CF or SD in 5D III

[Eaglewing]

I do understand the camera writes faster to a CF card but slower to SD card.

Granted the difference, I am interested to know how others make use of the two slots.

Would you use:

• Only CF
• Only SD
• Writing both to CF and SD in RAW
• Write to CF in RAW and SD in Jpeg

Note: I do not have the 5D IIII until I take delivery this weekend.

[RobertTheFat]

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@Waddizzle wrote:

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@RobertTheFat wrote:

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@Waddizzle wrote:

"That hideous misfeature is evidently intentional, as it is retained in the 7D Mark II."  

I would agree with that behavior.  The camera would either have to assume that you replaced the same card into the slot, or it would have to go through some elaborate routine in order to determine if the original card has been returned, without modificaitons. 

Without the camera continuously making a backup copy of the card ahead of time, it should not have any way of performing the latter test and determination.  The camera is forced to assume that you have inserted a new and different card, and rely on you to tell it what to do.

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I don't follow that reasoning at all. Nothing in the specs promises "a backup copy of the card". Indeed, in the case I cited, the cards are used consecutively, without any image file being written to both cards. So it doesn't make a particle of difference whether the same card or a different card is returned to the original slot.

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It shouldn't be too hard to follow.  Camera specifications has nothing to do with it.  In fact, the lack of "a backup copy of the card" in the specificaitons supports my conclusion.  Let me explain it in more detail......

If you remove a card from the camera, and then insert a card back into slot, should the camera assume that you have re-inserted the same card?  No, of course, not, which is why it makes no presumption about the content of the card, and must rely on you [as inconvenient as you find it] to tell it what to do with the fresh card..

Putting enough smarts into the firmware to recognize different cards would only take away memory space from the programming that creates the pictures.  Imagine that all of the computer instructions that run the camera must be written in 144 characters, or less. 

If given the choice between writing code to add bells and whistles [like recognizing re-inserted cards], or writing code to improve performace, which choice do you think they would make?  They would choose to include code that improved performance and force you to tell the camera what to do with a freshly inserted card.

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Obviously I didn't make my point clearly enough. Which is that if you want the camera to write to one type of card until it can't do so anymore and then switch to the other type, you should be able to take the active card out and put it (or some other card of the same type) back in without the camera countermanding your original instruction. And maintaining that behavior shouldn't require any tricky or complex firmware. Indeed, it strikes me as the simplest behavior to implement in a two-slot environment.

[jrhoffman75]

On the 1D Mark IV, if I select "Auto switch media" in the menu both cards show the same file type(s).

If I remove and replace a card it is still set to "Auto switch media".

If I remove the overflow card the menu selection is still "Auto switch media" but there is a warning that it can't autoswitch.

The only time the camera switches my selection is if I have selected Card 1 (or 2) as record/playback and then remove that card completely. Since there is now only one card in the camera it shifts the record/play to the installed card and has the same warning about can't autoswitch.

[RobertTheFat]

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@jrhoffman75 wrote:

On the 1D Mark IV, if I select "Auto switch media" in the menu both cards show the same file type(s).

If I remove and replace a card it is still set to "Auto switch media".

If I remove the overflow card the menu selection is still "Auto switch media" but there is a warning that it can't autoswitch.

The only time the camera switches my selection is if I have selected Card 1 (or 2) as record/playback and then remove that card completely. Since there is now only one card in the camera it shifts the record/play to the installed card and has the same warning about can't autoswitch.

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If you remove the card in the active slot and replace it before taking another picture, does the camera automatically restore that slot to active status? That's what I want the 5D3 and the 7D2 to do, but neither of them works that way. They immediately make the other slot active and leave it that way.

[jrhoffman75]

Yes. CF card in Slot1; SD card in Slot2.

Camera set to "Auto switch media" and "Record/play" to Slot2. (which makes CF the overflow card)

Remove SD card and replace it with an entirely different SD card - setting remains the same.

