Canon 5D mark II will not turn on with CF card formatted in Canon 5D mark III.

[macfawlty]

I have this issue quite regularly which I believe is the result of formatting a CF card in the mk III and then putting the card in the mk II. The 5D mkII will not turn on at all. I switch batteries, nothing. I take another CF card, put it in the mkII and it starts up fine. I was getting around it by only using the previously mkII formatted card in that camera, but I recently formatted in the mkIII and now it won't turn on. Both cards are Hoodman Steel 64GB UDMA 7 1000x.

[Waddizzle]

If you asked a question, then I most certainly missed it. I suggest doing a low level format on the card in a computer.

[macfawlty]

Sorry, I thought the question was implied in the description. My 5D mkII won't turn on with cards that have been formatted in a mkIII.

1) Why not?

2) What do I have to do to get the card formatted so that my mkII will turn on?

I tried a couple different formats from the computer. The 5D mkII will not turn on. With other cards not formatted in the 5DmkIII, it turns on and operates fine.

[RobertTheFat]

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@Waddizzle wrote:
If you asked a question, then I most certainly missed it. I suggest doing a low level format on the card in a computer.

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Yes, and make sure you format it to the FAT32 file system. It's a wild stab in the dark, but maybe the Mark III managed to format it in exFAT, a file system the Mark II can't grok. Yeah, the Mark III supposedly defaults to exFAT only for cards over 64GB, but you never know. The reformat costs you nothing.

[ebiggs1]

Why don't you just stop mixing up your CF cards?  Put one in one camera and the other in the other camera.  I don't see why it makes any difference but you answered your own question.  Didn't you?  I never remove the CF cards from my cameras.  They simply get replaced from time to time.

BTW, IMHO, 64gb cards are way too big.  Drop down to at least 32 and 16gb is better yet. 

[macfawlty]

Thanks for your suggestion.

I have multiple bodies and CF cards all over the place. It would be a bit impractical to have separate sets of cards for each body. Card data is transferred by a couple different editors after a shoot. And 64GB cards are essential when shooting video.

This is a sporadic but regular issue... obviously a problem when you're doing a multi-cam shoot and 2 of the 64GB cards won't work.

[Waddizzle]

"I have multiple bodies and CF cards all over the place. It would be a bit impractical to have separate sets of cards for each body." 

What is so impractical about that?  You don't do post processing in the cameras.  I assume that you store the image data somewhere, and that it all winds up at a common storage, or backup, location..  What real difference does it make what card is in the camera, when it is only a temporary storage location, anyway? 

I understand how you may shoot enough video to fill a card, and then need to use another to keep shooting.  But, it is what it is, until you do something about changing, or upgrading, camera bodies so that they are all the same, or at least all use the same cards....if that is what you really, really need.