Shortened iMovie file same size as before

[macstatic]

In the attempt to make a shorter version of a movie I copied the 2 hour video file (28.52 GB) in Finder, opened up the copy which I edited by removing around half of it (effectively making it a 1 hour video), emptied the trashcan (in iMovie) and saved the file.
To my surprise the 1 hour video file has the same filesize as the 2 hour video! What have I done wrong?

I'm using iMovie 5.0.2. on a PowerBook G4 running MacOS 10.4.11.

 

[spinnerlys]

You use the 2 hour video as source footage, iMovie will use that 2 hour video to make the edits you have done and saves them to a "text" file, which has the information on what parts you did use from that 2 hour video. It will not actually remove the parts you didn't use from the 2 hour video file. If you want a new and smaller file, you have too look at the export options of iMovie.

 

[macstatic]

I see.
I didn't find any "Export" option, but there is a File-Share menu. Is this what you mean?

If so, what do I choose there? I assume "iDVD" just opens up iDVD and imports the video into it, so that won't change the file size of the movie. Besides, I want to keep the stuff I've done in iDVD as it is, with chapters and all (but having the unused parts removed), then save it again as a new iDVD file. I can't find any "iMovie project" format to export (share) to.