Memory Cards - How to Extend Their Life and Keep Them Healthy

Memory Cards – How to Extend Their Life and Keep Them Healthy


Love ‘em or hate ‘em, without memory cards our digital cameras would be as useful as a tap on a turnip.

Fuji 2GB XD Picture Card.jpg

And not only cameras: the cards are also found in PDAs, mobile phones, go-anywhere music players, robotic dogs, printers and laptops … even TV sets have card slots.

Many modern cameras build in significant amounts of memory so we can head out for a shoot without a moment’s hesitation. Yet the size of images today coupled with the digicam’s emerging talents as a video camcorder means that we need big dollops of portable memory.

CF card opened.jpg

They’re ultra small, decidedly clever, mostly reliable and offer remarkable storage capacities. But beware of their fragility … mistreat them and they’ll snap back with distressing damage.

Plamen & CF card 1.jpg

To dig out a few facts on the technology and the use of memory cards, I spoke to Plamen Pazov of Xyber Technologies in Sydney, who helped with this story. His business is data recovery.

Memory cards rely on an implantation process which forces the electrons into an insulating layer within the chip itself. They get trapped there.

Because of that process of implantation, earlier memory cards had a very limited lifetime. Current ones are a lot better and reliability has increased to about a million write cycles.

MMC & SD cards.jpg

Now the tricky bit: a single write cycle is not merely the action of writing a single image to the card. The cards write a single block at a time; this may total a couple of kilobytes each.

Even if the computer is not interfering with the data on the card it still continuously accesses the card. This action is similar to a write cycle. The longevity of your card is directly affected and can be decreased quite significantly.

Plamen, in his experience, has heard people say they’ve plugged their card into the computer and started reading the image directly from the card: “If you think about how many millions of times the computer will be accessing the card just to read parts of the picture, by reading and reading and rewriting — even small changes — you might reduce the card’s life expectancy by half just by reading a single picture.

Some helpful tips on extending the life of your card:

  • The best approach is to load your memory card, copy the images on it directly to your hard drive. Then take the card out.
  • Keep the card in the computer no longer than necessary. Do the image downloading from the card, then extract it. Left in the computer it will continuously access the directory, checking the byte order, to see if there are any changes etc. This action is identical to a write cycle so the life of your card is reduced. Don’t work on the image while it’s still on the card. You could easily knock out half of the life expectancy of the card just by doing that with a single image.

CF card & reader 2.jpg

The message: load your card, copy the images from it directly to your hard drive. Then take the card out.

Bye Byes?

Now at this point, I posed the question: if my pictures are ‘lost’, have they really gone?

You must remember that a card is a removable device as far as the computer and camera are concerned. It behaves in the same way as a small hard drive.

The card has an area called the directory. That area is very important as it keeps track of the files on the disc and on which sectors they’re written.

While that information may be missing, the rest of the data is still there but can’t be retrieved. Damage the directory and the card is useless — but you can’t access it in a meaningful way … the files are no longer complete entities.

The directory is ultra important. Many of the problems people encounter are caused by a damaged directory: it may have been overwritten or there’s a hardware problem with the card … some sectors cannot be read.

More tips to keep your memory card healthy:

After a shooting session, download the pictures, then reformat the card in the camera. The camera then writes a clean directory, dispensing with leftover and unrelated entries. Reformat the card frequently.

If you have accidentally erased the card in the camera, the pictures may still be recoverable. It’s only when a camera has performed a ‘long erase’ that you may be unable to recover the images.

Check out Part 2 on this exploration of Memory Cards here.

Read more from our Cameras & Equipment category

Barrie Smith is an experienced writer/photographer currently published in Australian Macworld, Auscam and other magazines in Australia and overseas.

Some Older Comments

  • Tyree October 19, 2010 01:58 am

    I know this is a question that could have a very broad answer but how long on average will a compact flash memory card last? And how often should I replace it?

  • scott April 26, 2010 12:08 pm

    One tool everyone should have is Teracopy. I use it to copy the files from the card to my HD before I work on them. It is a LOT faster than the Windows copy, and it is also free.

  • thuy May 15, 2009 12:49 pm

    Thank you machinedog. Only if it could give me an accurate reading. Oh well.

