Today’s Question: You said: “That means that by using keywords (and saving metadata for my photos out to the actual files on my hard drive) I can still have access to that information even outside of Lightroom [or Photoshop].” Would this apply to RAW files?
Tim’s Quick Answer: Yes, Lightroom is able to save standard metadata (including keywords) to raw captures as well as other image file formats (such as JPEG and TIFF). The difference is that the metadata is written to an XMP “sidecar” file in the case of a raw capture, compared to the actual image file for other file formats.
More Detail: Today’s question is a follow-up to a previous answer related to saving metadata to the actual files, rather than only in the Lightroom catalog. I had indicated that saving metadata to the actual image files provides a backup of most of the information in your Lightroom catalog, and also makes it possible to view your metadata with other applications (such as Adobe Bridge).
Lightroom can save metadata to files for all supported image formats. The only difference is where the actual metadata is saved. For “standard” image file formats (such as JPEG, TIFF, and even Adobe DNG), the metadata updates will be written to the image file itself. For proprietary raw capture formats, the metadata will instead be written to an XMP sidecar file.
It is important to keep in mind that all metadata from Lightroom is not saved to the image files when you use the “Save Metadata to Files” command from the Metadata menu (or enable the automatic writing of metadata in the Catalog Settings dialog). Lightroom-specific features such as pick and reject flags, collections, and virtual copies will not be saved to the image files.
Only standard metadata values and the Develop adjustment settings are saved when you use this option. That said, I’d rather have most of my information backed up and available to other applications, as opposed to having that information only available in the Lightroom catalog.