Monday, 27 October 2008
The eye doesn't see the world in an instant like a camera, because of the way the eye is constructed, we actually scan the world that we see and the brain builds a picture. At the back of your eye is your retina, the sensor that detects light. The density of the photoreceptors in the retina is not uniform like a camera sensor it is at its highest density at a tiny point called the fovea and rapidy drops. Just 4mm from the center of the fovea the density is just 5% of the density at the centre of the fovea. Try concentrating on a single letter in this article and try not to move your eyes, then without moving your eyes try and become concious of the words surrounding that letter. How much of it is sharp? Very little right? Your fovea only covers 2 degrees of your 180 degree field of view so most of your vision is blurred.
So if your vision is mostly a blur how do you actually see things? The eye scans the scene building up a picture and the brain fills in the gaps. There is enough detail outside the area of the fovea for you to notice contrast and the eye quickly flicks from point to point checking for things of interest. Some scientists and artists can predict the movement of your eye over an image.
I think the reason that I see the world in portait format is because I walk a lot. So I have a tendency to scan up and down to avoid obstacles in front of me rather than side to side. This may well explain why landscape format pictures don't come as easy to me as portrait. So many aspects of photography are about seeing the world in a different way and training the eye to see the things our minds gloss over like shadows, reflections and light, that I think it would be a good idea for me to train myself to start seeing in landscape format instead of portrait.
The Photographers Guide to the Eye