Mark Batten
Well-known member
Anybody have any ideas on this. 7d 2 with Grip. One battery Canon - the other third party. Using on a 500 f4 (Mark 1) with 1.4 Tele (Mark 3). intermittent fault of power failing and auto focus not working. Appears to work fine on other canon lens ie 17-40 and 100 Macro. No problems when using 1D X and 1D4 on same lens. Ta