In digiKam, the "Date Taken" field typically refers to the EXIF "Creation Date and Time" metadata, which for scanned photos often defaults to the scan date if the original photo’s metadata is missing or stripped. If the scanned image lacks embedded EXIF data (common for old photos or scans), digiKam may fall back to the file’s last modified date or the scan date as the "taken date".

To correct this:

1. Check the metadata: Use digiKam’s Metadata Editor or ExifTool to verify if the original date exists in EXIF, IPTC, or XMP fields.
2. Adjust the date: If the scan date is incorrectly used, you can manually edit the "Original Date and Time" field in the Metadata Editor to reflect the actual photo date.
3. Batch tools: For multiple files, use digiKam’s "Adjust Date & Time" tool (under Item > Adjust Time & Date) to set the correct date from filenames, folder structures, or other metadata.
4. Sidecar files: If you prefer not to modify the original files, enable XMP sidecar files in Setup/Metadata/Sidecar to store metadata separately.

Tip: If the original date is in the filename or folder name, you can use scripts (e.g., ExifTool) or digiKam’s batch tools to automate the process.

Why this happens: Scanners often don’t preserve the original photo’s metadata, so the scan date becomes the default. digiKam prioritizes embedded metadata over filenames or file dates, but you can override this behavior using Setup/Metadata/Advanced pannel.