Aperture has a 10,000 image limit per project. This does NOT mean that you can’t have more than 10,000 images in Aperture. Just that you need them in more than one project.
If you create a folder in the Project Panel (call it Project Folder) and then put all your projects (up to 10,000 images each) within that new folder, you will see what amounts to a multiple project - project. So if you had three 10,000 image projects nested within the new folder, you’d have a total of 30,000 images.
Photo Copyright Scott Bourne 2006 - All Rights Reserved