Canon Lenses On Ebay
What is the difference between a wide angle lens vs Wide angle filter?

There are several "filters" on eBay that only awarded at the end of your lens. They are relatively cheap. (Like $ 40-50) Here's an example: After http://cgi.ebay.com/WIDE-ANGLE-LENS-FISHEYE-CANON-EOS-DIGITAL-REBEL-XT-400D_W0QQitemZ200159672918QQihZ010QQcategoryZ106845QQssPageNameZWDVWQQrdZ1QQcmdZViewItem There are real lenses range from $ 300 – $ 4000. Thus: http://cgi.ebay.com/Canon-EF-20-35mm-f-2-8L-Lens_W0QQitemZ320165955825QQihZ011QQcategoryZ4687QQssPageNameZWDVWQQrdZ1QQcmdZViewItem I am assuming that the cheapest is a lower quality, and causes of the cartoons. How big of a difference is there, and there is a wide angle that could recommended for a novice photographer with a Digital Rebel XTI?

Well, as you saw, and correctly assumed the filters are definitely cheaper. With the be lower cost, you can expect to be lower quality optics as well as reduce the amount of light entering the lens. This can make it harder capturing the image. If you are taking photos of landscape, low light issue is not so much a big deal, but if your taking pictures at a party, using natural light can mean not get the shot. Under the optical quality means lower image quality too. Note that some of the most beautiful planes ever taken were performed using an art well below what is available today. It's really all the skills and the eye of photography. Now if this is for someone who just wants to learn and become a better photographer, then you can add a capability that may want to explore … good price at the moment and if you really want to go far, the $ 50 is a cheap way to learn who wants to carry it out. On the otherhand, for me and my shooting style, I know that enjoy wide-angle photography and I never buy a filter for me. I actually purchased an Tokina 12-24mm ultra wide for ~ $ 600 (with taxes, etc) my Nikon D70. HTH.