6k hmm? Sounds like they were happy with the Star is Born process and decided to use it for Ben Hur. I imagine Kane, Rain and the other A++ titles are also being done with the full 6k workflow.
AFAIK, 4k is highest resolution for record.
from Ned Price, in an auteurs interview about Doctor Zhivago last year, Warner printed 8k to film as a protection element (before restoring the film in 4k with a baselight): http://mubi.com/notebook/posts/1771 Quote Ned Price:
no, it is not Vista Vision, it's 65mm vertical negative shot through an anamorphic lens yielding an aspect ratio of around 2.76:1 65mm vertically has a native aspect ratio of around 2.2:1 vista vision, which was a horizontal negative, is 35mm film with a larger exposure area and an...