If you are an avid Turner Classic Movies channel watcher, you may have seen the short documentary about the difference between letterbox and full screen or as the directors on the short interpreted it as "pan and scan." If you have not seen the short documentary, you may notice that films from certain decades are either shot to fit the entire screen of a television, such as "Singing in the Rain" (1952) or "Lawrence of Arabia" (1962). This is what is known as "aspect ratio" and largely contributes to the way we watch classic films.
Before 1953, all studio films were shot in Academy format, which is the aspect ratio of a frame for 35 mm film. The Academy Arts and Sciences of Motion Picture considered it the standard film aspect since 1932 when it was created in order to fit the film screens in movie palaces across the country at the time. Although the Academy format is obsolete now, it is still being used under certain artist circumstances. The most recent film to use the Academy Format was the Oscar winning modern silent film "The Artist" (2011). Director Michel Hazanavicius used the format to demonstrate the historical presence and significance of the film's story which is set during 1920s Hollywood.
Meanwhile, although widescreen and anamorphic lenses were not very popular for the first 50 years of film, it was used experimentally until the 1930s. It was highly utilized in filming News Reels and select films such as "Danger Lights" (1930). But the Great Depression forced studios to find a cheaper way, which was the Academy format.
With the innovation of television, the studio heads were nervous about losing business to the new technology. Therefore in 1953, CinemaScope and the like were created and bought by 20th Century Fox. If you see vintage movie trailers or posters that advertise the phrase "In CinemaScope" it was a way of trying to attracting people to the movie theaters. CinemaScope and subsequent widescreen formatting forever changed the way directors created film and the way we watch them.
Later, when television was open to broadcasting films into people's homes, it has since been an ongoing debate whether or not it is better to watch a film in "letterbox" or in "full screen." Letterbox is the preferred aspect ratio for most, if not all, film directors. It is called "letterbox" because it looks like the slot of a mail box. It preserves the artistic vision of the director and everyone involved in created the film. "Full screen" formatting magnifies the film and does what the industry refers to as "pan and scan." An editor "pans and scans" the action that is on film in order to for it to fit a television screen. A more technical term is Modified Aspect Ratio (MAR). Film directors believe "pan and scan" is detrimental to their work because they believe that when a film is "pan and scanned", it takes away the artistry that was put into the film's frame and is essentially redirecting the film. It was largely used for VHS formatting and it was considered the popular choice to watch a film because it fit a television screen.
But as technology changes, so does the way we view film. While "pan and scan" was invented to fit televisions that had a more square aspect ratio, now the shape of televisions are changing. With widescreen televisions such as digital high-definition, technology is far more beneficial and kinder to films shot in widescreen format. These types of televisions eliminate the black edging on letterbox formatting that tend to annoy certain viewers but it is not intrusive such as "pan and scan." So it makes a more enjoyable and complete movie-watching experience for everyone and we can watch a film the way the director intended it to be watched.