Synchronizing Metadata with External Programs
It’s also important to keep the metadata information synchronized between Lightroom and external programs such as Bridge. In the File Management preferences is an option to write all changes into the XMP metadata automatically. This feature writes to the XMP block header in the original file; or, in the case of proprietary raw files, writes changes to .xmp sidecar files. If you need to export the metadata explicitly, click the Metadata menu and choose XMP > Export XMP Metadata to File. If changes have been made to a file’s metadata outside of Lightroom, you can import the metadata by selecting Metadata > XMP > Import XMP Metadata from File.
An exclamation mark in the upper-right corner of a grid cell (see Figure 10) indicates a mismatch in the associated image file metadata. This isn’t as serious as it sounds. It just means that the metadata has probably been changed or updated by an external program. Click the exclamation mark button to open the dialog box shown in Figure 11. Then select Retry Metadata Export to update with the Lightroom metadata settings used most recently, or select Import Settings from Disk to update the settings using the externally modified settings information.
Figure 10 This warning indicator points out a mismatch in the associated image file metadata.
Figure 11 Specify whether you want to use the updated internal metadata, or import externally modified settings.