below.

 

4:3 Standard
The 4:3 ratio for standard television has been in use since television's origins and many use the same aspect ratio. 4:3 is the aspect ratio defined by the Academy of Motion Picture Arts and Sciences as a standard after the advent of optical sound-on-film. By having TV match this aspect ratio, films previously photographed on film could be satisfactorily viewed on TV in the early days of the medium ( i.e. the 40's and the 50's). When cinema attendance dropped, Hollywood created widescreen aspect ratios to immerse the viewer in a more realistic experience and, possibly, to make the cinema experience more of a spectacle that could not be achieved at home on a regular TV set.

 

16:9 Standard
16:9 is the international standard format of HDTV as used in Australia, Japan, Canada, and the United States, as well as in Europe on satellite and non-HD widescreen television EDTV PAL-plus. Japan originally started with a 5:3 ratio but converted when the international standards group introduced a wider ratio of XXX to 3 (=16:9). Many digital video cameras have the capability to record in 16:9. Anamorphic DVD transfers store the information in 16:9 vertically stretched to 4:3; if the TV can handle an anamorphic image the signal will be de-anamorphosed by the TV to 16:9. If not, the DVD player will unstretch the image and add letterboxing before sending the image to the TV. Wider ratios such as 1.85:1 and 2.40:1 are accommodated within the 16:9 DVD frame by adding some additional black bars withing the image itself.