Artist Nickolay Lamm has created a set of photographs that show how a cat's vision differs from humans. Cats can see 6-8 times better in dim light than humans, while humans have better day vision with more colors and resolution. The blurriness at the edge of the images represents peripheral vision.
To make sure that the photos were an accurate hypothesis of what cat vision looks like, Lamm consulted with Kerry L. Ketring, DVM, DACVO of All Animal Eye Clinic, Dr. DJ Haeussler of The Animal Eye Institute, and the Ophthalmology group at Penn Vet. For more, check out Lamm's blog, as well as this article from Wired.
Click on images to enlarge.