5D III Buffer: How best to utilize the memory cards

wallstreetoneil wrote in post #17925995
I found this out a few years ago - just shoot RAW to both cards separately, if you need the backup, it gives you more buffer than shooting RAW to CF and jpg to SD - it doesn't sound right but it is. Once I did the tests myself, I removed ever shooting jpg.

I'm not exactly sure what you mean by auto-switch, but I shoot RAW to each card separately - and yes when you do this you get more capacity than shooting jpg to the SD card - and since it hockey it would be insane to shoot jpg - raw and raw is far better than raw and jpg.

"Autoswitch" just sets it so that when one card is full it switches to the second card. It doesn't alternate saving images between the cards.

I had to read up on it, as I've never had that setting in a camera before.

neacail wrote in post #17925999
"Autoswitch" just sets it so that when one card is full it switches to the second card. It doesn't alternate saving images between the cards.

I had to read up on it, as I've never had that setting in a camera before.

Since I shoot weddings I always shoot both cards at the same time. I tested all the setups and, if I remember correctly, and this was surprising to me, that just CF alone, or CF + SD - both in RAW, the buffer capacity was the same - as long as you were using a FAST SD card.

Autoswitch to me is somewhat silly as this camera is an events camera and everyone I know shoots to both cards at the same time for backup.

If you don't care about backup - just shoot the CF card.

Auto switch was useful when we didn't have affordable large capacity cards and saved us switching out cards.

wallstreetoneil wrote in post #17925695
When I had my 5D3s I tested it - it matters. Made about a 3 shot buffer difference.

rrblint wrote in post #17925702
Glad that you got such a good performance increase, but all the other accounts that I've read say that it makes no difference. I can only rely on written reports of people that I trust as I don't have a 5D3 to test it on.

I finally found my 1000x SD card, popped it into the 5D3 along with the CF card, then tested continuous shooting. I ended up getting 2 more shots (12 instead of 10) than with the 400x SD inserted. Not bad.

frugivore wrote in post #17927582
I finally found my 1000x SD card, popped it into the 5D3 along with the CF card, then tested continuous shooting. I ended up getting 2 more shots (12 instead of 10) than with the 400x SD inserted. Not bad.

Very cool. I'll revise my notes.

frugivore wrote in post #17927582
I finally found my 1000x SD card, popped it into the 5D3 along with the CF card, then tested continuous shooting. I ended up getting 2 more shots (12 instead of 10) than with the 400x SD inserted. Not bad.

This still seems a few too low. Are you shooting RAW to both cards? Or RAW to CF and jpg to SD.I know it is file size dependant based on ISO but I remember the number being a few higher than that.

wallstreetoneil wrote in post #17927765
This still seems a few too low. Are you shooting RAW to both cards? Or RAW to CF and jpg to SD.I know it is file size dependant based on ISO but I remember the number being a few higher than that.

Yes, RAW to both cards. And it was done in a low light environment so high ISO, which would increase the file size. In ideal conditions, I'm sure I could get a few more squeezed out of it.

Frugivore, what are the exact write speeds of the two cards that you are using?

Both SD cards are Lexar pro. The 400x is 20MB/s. The 1000x is 80MB/s. These are write speeds.

The 800x CF card has 75MB/s write speed. It's not a lexar.

Interesting, I suspect that the slight difference you guys are seeing is due to the 400X card being in reality slightly below the 20MB/s nominal rating say maybe 18.6 MB/s and the 1000X card then provides the full 20MB/s that the camera is capable of. I'd like to see a 40 MB/s card tested against the 80 MB/s card and see if there is any difference there.

The card that I suggest, the 95 MBit Sandisk Extreme Pro, I will bet $1, will do even better. I did some testing with the 5D3, 7D2 and 5 DSR and I found, not everytime, but it is faster than the 800x cards. For the 5dsr I use the 1066x CF cards and the Sandisk 95MBit SD card.