The attached negative scan shows a thin curved line running along the full length of a roll of 120 Tri-X. It was scanned by x-ray on my outward flight and to avoid the possibility of encountering a CT scanner on my return flight, I instead sent it home by DHL, who informed me they only x-ray packages and do not use CT scanners. I travelled with 20 rolls of the same film and only two of them have this line. Any thoughts?