Originally Posted by
msbbarratt
It does seem rather odd that those marks are very obviously not there in the later photos. I cannot think of any plausible way in which 'burn' marks could disappear so cleanly yet be highly noticeable in that first photo. I think your explanation is correct.
I concurr that the diagonal lines are "zebras" to aid cameramen in monitoring the exposure.
As well as the viewfinder, such info can be selected so it is overlaid on the camera output or the recording.