of ATSC and aspect ratio???

[ceebee23]

Folks,

With US due to phase out analog broadcasting very shortly and the need for set top boxes etc to convert digital ATSC broadcasts to NTSC one issue I have not read about is the whole matter of 4:3, letterbox and 16:9 aspect ratios.

Here in Australia we use DVB-T which uses an anamorphic squeeze to deliver 16:9 images and when this is displayed on a 4:3 set the whole image is displayed looking something uncorrected like CinemaScope. Set top boxes have settings to provide 16:9, letterbox or a 4:3 center segment of the 16:9 image. (I assume the same options are available on US set top boxes).

But as I understand it ATSC does not use the anamorphic scheme ...so how do 16:9 images appear on a NTSC if 16:9 is set in the set top box.

What lead me to ask this arcane question was a comment on another board that complained many cable companies are simply using the 4:3 center section of the ATSC image rather than providing a proper letterbox version of 16:9 network broadcasts.