Pan and scan

Pan and scan is a method of adjusting widescreen film images so that they can be shown within the proportions of a standard definition 4:3 aspect ratio television screen, often cropping off the sides of the original widescreen image to focus on the composition's most important aspects.

Some film directors and enthusiasts disapprove of pan and scan cropping, because it can remove up to 45% of the original image on 2.35:1 films or up to 53% on earlier 2.55:1 presentations, changing the director or cinematographer's original vision and intentions. The most extreme examples remove up to 75% of the original picture on such aspect ratios as 2.75:1 or even 3:1 in epics such as Ben-Hur, King of Kings or Lawrence of Arabia.

The vertical equivalent is known as "tilt and scan" or "reverse pan and scan". The method was most common in the days of VHS, before widescreen home media such as DVD and Blu-ray.

Center cut is similar with the difference as the name suggests that it is simply a direct cut of the material from the center of the image with no horizontal panning or vertical tilting involved. This method doesn't require the permission or availability of the film maker or director to identify the most important part of each frame. Most video displays have three options for 16:9 widescreen frame formatting, which are either center cut, letterbox or full frame. The first two options are reliant on the video stream's aspect ratio flag being set correctly.

For the first several decades of television broadcasting, sets displayed images with a 4:3 aspect ratio in which the width is 1.33 times the height—similar to most theatrical films prior to 1960. This was fine for pre-1953 films such as The Wizard of Oz or Casablanca. Meanwhile, in order to compete with television and lure audiences away from their sets, producers of theatrical motion pictures began to use "widescreen" formats such as CinemaScope and Todd-AO in the early to mid-1950s, which enable more panoramic vistas and present other compositional opportunities. Films with these formats might be twice as wide as a TV screen when televised. To present a widescreen movie on such a television requires one of two techniques to accommodate this difference: One is "letterboxing", which preserves the original theatrical aspect ratio, but is not as tall as a standard television screen, leaving black bars at the top and bottom of the screen; the other more common technique is to "pan and scan", filling the full height of the screen, but cropping it horizontally. Pan and scan cuts out as much as half of the image.

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