Just got a 5D mk3 recently and I was watching one video that said "having a fast CF card and a slow SD card simultaneously in the mk3 will slow CF down to SD's speed".
This doesn't make sense to me. Yes I I chose the option to record to "Rec. to multiple" or "Rec. separately" than yes, it could slow down as it would record to both cards.
But if I have both cards in camera and choose 'Standard" or "Auto switch card" options and select Card 1 (CF) for "Record/play", wouldn't it mean it is recording to only CF card and hence why would it slow down the camera, or it wouldn't?
Any help really appreciated.