To all intents and purposes 16:9 is 1.85:1
The term "full frame" is traditionally given to source material that fills a 4:3 display either through being filmed that way or using pan&scan to resize the source material.
The movie/tv industry in league with the manufacturers of televisions agreed that 16:9 was a ratio suitable for the cinema and home display. This of course does not stop directors from using 2.35:1 for movies which of course will be 16:9 protected for the money making DVD and TV sales.
I've never really checked when a SKY 16:9 presentation of a movie has been sourced from a 2.35:1 ratio cinema print, it would be interesting to see how many are "adjusted" for TV broadcasting.
As for DD5.1 audio then yes every movie that has that soundtrack should be broadcast with in intact BUT that would mean more satellite capacity and more playout machines capable of supporting that format and SKY do not spend money unless it brings more money in.
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