Use custom namespace in exiftool

[wlire]

I am trying to reorganize a bunch of my photo and video files, and for this case I am thinking of making a custom namespace. For example, I have some drone footage and would like to create an entry for the model of drone that recorded that video. I also want to have a spot to keep the original filename, because I will be batch renaming all of them in digikam and I want to have a spot to put the original filename just in case I need it. I would appreciate any help on how to get this done.

[StarGeek]

There are already preexisting tags that cover these.  The model of drone would be held in XMP:Model.  The original filename would be held in XMP:PreservedFileName.