Hello all, A little over a month ago, I entered the DSLR world for the first time by purchasing the Canon EOS 40D. I must say that I LOVE this camera! Quite a big improvement over my old Fuji s7000 prosumer. Anyway, the lens I purchased to start off with is the Canon 1.8 50mm lens, and it is quite impressive for the money..but now I am looking for a lens with a decent wide angle with very sharp, and clear image quality. Right now, I have my eye on two lenses..the Canon 17-40mm L Lens and the Canon EF 28-135mm lens. I would love to get the 17-40 L lens, but my budget would better allow for the Canon EF 28-135mm lens...so here is my question; in terms of image quality, do you all think the Canon EF 28-135mm lens would offer a HUGE difference over the current 1.8 50mm lens I currently have, or would it just be a minimal difference at best? I already know the 17-40mm L would be a huge difference over what I have, but what about the Canon EF 28-135mm lens vs. the 1.8 50mm lens? Again, I referring to overall image quality, clarity, and sharpness. Thanks for the thoughts/comments in advance!