I started doing this when i went to a art museum and looked at a painting. That painting was blurry without me doing this, but i went to the other painting it was blurry to so i was concerned. But i knew i could do this, i started to see if it was normal by seeing if others could do this. but i was the only one. i cant hold it for more than 1 hour, or my eyes will be sore and then i have to sleep for a while. But im glade that there others that can do it. it's weird, isn't it?????