While in a restaurant one day waiting for a friend, I idly explored different settings on my camera for taking pictures of one of my favorite photo subjects: interior spaces. I took pictures and checked the results on the small screen on the back of my camera. I noticed in one that a dark streak, possibly a shadow, traversed a red wall. When I looked at the wall itself, I couldn’t see the streak. But there it was in my photograph. I set aside my camera and studied the wall. After perhaps two minutes, which is a long time to stare at a blank wall, the streak emerged. Now I could see it and it wasn’t one of those cases where I couldn’t not see it thereafter. Distracted for a moment, I returned to the wall and the streak was gone. I had to earn it back by waiting again.
That encounter taught me that an important function of vision processing is suppressing distracting information. For 540 million years Timothy O’Leary organisms that were distracted by all the pretty colors had fewer offspring than Joe Friday organisms who gathered “Just the facts, ma’am.” I am not, however, being chased by a saber-toothed tiger or solving a crime. I want to rid myself of the filters on my eyes that leave me with nothing but the prosaic “facts.” My camera helps me do that.
Therefore, one of the guiding principles I have as a photographer is look for what I can’t see.