well, long story short..
i purchased a used 70-200mm 2.8 NON-IS a couple of weeks ago.
There is some rotational play in the lens/body connection.
upon closer inspection, it is aparent that the locking hole where the pin from the body inserts into the lens is worn causing the play in rotation.
The rear Bayonet Mount needs to be/should be replaced.
So i contacted Canon tech and discussed the issue.
apparently, my suspitions about heavier lenses causing wear at this point in the camera body to lens connection are valid.
(a heavy lens can cause wear at the bayonet maount.
since the lens is out of warranty i can do the replacement myself.
the part number for the bayonet mount is CY1-2497-000-xxx
the (xxx) number on the part number is a measurement that describes the thickness of the bayonet mount. and that thickness comes in a range
from 1.5mm to 2.8mm in 1/10 mm increments.
i was told by canon that i have to remove the bayonet ring and measure the thickness to determine the replacement part number..
not a problem.
anyway, i have to wonder if that thickness affects the back/front focus of the lens.
Why would there be such a range in thickness for a standard production lens?
Does anybody have any insight into the raminifactions of changing the distance (via bayonet thickness) of the lens element to the sensor?
I am thinking about sending the lens to Canon for a calibration.
does anybody have a suggestion as to me either have canon replace the ring when i send it in or if i should replace the ringn before i send it in.
on a side note,
when i looked for the ring online, there is an EBAY seller selling the ring for $125.00 bucks.
when I contacted Canon Parts (1 866 481-2569) i was quoted the price of the mount at $31.77
thanks fo your insight!