From UA Libraries Digital Services Planning and Documentation
Documented problems with TIFF files
- “Value offset not word-aligned” caused by editing in Photoshop or Irfanview
- “Unknown TIFF IFT tag” caused when we rotate the image in Windows Photo Viewer, then close the program (it automatically saves the file, adding a private IFT tag to it).
- “Type mismatch for tag 700, expecting 1, saw 7”. None of these files are either valid nor well-formed. Caused by editing in camera raw after export. Critical error: must be repaired. One method is to use applyBridgeSettings.exe in Digital Projects\Administrative\forSoftware\Photoshop_Actions. Another method is to open in Irfanview and save as uncompressed TIFF, full size.
- Conflicts in imageHeight and imageWidth indicate an embedded thumbnail. For these files we are uncertain whether the dominant TIFF type is Exchangeable Image File Format (Uncompressed) version 2.2 or Tagged Image File Format version 6.0.
- On files edited with Microsoft Windows Photo Viewer, the identity conflict will be between "TIFF DLF Benchmark for Faithful Digital Reproductions of Monographs and Serials: color" version 6.0 and "Tagged Image File Format" version 8.2, which as far as we know doesn't exist yet (Exiftool 9.13 findings on this).
For more information, see Known_FITS_errors.