Imagine if you will, a huge camera shooting three rolls of film at the same time. Each processed film roll is individually contact printed to individual strips of film called matrix film; each of those are processed, dried, dyed with cyan, magenta and blue dyes and contact printed in registration on yet one more strip of film. A forth strip was often printed as well. That is how glorious Technicolor movies were produced and nothing today can match the process. The old camera thread started my brain.