Have you noticed after you make a change to a RAW file — say adding your copyright info or a keyword or two — that sometimes a new file pops up in the folder? It carries the same name as the RAW file but with a different extension that reads XMP. So what is XMP anyway, and why is it in my folder of RAW files?
What is XMP?
XMP stands for extensible metadata platform. It’s a data standard that Adobe created when it introduced the original Camera Raw plug-in for Photoshop 7. Adobe needed to avoid corrupting RAW files by writing data into them. While that works just fine for JPEG, PNG and TIFF files, it is dangerous for RAW files.
RAW files — which are a form of TIFF, by the way — do not have standard places in them for writing new information like IPTC, copyright, adjustments for exposure or keywords, labels, ratings and so on. Each camera manufacturer decides where data is stored. This includes adjustments made by the manufacturer’s RAW processing software. Adobe saves these adjustments and other metadata in the XMP sidecar file.
Lightroom and XMP
Editing JPEGs, TIFFs, PNGs and PSDs in Lightroom puts the adjustments directly into the headers of each format. You might notice that adjusting RAW files in Lightroom does not create an XMP file. That’s because Lightroom is actually a database. Lightroom keeps the adjustment information stored there. The catch is that if an original RAW file is exported for use in another program, the adjustments do not go with it.
If you want Lightroom to create an XMP file, go to Lightroom > Catalog Settings (Win: Edit > Catalog Settings) then tick the “Automatically write changes into XMP.” This creates or updates the XMP sidecar file when any changes are made inside Lightroom.
Note that this will cause Lightroom to be slower especially on older computers with slow input/output ports. An extra advantage is that should Lighroom’s catalog (the database) become corrupt, it can be rebuilt simply by re-importing all the photos.
Excire Foto and XMP
Excire Foto, the great AI photo finding application, is XMP aware and it will read that data automatically. There is a decision to make. You can tell Excire Foto to always use sidecar files. This is not what it might seem. Excire Foto always writes data for RAW files into the corresponding XMP sidecar file. This setting creates sidecar files for all other file types, too. This setting should be left off.
Metadata and Excire Foto
Information that Excire Foto reads and writes includes keywords. If there are keywords in the XMP file, Excire Foto will read it into its database. Keywords added in Excire Foto will be written into a RAW file’s XMP sidecar. Other photo formats will have that information into their respective headers. No sidecar file is needed.
Keywords added in Excire Foto can be read by Bridge, Photoshop and, after they are imported into Lightroom’s database (Metadata > Read metadata from file). Conversely, keywords added in Lightroom can be read by Excire Foto after they have been exported from Lightroom (Metadata > Save metadata to file.)
Excire generates keywords using artificial intelligence. Excire’s AI added keywords are highlighted in blue. Keywords added by users or imported from other editors are presented in gray.
Labels and ratings
Color labels and star ratings from other applications and exported to their respective files (Lightroom for example) can be read by Excire Foto. Again, in the case of RAW files, these attributes are saved in sidecar files.
Reading and writing XMP metadata in Excire Foto
When ratings, color labels and keywords are added using Excire Foto, the data is stored in RAW files’ sidecars. If data is written to sidecar files outside of the app, it can be read by going to Photo > Load metadata. Any changes made outside of Excire Foto are added to its database using this command.
Changes made in Excire Foto can be exported for selected pictures by going to Photo > Store metadata.
Playing nice with Capture One, Luminar and Lightroom
Excire Foto’s ability to handle all keywords elegantly makes it a perfect add on to Capture One, Luminar and Lightroom for users that want to leverage artificial intelligence in finding and refining their photography.