  • MachineDog May 15, 2009 07:01 am

    "Has anyone had an issue with SanDisk Extreme III not reading the right capacity in their cameras? I have a Nikon D80 and a 8GB SanDisk Extreme III. When I put the card in blank, it says I have over 651 images that I can take. However, I have gone over that amount. Is there any way I can fix the card reading?"

    Image sizes can range depending on what you're taking a picture of, to my understanding. If your picture is an all-white picture it'll take up far less space than one with a lot of color changes. That's why it's only an estimate.

  • Biomech May 15, 2009 05:35 am

    It's also worth pointing out, in regards to data recovery, that when a file (data) is "deleted from a storage device such as a memory card or harddrive, that data is merely marked as unrequired. The data is still there but the system knows it is available to be used if required. There are various applications around for recovering data that has been deleted and they work very well (I've done 2 huge harddrives in as many years). The system wont use this space unless it needs to, this is why so many hard drives can be picked up on ebay and have the sensitive data recovered. You might not write over that deleted file for 20years!

  • Anita May 15, 2009 12:30 am

    What does all of this mean for the new Eye-Fi card? information is being sent from my card to my computer every time my camera is ON in my house. Is it being read or does that count as a "write". Do these cards not last as long?

  • thuy May 14, 2009 02:39 pm

    Has anyone had an issue with SanDisk Extreme III not reading the right capacity in their cameras? I have a Nikon D80 and a 8GB SanDisk Extreme III. When I put the card in blank, it says I have over 651 images that I can take. However, I have gone over that amount. Is there any way I can fix the card reading?

  • Danro May 12, 2009 08:00 am

    Never forget the electrostatic discharges if you are wearing nylon or synthetic clothes. This could damage a flash card as i know. It is good to avoid touching the contacts of the card. But nobody noticed (underlined) this....

  • Fredshome May 11, 2009 07:05 pm

    Will above says it all, really. The only real risk with memory cards is substandard units from strange brands that fail unexpectedly (aka write-only cards). Buy regular brands (Sandisk, etc.) and that problem goes away.

    Current flash memory is pretty much immortal for practical purposes if you don't abuse the hardware.

  • Will May 10, 2009 10:01 pm

    Thanks for telling us who you got these tips from. I'll make sure that whenever I need data recovery around Sydney I avoid this guy entirely.

    Some of the information given in the article *may* have been relevant five years ago, but is now hopelessly out of date.

    "you might reduce the card’s life expectancy by half just by reading a single picture." - this is completely misleading, the only reason reading a single picture could reduce a card's life expectancy by half, is if it was already dead.

    Except in the case of very snap-happy photojournalists, modern multi-GB flash cards will outlive the cameras they're used in by several orders of magnitude.

  • Fletch May 5, 2009 10:20 pm

    The photo of they guy holding the San Disk CF card has photoshop disaster writted all over it! Was it really necessary?

  • MeiTeng May 5, 2009 05:10 pm

    Thanks for the tips. I have only recently discovered the need for reformatting of memory cards.

  • Peter May 5, 2009 12:26 pm

    More to the point, by the time your memory card wears out , you will have changed your camera. I am presently on my 4th camera of which each has a different type of card.

    Secondly, when you format your card in the camera, it doesn't actually erase the images, it only knocks out the headers, exactly the same as deleting the images. You can still recover the images after a format. So just delete them when you have downloaded them to your hdd.

  • David Anderson May 5, 2009 08:04 am

    LOL. Stupid article. By the time the memory card wears out - it will cost $4.99 to replace it.

    What is the point of this article?

  • Dezzysean May 5, 2009 05:33 am

    Just read, "Memory Cards - How to Extend Their Life and Keep Them Healthy",......
    One more thing I would add to; after loading your files to your Hardrive is to copy it to another source, whether that's on CD/DVD or an external hardrive. This way you'll have 2 separate copies of your files...then I would format my card in the camera. Just a thought...!

  • Anton Piatek May 4, 2009 08:18 pm

    Write cycles are what wear out a flash - you can read as much as you like. So leaving the card in the pc is not a problem.
    It is definitely a good idea to copy the pictures to your disk first before editing them though.

