Interesting point! To be honest, I didn't consider that it might be more difficult to interpret the underlying filesystems and encodings in the future. My goal

Interesting point! To be honest, I didn't consider that it might be more difficult to interpret the underlying filesystems and encodings in the future. My goal was to get a lossless (well, as much as possible) archive of the disks since my time and physical access was limited. It is hard to predict what I will want to access in these images over the scale of decades, so my thinking was to leave them as untouched as possible, since I don't know what information will be important. That being said, a good guess would be that the most interesting data will be media files (especially old photos) and documents. For that data, your advice of collecting and re-encoding the files is wise. For the purpose of discovering the media files in these backups, I found my favored approach to be a brute force recursive search for file types. Exploring the original structure of the filesystems was interesting, but my intuition for where the valuable data was usually proved wrong.