This was discussed several years ago when the DVD was released. If you remove the mag stripes from a 70mm print, the actual image AR is roughly 2.35:1 or so. The mag stripes actually cover the outer edges of the frame. The transfer was done from an unstriped IP, not from a release print, so the entire 2.35:1 frame was transferred for the DVD. Nothing is being squeezed or expanded here. You are actually seeing more of the image on the sides from the DVD than you would see from a 70mm mag striped print. Since the documentary was probably not sourced from the new transfer, that accounts for the AR differences.
Nonetheless they need to look for the original soundtrack (assuming Cinemax didn't erase it) or go back to the un-EQd print masters from which the soundtrack was derived before the HD version is released.
This would make a lot of sense, but the image I've used from the documentary was not taken from a previous transfer, but from a shot of an actual 70mm film strip, so we're really seeing the difference between the original film source and the DVD transfer. And the stretching on the DVD is very visible.
I've uploaded the source frame from the documentary here, it looks like a 70mm print without the mag soundtracks. You can see in the comparison that the DVD doesn't even extract the whole picture from the 70mm frame.
In the original thread, RAH was talking about the film restoration when he mentioned recovering the 2.35:1 area from the original 70mm. Looks like the Warner (or whoever did the digitizing) transfer group pretty much destroyed the original framing that RAH was striving to preserve. Probably just went with the default (safe) settings. I am really getting tired of these zoomed in transfers.
I wouldn't go that far - the transfer doesn't actually crop that much from the original 70mm frame, it certainly shows much more than some other transfers. It's not a question of framing, but of geometry - the extracted frame should have an aspect ratio of ~2.25:1 and not 2.40:1. It's a small difference, but I have no idea why Warner stretched the picture horizontally. I guess somebody pushed the wrong buttons during the mastering process. Hopefully they get it right the next time .