Just downloaded the most recent firmware update for the 5D3 (released Nov. 2016. Firmware 1.34 I think) and now my camera is writing to the SD card very slow. Takes about 3 seconds per picture on full raw. I'm using a new SanDisk 32gb 85 Mbps card and also a lexar 32 gb 95 Mbps card. There was no difference in write speed between the cards.
Using my 16gb SanDisk 30 Mbps CF card it writes instantaneously.
Before updating the firmware (came from firmware 1.23) it wrote instantaneously even when burst shooting and using dual cards. It's very frustrating during events when I'm trying to quickly review pictures and have "Sony a7-like" write times. While writing the pictures I can see very pixelated previews of the images but it takes forever to get full res reviews.
I also was noticing lag/unresponsiveness in changing AF modes but this will need further looking into before I blame it on the update.
Is anyone else seeing very slow write times after the update?
