I just wondered if anyone has sent their camera and lenses in to Canon to get them calibrated? I think my macro lens is off as it was very sharp on my 400d until I upgraded to the 5d. I have tried loads of tests and although it is doesn't seem to be back focusing or anything it is not tack sharp. I spoke to Canon and they gave me the number of a representative in Glasgow, apparently it will be covered under warranty, they also said they can calibrate all my lenses. I thought this may be a good idea as all lenses will be covered but I am a little concerned about sending it in the mail. Any thoughts and is it worth it? Thanks