The easiest way i found to do, this was to use the 3d cross-eyed technique. All the differences seem to pop out at you. Here is a link to learn how to view the images in 3d
http://www.neilcreek.com/blog/2008/02/28/how-to-see-3d-photos/
WARNING using this technique can hurt your eyes after awhile, and not everyone will be able to do it.
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