I am unhealthily addicted to shallow depth of field (actually is there such a thing as a healthy addiction?). I can't seem to stop down the lens and shoot with some depth (with very few exceptions). It means that any photos I take have a subject and then some blur. They almost never have a background. Actually, I suppose a lot of this has to do with the fact that I pretty much only shoot with my 50mm lens now... which is the equivalent to an 80mm on 35mm with the 1.6x crop factor. So it will be a big difference when I buy the 17-40mm again. I guess I shouldn't have sold it, but at the time I was convinced that f/4 was just too slow for me to use. I know better now, and if it gets dark then the 50 1.8 comes out. Simple.