iCloud preferences

Use the controls in the iCloud preference pane to turn My Photo Stream on or off for an Aperture library, as well as set options for automatically uploading and downloading photos between your photo stream and your Aperture library. You can also turn on iCloud Photo Sharing to share your photos with others. For more information about sharing photos, see Sharing photos overview.

Figure. Photo Stream pane in Aperture Preferences window

The iCloud preference pane contains the following controls: