Input comes from Panasonic 4K (Consumer Camera) here HC-WX970 or HC-VX870 (2015)
i think it was the most advanced on that set it was only 1 and she black dress is the main leader of it the other is most probably a Sony Full HD
so very probably to maintain sync easier without to much resolution interpolation (complex todo in perfection at that time) the decision was made to sync on 1080p (internal or external down-scaling)
In theory that specific ms black dress camera view could exist in native 4k but its very unlikely for this specific production.
