larryepage Loc: North Texas area

I have been a member of this site for almost two years and have read and followed countless threads bemoaning "corrupted" or "failed" memory cards. Some quick mental arithmetic comparing the number of supposed card failures against the relatively small group of members here and the almost nonexistent complaints of the 'spontaneous failure' of much more complex cameras and other systems among that group leads to a number of conclusions. The first is that if these cards are as unreliable as they appear here, there is no way that the companies that make them could remain in business. Most of the memory they make is used in applications much more critical than photography, and the cost of failures there would be unsustainable if it were as high as it is here. I've also had conversations at my local tech store (no...not Best Buy), and am told that they almost never see a failed memory card from any of their multiple thousands of customers. And memory cards that are used in cameras see much less stress than those used in computer systems.

So I am left with the conclusion that "It must be us."

Many here talk about how their photographic process is built around taking bursts or other continuous exposures with their cameras. Even cameras using fast memory do not write to the card instantaneously. They write to the in-camera buffer, which then writes to the memory card at a slower speed. And in some cameras, it can take as long as a minute or more to write a full buffer to the memory card.

My point is this. I believe that very few memory cards reported here as failed are actually bad. I suspect that most of these "failed" cards could be reformatted and reused. But I do believe that they are corrupted and that they have been corrupted by the users (us). Specifically, I suspect that the cameras they are in were powered off while still transferring data to the memory card. That will corrupt the card every time. I also suspect that some may have been corrupted or damaged by being removed while the camera is powered on. This is never acceptable, it doesn't matter what anyone's past experience is. It can cause power problems that scramble or damage the card or can interrupt data transfer between the camera and the card.

So...read your manual. Learn where your memory activity light is. Don't turn the camera off while that light is on. And turn the camera off before removing the memory card.

Thomas902 Loc: Washington DC

Yep... this "Don't turn the camera off while that light is on. And turn the camera off before removing the memory card."

TriX Loc: Raleigh, NC

And eject the card properly (insuring that all write operations to the card are completed) before removing from an external reader.

suntouched Loc: Sierra Vista AZ

And eject the card before removing from the computer. I have corrupted a couple of cards not doing this.

Longshadow Loc: Audubon, PA, United States

Longshadow Loc: Audubon, PA, United States

It can also happen with external disk drives. That's from experience too!

junglejim1949 Loc: Sacramento,CA

Don't think I made any of these mistakes but then again, maybe I did. These are great tips and important things to be aware of.
Thanks

User ID

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Like 99.99 of troubles experienced by
hogsters, it's plain User Error. And like
99.99% of same, this simple nonthing
will grow into about a half zillion posts.

.

Dikdik Loc: Winnipeg, Canada

Didn't know that... thanks

Dik

Longshadow Loc: Audubon, PA, United States

Which show that people are reading it.

Tea8 Loc: Where the wind comes sweeping down the plain.

My experience with my 'corrupted' card.

I shot some pics of a former classmate and their kids for family photos. They wanted someone cheap and since I wanted to dabble in getting better at photography I told them I would take some and they would have the rights to having them printed because I was learning as a photographer. We went to a park and I spent probably an hour or more taking different shots of them all over the park. I looked at almost all of the pictures in the camera and they looked fairly good, but then again most of them do. I completed shooting and then turned off the camera. I drove the 15 minutes home and took the card out of the camera and put it in the computer to start looking at them. Most of them were acceptable. Just needed some touch ups for flyaway hairs and such. Then I got to some of the images in the middle of the shoot. There were streaks in them where the color was much lighter than the rest of the picture. A couple of them looked like half of the photo was exposed properly and then suddenly the exposure changed halfway through the photo and it was twice as dark as the exposed properly part. It was only a few photos like that and then the ones from the end of the shoot were fine. So I used the photos that I could and gave them to them. (Yes, I was shooting jpeg. I didn't really know or understand raw at the time and have since given up shooting for other people, so I don't deal with raw now either.) Later on I reformatted the card and shot with it a bit. Didn't seem to have a problem, but I never really trusted it after that. So, I considered it in some way corrupted.

These days I couldn't tell you if I tossed it or if it's one of the old cards sitting in my card wallet that I might have to pull out in case of an emergency. (Yeah cause I have those laying around even though I'll probably never use them. Lol.)

So, chances are my card wasn't corrupted and just had some other glitch. It's part electrical and there are electrical glitches in those types of things from time to time. So who knows. Using the term corrupted is just easier to say. But overall, something happens to a card that makes us not really want to use it again whether it's actually corrupted, a fluke that happens, or something that's user error. (I have accidentally taken my card out before with the camera on and it's been fine; doesn't mean that won't change one day.)

So, what should we call it if something strange (to us anyway) happens to a card and we're not sure whether or not to use it again?

Longshadow Loc: Audubon, PA, United States

I've not had a card problem yet, but I can guarantee you if I suspected a card (not from something I did), it would be in the trash so fast...

TriX Loc: Raleigh, NC

NAND flash memory, which is what the cards are, can be corrupted by the particles generated by cosmic rays (which bombard us constantly. Doesn’t happen often, but if it flips one bit in the directory structure, it can cause damage. A rarity, but it does happen, which is why most enterprise servers use ECC DRAM (which isn’t flash but can be corrupted in the same way), while consumer machines typically don’t (as it is more expensive).

Longshadow Loc: Audubon, PA, United States

BTW - Static electricity can easily damage or degrade a card, and it will probably go unnoticed until it fails.

Tea8 Loc: Where the wind comes sweeping down the plain.

Well in those days, money for me was a factor in why I wouldn't just trash something. That has since changed and cards are cheaper now than they were then. (This was probably 5 years or so ago.) These days, I wouldn't really hesitate to trash a card if I suspected it being corrupted or causing me problems in other ways.