i've always had a suspicion my 40D might have some problem with focusing.. usually when i take landscape pictures. it doesnt seem to have the same problem with closeups (maybe me taking pictures at f/4.0 might be the problem..) take a look at these pictures and tell me what you guys think. 1. 17-85mm at approximately 50 mm, @5.6 2. 17-85 mm, approx 50 mm, @ 20 3. 50 mm, @ 5.6 4. 50 mm, @ 20 what do u guys think? i took these on a tripod, at 100 ISO and large JPG (although photobucket seems to be shrinking them down...) i know i haven used teh best lenses out there, but are these pics up to par?? in terms of clarity and sharpness? thanks!