I have noticed something strange. 1DX, GP-E1, 70-200 II with 2X.
I had the camera at a 45 degree angle, so half way between landscape and portrait, the IS system was making noisy and I was unable to auto focus.
I switched the camera off , back on again --> everything fine, up to about an hour later when I was pointing upward to take a shot of a bird high in tree.
It looks like that at certain angles ~ 45 degrees the GP-E1 gets confused.
I tried without the GP-E1 and I am unable to reproduce the "problem"
1) has anybody had the same problem?
2) is the GP-E1 info used for IS?
This is a minor problem, just switch camera off on and it is solved. I am just curious?