I'm scanning a lot of old negatives but have now hit a batch of 30+ year old negatives that won't scan after the first cell. The others on the strip are scanned with pieces of adjoining cells. Upon closer examination I noticed that in the newer negatives, the cell dividers are clear. On the older negatives the cell dividers are black. My best idea at this point is to carefully cut the negatives apart and then put them in the negative holder with space between each cell. I looked to see if there's any type of setting to tell the scanner what the dividers are but have been unsuccessful so far. 35mm film is just that, there are no distinctions on the scanner.
Any good ideas? Am I missing something obvious?