    The best way to prolong the life of your cards is to look after them. They are more likely to be broken by mistreatment than by running out of write cycles (when used for a camera anyway - there are other uses for CF cards that will wear them out in write cycles quickly, but a camera is not one of them)

  • iugradmark May 4, 2009 03:58 am

    Can someone recommend a good reader usb interface for Nikon CF cards?



  • Tim May 4, 2009 02:11 am

    The whole idea that leaving your card connected wears it down is absolutely ludicrous. As the previous poster said, that's a 'read' (unless of course you are editing on the card). A single 'bit' of flash memory (8 bits to a byte) can handle a little over 1 million WRITEs before it degrades to the point were it becomes useless. A read does not interfere with this process. In fact, that's the whole point of flash memory.

    Flash memory is 'non-volatile'. That means that once you set the bit, it will stay there for practically forever. You can also read it as many times as you wish. This is in contrast to volatile memory (like RAM in your computer).

    Most flash controllers (the extra circuits built into your memory card) are also pretty darn smart. They distribute the writes as neccessary. Each time you write data to a card, it's not always the first bit that gets written. The controller mixes things up. That way the card will last for a LOT longer.

    As an electrical engineer who characterized the electrical properties of these devices, I find that claim that reads degrade the devices to be appalling.

  • Julie May 3, 2009 10:50 pm

    Time Machine on my Mac does an automatic backup every few hours. I don't have to think about it. Great program.
    Peter: I think the article kick started a great discussion which I have learned from so I appreciate Darren's efforts.

  • Peter May 3, 2009 09:36 pm

    It seems to me that this article is a waste of time as the author is using out of date information.

  • Mike May 3, 2009 09:18 pm

    Hi Everyone,
    I put my cards into a card reader then from there I cut and paste the pics to the computer, I would like to know if copy and paste would be better.
    Regards Mike &TIA

  • Hans May 3, 2009 04:49 pm

    I use the Photo Downloader in PS Elements, then post process when the images are on my Hard Drive.
    However, with todays cards you shouldn't worry too much about life expectancy.
    My Kingston 1 GB cards still work great, but are too small compared to the 4 GB cards I use now.
    I still remember one of my first digital cameras, a Fujifilm Finepix 2800Z with Smartmedia cards.
    The camera lasted longer than the cards, when my last card died, a new SmartMedia card was so rare that a new camera would've been cheaper...

  • Archersdad May 3, 2009 04:38 pm

    The read/write cycle warning is very out of date. For example, Windows Vista has the option of using a memory card for "ReadyBoost" which speeds up hard driave access time and can function as additional RAM. I have been using an 8GB card in this capacity for over a year of nearly 24 hour up-time with no degradation of the card or errors.

  • Victor Augusteo May 3, 2009 02:53 pm

    wow, great tips.

    i personally haven't had any lost of data on memory card yet (and i hope i never had to experience it). but i once lost most of my photos because of virus attack on my harddisk. so i reckon backing up your archive is just as important as saving your photos in memory card to hard drive.

    and yeah, one simple word of advice. you should try to save your photos to the computer when you finished your photoshoot. nobody knows what would happen to your memory card. having your photos in 2-3 places is certainly better than 1. plus it gives you peace of mind :)

  • Sean May 3, 2009 02:01 pm

    @Julie: Really there isn't a finite point in which you should throw out a card. I still have a 256MB card that works perfectly. The only problem with it is that it only hold maybe 8 RAW files on a 12MP camera.

    I did a little more research on these cards and came to find that even the data I posted about 100,000 write cycles is dated.

    It would appear that the current standard for measuring MTBF (Mean Time Before Failures) of CF cards is no longer measured in write cycles, but in continuous hours of use. Apparently the current crop of memory cards are rated at >1 million continuos hours. So it would appear there is no longer any truth at all to even the write cycles being of any significant significance.

    I came upon an Industrial Grade CF Card with a MTBF 4M continuos hours.

    Your card will likely die from the contacts becoming degraded (worn, oxidized etc), a power surge or over-current situation or something else *long* before it dies simply from use.

    It absolutely *wont* wear out simply from leaving the card in the reader as stated in the above article.

