2007.07.02 18:00 "[Tiff] Old corrupted TIFF data - "Can not read directory count"", by Steve Bougerolle

2007.07.03 18:11 "Re: [Tiff] Old corrupted TIFF data - "Can not read directory count"", by Steve Bougerolle

I think I've cracked this. It looks like these were read improperly off CD originally. I re-read the original CDs using Windows rather than Linux (a tremendous moral defeat, that) and got back readable TIFFs that were longer than the originals and for which the directory offsets made sense.

It sounds like the Linux CD filesystem code has a bug.

Possibly, or it could be the Windows code that created the CDs originally.

However, I don't think it's that simple (either way) because I wrote many other files on CD around the same time and all of them read back fine. It's just the TIFFs that went bad somehow.