Calibrating a camera body to fix a lens?
During my stay in Asia, I purchased a severely backfocusing EF 100mm f2 lens. I sent it in to a local Canon service center for calibration. After 5 frustrating months, they still couldn't manage to get it working. There's an 8-inch backfocus on the lens at a focus distance of 10 feet, and yet these people handed the lens back to me 3 times... each time claiming it had been fixed. Each time, I would physically demonstrate the problem to them at the service center, and each time they'd send it back claiming it was "fixed". Talk about sheer incompetence... sheesh.
So now they requested I hand over both the camera body alongside the lens. I know the camera body itself is working fine --- none of my other 4 lenses suffer from backfocusing on this body.
Is it normal for Canon service centers to require your camera body to calibrate a lens? I'm extremely dubious about this, especially considering how they've been trying to weasel their way out of fixing the lens for the past 5 months. I suspect that they were incapable of fixing something as simple as a backfocusing EF 100 f2 lens, and are trying to get around it by fiddling with my camera's AF system. Wouldn't that result in my other 4 lenses effectively front focusing with the camera body? Why would a Canon service center need my camera to fix a lens?