WTF?! or how to be baffled by technology.

I have a very puzzling thing happening right now. I have two Transcend SD cards; one, a 32GB and one a 16GB. The 32GB card has ML on it. The 16GB card does not. I primarily use the 32GB card, in fact I have only used the 16GB card a couple times. A couple weeks ago, I had a hard time getting my iMac to read either card. It just acted like it wasn't inserted into the slot .I shut my computer down for a night and when I booted it back up, it would read my cards fine. Sweet. Then after that, every now and then it wouldn't read my card. I would restart my comp and it would work again no problem. Then, yesterday, I put my 32GB card into my 60D and it said "No Card In Camera." I pulled it out, shut the camera off, put it back in, turned the camera on - worked. Then today, it all fell apart. No matter what I did, I could not get my camera to say anything other than No Card In Camera. I tried my 16GB card, same thing. No Card In Camera. Must be my camera. I took it to the local shop, they said contact Canon.
Being that I had to shoot a music video tonight, I borrowed a friends t3i. When I got home and uploaded the footage, I thought I would try his card in my camera. What do you know, it worked (this one is a Kingston). Then I thought "what the hell," and I put my card into his camera. Son-of-a-bladder-buster, it worked. I tried the other, the 16GB, same, both worked. I put them into my camera, again, no dice. I tried them in my computer, no dice.
So, somehow, neither of my Transcend cards work in either my camera or my computer, but they both work in my friends camera. And, his card works in my camera, and my computer. What???
Is it possible somehow that my computer ruined the cards, but only for my camera? Side note: when I couldn' get my computer to read my card, sometimes I would plug the camera into the computer via USB and pull them off that way, this always worked. Are there evil impish creatures living in my cards, trying to ruin my life? Can anyone help me with this?

I find crushing the wretched things under a firm heel solves the problem of intermittent connectivity.

Haha. I'm not far off.

Go buy a new small SD card. Give that a whirl and see how it works. Fill it up and dump the card on the computer a few times.

Make sure you format the cards in the camera. Most of the time that solves the problem.

bigVinnie wrote in post #15050856
Make sure you format the cards in the camera. Most of the time that solves the problem.

Let me repeat for clarity. Format the cards in camera before you use them. After your shoot, download the images/video, and then put them in the camera and format them. I do that with all my cards and have never had an issue.

Scatterbrained wrote in post #15050893

Let me repeat for clarity. Format the cards in camera before you use them. After your shoot, download the images/video, and then put them in the camera and format them. I do that with all my cards and have never had an issue.

What he said!

I have formatted CF and SD cards in my computer for years and never had a problem. Its the only way I know of to totally format a card that's been used in another camera so it doesn't read the previous cameras file structure.

^^ +1. My experience too. I've always formatted my CF cards on the computer and never had a problem. I just moved over to SD and have been using the cards as received so far. When it's time I'll format on the computer again and don't expect any problems.

Tsmith wrote in post #15051991
I have formatted CF and SD cards in my computer for years and never had a problem. Its the only way I know of to totally format a card that's been used in another camera so it doesn't read the previous cameras file structure.

peter_n wrote in post #15053466
^^ +1. My experience too. I've always formatted my CF cards on the computer and never had a problem. I just moved over to SD and have been using the cards as received so far. When it's time I'll format on the computer again and don't expect any problems.

Me three. Maybe Canon has changed things so it's impossible to carry frame and folder numbering between cameras if you reformat in camera, but it certainly didn't used to be so. Since I still have some of those older cameras, even if lightly used, I reformat cards in the computer before putting them back in circulation.

Actually I think SD is different from CF when it comes to the formatting thing. I've downloaded the software to do it but haven't used it yet. There are instructions from SanDisk for CF, then there are different procedures for SD cards that are worth looking at. I've downloaded the software from the Secure Digital Association but I'm waiting for two 64GB cards to arrive before I experiment with one of my 16GB cards.

It is, and it isn't. CF cards are self-contained mass storage devices while SD cards have part of the drive controller (as distinct from the interface controller) in the card and the rest in the host device (camera here). But since we're formatting to initialize the FAT and directory structure, the lower-level details don't matter all that much. A formatted memory card will have the FAT and master directory reinitialized. With an SD card, you can also do a "low level format", which pretty well wipes the whole card surface, making lost file recovery next to impossible but optimizing the card for video recording where you need to spit out long files.

Note though that SanDisk's directions don't say "CF only". Also note that the SDA directions recommend not formatting in camera, or with your OS' formatting tool.