I know the PR book say you can PR a store to find what are you after, have you ever use it on finding people, I use it once when I am in a very busy station, and it is very hard to tell people apart, I am waiting for my parent and I know the kind of area they will came, so I state my purpose " My parent will appear at any moment and I will enter photofocus and when my appear in my eye sight, my eye will focus and move toward them automatically, my parent are wear....... and look like.....' and after 2-3min or so, my eye suddenly just focus and move to right hand side and there is my parent. I also try it on finding error in some area, such as there are letter A-Z and a extra letter somewhere in the wrong place and photofocus works very well and your brain just guide you towards it, I try on exam as well multiple choose Question, but it doesn't work very well...................