" For the new 4k transfer, MPI used the original 16mm a/b film that the movie was shot on. It went through a five month restoration process at NOLO Digital Film in Chicago, with each frame being cleaned up digitally, before color correction – partially working from an earlier transfer by Hooper, and then the director gave his own notes. "MPI, they really committed," said Hooper, "and with the magic of 4K, what can be done in restoration was done.
It won't be an alarmingly pristine recreation: After all, the grime and the grit is an inherent part of 16mm. But it's the sound – from that eerie flash bulb creak to the buzzing, ripping sound of the chain – that Hooper believes will traumatize another generation of cineastes. He said, "The 7.1 sound is incredible, because it's really happening in your head."