A UV filter will block out some of the Ultra Violet light which can make outdoor photos look washed out you can also try what's called a warming filter 1A. either way you should always have one of these two on your lense so it won't get scratched. a scratched filter is cheaper to replace than a scratched lense. a few others to try are an 812 which is very warm and you'll see when you look at it. the other filter most people get when taking outdoor photos is a circular polarizer, which will block out all light coming from coming into your camera from whatever direction you turn the filter too. you might try playing with these to start with. from there, look around and read about what filters do what. here's a site with some stuff about filters:
http://www.twistedtreephoto.com/filters%20we%20use.htmlremember Google is your friend!
Scott
