Question regarding writable file formats

[MOL]

Phil

I was looking at the file formats for which ExifTool provides R/W support the other day and wondered if there are any limitations when it comes to writing EXIF, IPTC or XMP tags to camera raw files.  Can I theoretically inject any tag into a CRW file for example, or are there certain limits (like writing to file only allowed for tags that make sense to change)?

Thx
Uwe

[Phil Harvey]

Hi Uwe,

Most RAW images are based on the TIFF format, so the same rules apply as for TIFF images.

CRW is a notable exception though, and only supports native CIFF and XMP information (the Canon utilities should be able to read this XMP, but I would be surprised if any 3rd party apps are able to).

- Phil

[MOL]

Hi Phil

Thanks for the info. I was aware of the CIFF format, but not sure about the usage of XMP with it.

Keep up the excellent work!
Uwe