I just bought a 7D2 last week, and I have a question about writing photos to dual cards.
I have mine setup to write RAW to a CF card, and JPEG to an SD card, figuring it would be a nice way to have a backup while not having two RAW images floating around. My question is how this kind of setup affects the buffer size of the camera when shooting in high speed mode for sports. I was photographing my daughter's gymnastics and it felt like my buffer was filling faster than expected, and then I had to wait quite awhile for the buffer to finish writing before being able to view the photos (or take more).
Am I running into a shorter buffer because of the RAW + JPEG setting? I thought the buffer wouldn't be an issue here since I am writing to two separate cards (thinking that the card write speed would be the bottleneck). But it felt like it was filling about as fast as RAW+JPEG to a single card would be. My cards aren't cheapies by any means, but aren't top of the line either: Sandisk Extreme 60MB/s CF, and a Lexar Platinum II 200x SDXC.
If the JPEG processing is taking extra buffer space and/or slowing things down, would writing RAW to both cards be faster? Or should I just disable writing to the second card when shooting sports?