By default it keeps the photos in iCloud and only stores much smaller thumbnails on your local disk.
I've turned that option off because I wanted to be able to upload the images to S3 from the terminal, but if you just want to use it for search etc you wouldn't need to do that.
I've turned that option off because I wanted to be able to upload the images to S3 from the terminal, but if you just want to use it for search etc you wouldn't need to do that.