My understanding is that the standard practice in TV isn't to use anamorphic lenses. That means that you shouldn't see a noticeable difference in grain from "Broken Bow" compared to the rest of the season - even when they knew they were shooting for 16:9, that image would have been extracted from the 4:3 frame, same as "Broken Bow" was.
If that's true, then I'd suggest there must've been a much tighter 16:9 frame extracted than they settled into as the series progressed.
It must just be me then. Having focused on the extras, I'm ploughing through the episodes more slowly and besides the Pilot, have only had time to watch "Fight or Flight" and a random viewing of "Terra Nova" which wasn't as noisy. I know it's absolutely a creative decision, to overexpose the picture during scenes with Young Archer and his Father, pumping up the brightness to give it an almost sepia tone and making the grain the worse it can possibly get.
It's a dull subject but if it were possible to make a case for including the extra option of viewing an alternative 4:3 master for "Broken Bow" in particular (if it even still exists), it might be worthwhile to see the Director's initially composed shots.
A bit like sometimes, how you'd get two versions of films like The Searchers or Touch of Evil included, because they were either planned to be seen or exhibited in different aspect ratios.
Originally posted by Lee R over at Roobarb's Forum
Many shots show a preference for taking the 16:9 matte higher in the frame.
Some scenes, like this effects shot, are equally pleasing to the eye in either ratio.
Others would appear clearly composed for 16:9. Here the open matte 4:3 version has just empty space to the top and bottom of the frame. Note that the credits have been created separately for both versions.
Interestingly, other shots have a much more pleasing composition at 4:3 with the widescreen version looking a little cramped here.