I believe the issue has been resolved. The second cam op was using SD cards instead of CF when I thought we were both on CF - so two totally different write speeds.Total record time is very similar from mark iii to mark iv
No Sir, it's set .mov "FHD 23.98" which the manual says is "full HD" or 1080p. 4K files sizes are even bigger (7min on a 32gb card - which was to be expected).