As an aside - if camera is set to record separetly and I write RAW to CF and JPEG to SD if I then switch to "Auto switch media" RAW + JPEG will be written to both cards.

[Waddizzle]

"Obviously I didn't make my point clearly enough. Which is that if you want the camera to write to one type of card until it can't do so anymore and then switch to the other type, you should be able to take the active card out and put it (or some other card of the same type) back in without the camera countermanding your original instruction."  

Why should the camera know what your exact intentions are?  There is no way that it can figure that out.  What if you wanted to do something else with the freshly inserted card?  How would the camera know what your intentions are?

[RobertTheFat]

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@Waddizzle wrote:

"Obviously I didn't make my point clearly enough. Which is that if you want the camera to write to one type of card until it can't do so anymore and then switch to the other type, you should be able to take the active card out and put it (or some other card of the same type) back in without the camera countermanding your original instruction."  

Why should the camera know what your exact intentions are?  There is no way that it can figure that out.  What if you wanted to do something else with the freshly inserted card?  How would the camera know what your intentions are?

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I would have to change the setting. All I ask is that the camera not conclude that my intentions have changed until I tell it that they have.

[slang]

This matter was really serious, card writing speed matter a lot. Thank you for valuable information.

[Eaglewing]

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@slang wrote:

This matter was really serious, card writing speed matter a lot. Thank you for valuable information.

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Indeed, and that is why I am interested to learn how others get around it. I do expect to shoot some events with CF cards in RAW and yet having the safeguard of a backup in the SD slot. And if I choose to record RAW (perhaps smaller files) on the SD card, how much slower will it impact the overall speed of writing to both cards and this I can only trial it when I have the camera with me. I may consider shooting medium size files in Jpeg on SD as a backup.

I am not shooting fast pace sports events so perhaps I can live with slower writing speed.

Despite a slower writing speed on the SD slot, I view it as an added bonus to be able to have an instant back up in a shoot. But of course this is my personal opinion and others may feel differently about it and that is fine.

Also I see the 5D III as more than just a camera that that has two card slots. I was first drawn to the 5D III because of its superior ISO, AF and multi AF points.

[TTMartin · Accepted solution]

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@Eaglewing wrote:

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@slang wrote:

This matter was really serious, card writing speed matter a lot. Thank you for valuable information.

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Indeed, and that is why I am interested to learn how others get around it. I do expect to shoot some events with CF cards in RAW and yet having the safeguard of a backup in the SD slot. And if I choose to record RAW (perhaps smaller files) on the SD card, how much slower will it impact the overall speed of writing to both cards and this I can only trial it when I have the camera with me. I may consider shooting medium size files in Jpeg on SD as a backup.

I am not shooting fast pace sports events so perhaps I can live with slower writing speed.

Despite a slower writing speed on the SD slot, I view it as an added bonus to be able to have an instant back up in a shoot. But of course this is my personal opinion and others may feel differently about it and that is fine.

Also I see the 5D III as more than just a camera that that has two card slots. I was first drawn to the 5D III because of its superior ISO, AF and multi AF points.

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While it is always best to shoot RAW, if all you have is a JPG it is not the end of the world. It is amazing how much latitude modern processing software gives you even with a JPG. 

For that reason I see little reason to shoot dual RAW files. RAW files to the CF card, and JPG files to the SD card is enough of a backup in my mind.

[Eaglewing]

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@TTMartin wrote:

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While it is always best to shoot RAW, if all you have is a JPG it is not the end of the world. It is amazing how much latitude modern processing software gives you even with a JPG. 

For that reason I see little reason to shoot dual RAW files. RAW files to the CF card, and JPG files to the SD card is enough of a backup in my mind.

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Thank you and I would flow with that - RAW files to CF and JPEG files to SD until when there is a need for a different configuration.

• I do have spare SD card -  Sandisk 32GB U1 class10 45MB/s.
• Purchase a new CF card -  Sandisk Extreme Pro 32GB 160MB/s UDMA7.