Inconsistent results when exporting projects as new libraries

Question

I am trying to export a project as a new library without the original ("master") images and am getting inconsistent results. Each time I've tried this, I am careful not to check "Copy originals into exported library". Sometimes it works exactly as expected -- i.e., a new library file is created and, when I examine the contents of the new library, there are no master image files. Other times when I examine the new Aperture library file, I find that it contains master image files. Indeed, sometimes, the new library contains more master image files than there are images in the project from which the library was created.
What am I doing wrong or missing? Is this normal behavior?
(Aperture 3.4.3)

Answer 1

After a bit of exploring, here is what I determined:
1. Most of my projects were created by importing images from a folder without moving the original images (Files> Import> Folder as Projects> Store Files: In their original location). Using this method, the images in the project are all referenced images (i.e. the originals are not moved or copied into the Aperture library). When later export these projects as described above, the resulting library also does not contain any of the original image files or masters. This is my desired state and for most of my 2012 projects exactly what happened.
2. If, however, any of the images in a given library were originally imported so that the master image resided in the Aperture library and that image was subsequently deleted, then the exported library will still contain the masters.
The solution I found was to open the exported library file and empty the trash (Aperture> Empty Aperture Trash).
(Of course, the longer term solution within my given workflow is to be careful not to import the masters at the beginning of the process.)
Hope this helps someone.