  • stephanie beaty May 3, 2009 01:19 pm

    enlightening article and great info. they are durable little things, aren't they? i accidentally washed one of my CF cards in the laundry -- and while it still functions, i never use it for images i would be devastated if i lost.

  • MachineDog May 3, 2009 12:04 pm

    I should mention that in addition to that, hard drives die too, but often due to different reasons because of the mechanics of the drive. I recommend backing up all your photos to another hard drive once a week or maybe once a month, they have software for this that will backup only what's changed or been added instead of moving all of the photos again. This way not only will you have a backup incase the hard drive dies, but it's much you can easily find old photos incase you delete them by accident, and they have certain software that will allow you to back up a new version each time you make changes to it, allowing you to go back in a history much the same way as your history in photoshop.

  • MachineDog May 3, 2009 12:00 pm
    ^^ An excellent program that will retrieve photos from a memory card with a damaged file system or possibly with errors from the life of the card ending, at least you can get most of the pictures off. I recently had a card die and was able to retrieve all but the last photo from it using this program. This will obviously not help with physical damage to the card.

  • Julie May 3, 2009 11:24 am

    I filled a 2 Gb Sandisk card with photos of my kids in Hawaii and then put it through a wash and hot dryer. I am still using that disk 3 years later!!
    I always use a card reader and upload right to Lightroom, remove the card and then save edits to file.
    Thanks for this info.
    Is there a point when you should throw out a card rather than take a chance at losing photos?

  • Michael Leuchtenburg May 3, 2009 11:24 am

    While I generally agree with Sean, I would note that there *is* one way in which an access is like a write: the last access date. FAT32 (and probably FAT16 as well) has a "last access date" field which is updated when a file is accessed. It's only written to if the date has changed, and it is really a date, not a time - it has a one day resolution. So if you leave your card in for many days, it could be getting written to without you noticing, but it's very very unlikely.

  • Peter May 3, 2009 11:00 am

    I personally own a Kingston 32gig SD card that was recently purchsed. I use it on my D90 and it seems to be working great. I appreciated hearing that we should not edit our photographs while in the camera, as I've done it before...

    Great theme to talk about, and thanks for the links for additional information...

  • new media photographer May 3, 2009 09:34 am

    My first cards where IBM Micro Drives. Two 340MB at $500 each. They lasted six months.

    Todays 2GB Flash drive is about $20-30. I've washed them in the washing machine and lost nothing. They still work great. (I'm sure the washing didn't extend their life though)

    Thanks for the info about the Cards I've learned a few things


  • Frank May 3, 2009 09:32 am

    "Bottom line is that most modern cards will become obsolete or fail for other reasons long before they reach their write cycle lifespan"

    If you were to format your card 15 times a day you could hit that 100,000 write cycles cap easy within 20 years LOL.

  • keith May 3, 2009 09:26 am

    thanks for the info about cards & i'll jump ahead to recovery - lots of software out there for recovery i was experimenting just the other day to see what i could recover. art plus has a free one that really works, in fact it worked better after formatting the card.

  • Sean May 3, 2009 09:22 am

    First, I agree whole heartedly with the statement that you should never work on an image that is still on the card.

    However, I do take issue with the statement "Even if the computer is not interfering with the data on the card it still continuously accesses the card. This action is similar to a write cycle..."

    Wrong. The computer is intermittently performing *read* cycles on the card. Unless you are working on photos while still on your card and saving the changes. These are *not* similar to write cycles and do *not* affect the longevity of the card in any meaningful way.

    Modern memory cards have an average lifespan of approximately 100,000 writes per sector, reading the card does pretty much nothing.

    Bottom line is that most modern cards will become obsolete or fail for other reasons long before they reach their write cycle lifespan.

  • wikinoob May 3, 2009 08:58 am

    Even if the computer is not interfering with the data on the card it still continuously accesses the card. This action is similar to a write cycle.
    This "access" without "interfering" would be a "read". But according to wikipedia, reading does not harm the flash memory at all:

  • Ilan May 3, 2009 08:53 am

    "Don’t work on the image while it’s still on the card"
    From painful experience, just decided to bold this sentence :)