I'm trying to understand, why is it if I have a 1920x1080 file and I convert it for SD broadcast to Mpeg 2 (720 x 480) with a 4:3 aspect ratio, it is letter boxed. But if I try to export that same footage SD broadcast to Mpeg 2 (720 x 480) with a 16:9 aspect ratio it is either window boxed or pillar boxed.
I'm bit confused because they say that all Hd formats are shot in a 16x9 aspect ratio.
The Second question I also have is if you broadcast one of the HD formats in HD on a High Def TV, will it be fullscreen or Widescreen.