my question is ,
does anyone know what Canon "does" when they take both the body and lens for calibration?
Yes, I was lucky and was invited to assist in the calibration of my gear. Canon support first calibrates your camera body. They use their reference lens to calibrate the sensor plane of your body to match their lens. The calibration value is stored in the camera (You cannot see that value in the menu or anywhere else). After that they start to calibrate your lens(es) with the help of a lensalign like setup. These calibration values are stored inside the lenses. They can calibrate for the wide end and tele end and every step in between in case of zooms. Off course all AFMA values that *you* can set in the menu are reset to zero before the calibration and have to be zero afterwards.
I sent in my 24-70II since I noticed that it's not as sharp as my friend's copy (we bought them one week apart). I also mentioned that it's back focusing and that I've tried using AFMA but haven't got it right and would appreciate if that can be looked at too. To my surprise I was told that AFMA "shouldn't be used" except for "special" cases. I said, that I've been doing it all the time with all my bodies and lenses. After I sent a complaint to the person in charge of after sales/ warranty, I got a call saying that the "bad focus" is because I set AFMA and that it's stored in the ROM of the Lens..
I dont know if this was a communication/understanding error on his part as Canon really stores these calibration values in the lens. That is something the end user cant do. AFMA via the menu is different as it is a user configuration thing. Perhaps he mixed that up.
My first words "Bull $hit" I couldn't help myself. It was obvious the person talking wasn't technical. I asked, so you mean to tell me that if I set AFMA for the 24-70II on my 1DX those settings are stored on the lens.. Reply.. YES.. .. I explained why this was complete Bull$hit.!! by asking "so that means, I can't use this lens on my other camera bodies.. SILENCE..
Long story short.. I was asked to send my my 1dx which they just "reset" ALL my AFMA settings and they re-flashed the ROM on both the 1dx and 24-70II and asked me to "retry".
I just finished testing using lensalign, (didn't feel like using focal pro). my manual testing resulted in (-4,-4).. Same as what I got with Focal Pro on the first day I got the 24-70II.
Well, Canon support is sometimes lazy and they just do nothing with your gear. They just send it back and pretend to have done something.
Any thoughts.. the CPS guy I spoke to wasn't very helpful.. He kept insisting that I should use the multicontroller/joystick to "SELECT the focus point"
Very helpful indeed...
you can imagine my frustration explaining DOF and that the little red square that's on the object tells me where I focused, and that object isn't sharp, hence SOMETHING is wrong. I asked him, do you take photos, he replied yes, I said I'm sorry but you're no photographer.. kinda mean, but I couldn't help it!!!!
Ok Rant over!!!!!!
I feel your pain. If you need help and they treat you like an idiot.