Recording to dual CF and SD cards slows 5d mk3 down?

CyberDyneSystems wrote in post #17610251
Hey, this thread is for the Old masters, we have Davinci and Van Gogh!!!

Ha, nice catch! It didn't register with me before. I guess I was too focused on CF and SD cards.

It definitely does not slow down having the SD card inserted. I keep Magic Lantern on the SD card, where the camera just reads from. No performance hit at all.

-Botticelli

What is the difference between "record separately" and "record to multiple" Which is faster? I like writing RAW to both and it seems as though both can be done under either method.

Silver-Halide wrote in post #17610274
What is the difference between "record separately" and "record to multiple" Which is faster? I like writing RAW to both and it seems as though both can be done under either method.

With Rec. separately you can set the image quality for each card. For example, you can record RAW to the CF card and JPG to the SD card. With Rec. to multiple, the image is recorded to both cards simultaneously with the same image quality. If you like writing RAW to both cards, use this setting. As for speed, the write speed will default to the slower speed of the SD card with both settings. However, if you use Rec. separately and the image quality settings are different, Canon even notes in the manual that the "maximum burst will decrease greatly."

ThreeHounds wrote in post #17610265
It definitely does not slow down having the SD card inserted. I keep Magic Lantern on the SD card, where the camera just reads from. No performance hit at all.

-Botticelli

That sounds like a nice setup for the SD card with Magic Lantern. Do you have to change any other settings?

Oh, and welcome master Botticelli!

No, Just copied the ML files to the SD card. The 5D mklll looks to the 2 cards for boot info when it starts up. Only thing to remember is to reformat the SD card according to MLs instructions if you want to remove it. Otherwise the bootflag will remain set in camera to look for the card, so it won't boot without the card = brick.

CyberDyneSystems wrote in post #17610251
Hey, this thread is for the Old masters, we have Davinci and Van Gogh!!!

Haha lol

The slower SD speed was never really a problem for me until I went whale watching last week - I missed a few shots because my buffer was taking forever to clear...

Morning All.
Had a 5dMk3 for over two years now and i love the results. Just had this Slow SD recording experience. I didn't realise that the SD slot was a 'basic' speed. Im using both slots and the cards a are Scandisk extreme pro 16gb, the CF card is 90mb/s and the SD is 95mb/s and have set the camera to automatically save to the SD card when the CF is full.
Shame you cannot program the SD slot to automatically record movie only as it is clearly of no use to record multiple images at any great speed.
Does anyone know if the SD slot on the 7Dmk2 has the same specification as the 5mk3?
I assume the 1DX having two CF slots has no issues of this nature?

SD Card slot on 7D2 is faster. I do not however have the actual write speeds off the top of my head, only that it was improved vs. 5D3.
It is still slower than the CF card.

I don't follow.
- The SD card will not be used for storing images unless you set it up to do so.
- The SD card is very clearly of use for still images, I have made good use of the secondary SD card since I got my first 1D2 back in 2005. The cameras buffer still allows a lot of shooting to take place before anything slows down. It was no so long ago that ALL card interfaces were too slow to keep up, and the camera buffer was the only thing that mattered in this regard. Now both card speeds and buffers are bigger and faster, and we are shooting a lot faster to more images that ever before.

Thank you for the reply. I admit that the SD card is of use to store still images, but for me, due to the writing speed not as good as the CF slot. A lot of my photography is in servo/continuos shooting mode and after 5 frames the camera buffers on the SD slot. .
I have now turned off the automatic card recording mode for this reason and will not use the SD card unless i am forced to.