New exif tag: waterdepth

[Alan Clifford]

At the moment, I am using my own xmp uwdepth tag.  The logic I am using is:

- try to write uwdepth.
- if that write failed, try to write to an xmp sidecar file.

Following the same logic, would it be reasonable to:

- try to write to the exif tag
- if that write failed, say for a .mov file, just ignore the fail and carry on.

OK, a write might fail for another reason but this is just my own stuff and I can live with that.  It seems a tad pointless to try and identify all file types that might allow exif tags.

[Phil Harvey]

sounds like a 3 step process:

1. Try to write the EXIF tag

2. Try to write the XMP tag

3. write to a sidecar

- Phil