I just sent in my lense for calibration. The lady clarified the matter with me. She said that if you buy from authorise dealer the calibration will be done free, if not $80. The same applies to both local and overseas purchase. She said a lot of guys have been buying from Tin Cheung camera, it is not an authorised agent. Showed me many other receipts all from Tin Cheung, some buy 10 of the same lense. So they have to charge. I guess when people try to make money of out buying cheaper in Hkg and reselling here, they have no choice but to charge cos they end up with some many more lenses to calibrate. Too bad...