No this isn't going to be a post about what you should do when you feel the Grim Reaper knocking on your door!
The title refers to what your viewer's eyes will be doing instinctively. Take a look at this picture of the Nijo Ichiba seafood market in Sapporo, Hokkaido, Japan.
Firstly close your eyes for a second, open them up and then notice where your eyes go to first. I'm betting it was the rows of fish in the far left hand of the frame. Ever wondered why?
It's because they're the brightest part of the picture. Yes they are the subject of the image so, as in my previous posts, I deliberately kept them out of the centre of the frame so that you would look at them first and then follow the row of fish up to the rest of the frame.
But I also positioned myself so that the brightest bits of fish (directly under a light) were in that particular position to doubly enforce the idea that 'this is where I want you to look first'. I'm betting that quite a few of you didn't even notice that there was a man in the picture until a few seconds later.
The main aim of a good composition is to get the viewer to look where you want them to. One really effective tool to use is to have the main subject of the photo be brighter than the other bits around it. Here I've done it using natural light but you can also do it with a flash, a flashlight (or torch for those of us Commonwealthers!) or any other light-emitting gizmo.
Generally speaking you want to have the brightest part of the picture be not too close to the edge of the frame. The reason for that is that people will look at the bright part and then their eye will wander out of the frame. You want them to look at everything in the picture so keep the brightest part of the picture away from the edges, but not in the very centre, and people will look throughout the entire picture.