Removing items from TM

Is there any way to selectively remove backed-up items from the TM archive? In this case, an entire folder on an external HDD.

Sounds silly I know, but there is a reason- I want to add some information to the headers on most of the movies in the iTunes library, and it's going to mean TM will see about 150GB of changed files for the sake of a few KB of extra data, and I haven't got an enormous amount of spare space on the TM drive...

I'd much rather remove the old ones and let TM save the new ones after editing, but can't see any way to do it

Have you tried this?

That looks just the job, I hadn't realised Finder had a different set of actions in TM.

Thanks

That worked, but it seems you need to be careful with TM .

First thing I did was to put the entire external drive (about 280GB of data) into TM's ignore list, then went ahead with all the edits on the movie files.

Turned TM off, went into TM and deleted the folder with the unwanted files in it (about 150GB), removed the drive from the ignore list and turned TM back on.

When backup time arrived, it went into a new backup of the entire drive...

So if anyone else tries this, I'd suggest you only 'ignore' whatever you're later going to delete!