Aperture - Password Protect a Project?
Aperture doesn't have that feature. It has been requested before, but it's not really an Aperture issue. Aperture is non-destructive so it never alters your raw or jpegs files, and these originals are stored simply as files in the file system, albeit slightly hidden with some smoke and mirrors.
Because of this you could simply use finder to browse and view the images. So password protecting in Aperture would achieve very little in the way of security.
Something that might work is to create a seperate library for the images you want to secure, and secure the container for that library.
I haven't tried it, but the following steps would probably work.
1. Create an Encrypted disk image that is read/write capable to hold your private Aperture library.
2. When not in use, keep the disk image unmounted, and don't keep the decrypt key in your keychain.
3. To open the private library in Aperture, first mount the disk in finder and supply the decryption password.
4. When the disk is mounted, Open the library from within Aperture.
5. If you created the disk image as read/writeable, you should then be able to make and save edits, and add new images.
6. When you are done, re-open your non-secure library within Aperture. Close Aperture, and unmount (eject) the disk image from finder.
As a theory it should work, but some types file systems support different features than others and so you may encounter a fly in the ointment somewhere in the process. Performance could also be an issue, as each time something is saved, the encrypted disk image is probably being updated.