thanks dude.. but i do not have the manual as someone gave it to me. anyway, i read up abit about it, does it mean if i bring it to F1, my probability of getting sharp photos of the cars are higher?
My 400D dont seem to be able to AF. When i press button half down, the lens just keep shifting the focal point and cant get it right.. what is the problem? it happens to all original lenses that i have...