I am getting a Canon 24-105mm f4 L. When searching the web I found all sorts of stories from people getrting dud 'L' series lenses (though mostly Canon 24-70mm L) so it seems a possibilty that I would like to be ready for.
So what do I do if I get a bad "copy" of the lens?
And, actually, how do you tell anyway if the "bad copy" lens is only a little bit bad copy and still better than the lenses you had before (which you sold anyway to get the new one)?
P.