Why you should not delete images on your memory card using your camera

Dec 11, 2016

Jeff Cable

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Why you should not delete images on your memory card using your camera

Dec 11, 2016

Jeff Cable

We love it when our readers get in touch with us to share their stories. This article was contributed to DIYP by a member of our community. If you would like to contribute an article, please contact us here.

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As many of you know, I spent many years of my life as Director of Marketing at Lexar dealing with the ins and outs of the memory card business. And in all that time, I have never written a blog about the do’s and don’ts of memory cards. Now that I have left Lexar and not on that side of the business any more, I feel that I can write this objective piece for you without any conflict of interest.

And if you are taking digital photos on a memory card (and you probably are), YOU WILL WANT TO READ THIS!

First, let me explain the memory card in simple terms for you.

Most people look at a memory card as a piece of plastic or metal, and they don’t think much about them. But inside those covers, there is a LOT of intelligence. There is flash memory, a controller and much more. The quality of that memory and controller often determines the speed and quality of your card.

Your memory card has something called a File Allocation Table, otherwise known as a FAT Table. Think of your memory card as a book and the FAT Table as a Table of Contents. When you format a memory card, you are not actually erasing the card, you are just clearing the FAT Table. So…you have removed the Table of Contents, but the chapters of the book still remain. Yep, all the images will remain on your card until you shoot more and overwrite them. This is why you can use a program like Lexar’s Image Rescue, SanDisk’s Rescue Pro or other data recovery software to recover images from a card even after it is formatted.

And now for the tips, which I am going to write in the order of importance:

1. DO NOT erase images from your memory card in your camera! Clarification: What I mean by this is: Do not go through your photos and delete them one by one using your camera. I see people (including professional photographers) doing this all the time and it is a REALLY bad idea. Your camera is awesome at taking photos, but it is not very smart at managing the data on your memory card. Deleting individual images from the card using your camera is a great way to scramble the FAT Table. DON’T DO IT! And heck, memory cards have gotten so inexpensive and large, that you should not have to delete images to save space. Just pop in a new card and keep shooting. Once you have downloaded to your computer, and backed up the images THEN format your card to use it again.

2. Format your memory cards in your camera, not on your computer. I have seen countless web sites which tell people to format their memory cards on your computer. This is just bad information! You want to format the cards in the camera. And you should do this on the camera your are shooting with. I am currently shooting with the Canon 1DX Mark II, Canon 1DX, Canon 5D Mark IV and Canon 5D Mark III, and I format the card in the camera I am using. You are reading this correctly…I do not format in one Canon camera and move it to another. Will they work? Yes, they will. But it could cause issues down the road. Speaking of this, it is not a good idea to pull a memory card out of one camera model and putting it into another without formatting. I have seen people shooting with a Canon camera, pull the card out and start using it in a Nikon camera. They like to be formatted a certain way and each manufacturer does it their own way.

3. Speaking of formatting, it is a good idea to format your cards after each shoot. Once you have downloaded your card and have the images IN MORE THAN MORE PLACE, you should format that card before it’s next use. It keeps things cleaner on the card.


4. Use a good card reader! I can not tell you how many times I have seen professional photographers take a high quality card out of a $10,000 camera and put it into a cheap no-name reader. Ughh, it just kills me. When I was working at Lexar and a customer would call me about a corrupted memory card, one of my first questions I would ask is “What card reader are you using?” Folks, those memory card readers have intelligent controllers inside them, just like the cards! I have seen way more cards corrupted in a reader than in a camera.

5. Don’t fill a card completely. Even though most memory cards are built really well and have all kinds of intelligence in them, it is not a good idea to fill a card completely. One of the reasons that I love shooting with large memory cards, is so that I have tons of head room to shoot a lot of photos and not worry about overfilling the card. FYI, I also have the same mentality with my computer hard drives. I never fill them, because their performance suffers a lot when they are full. I usually fill a hard drive to a maximum of 90% and then start writing to a new one.

6. Don’t pull a memory card out of your camera or card reader when data is being written or read from the card. If data is being transferred to / from the card and that process is interrupted, it is quite possible that you will lose some or all of your photos. And don’t always trust the red light on your camera to determine is data is being transferred. Before I pull my memory cards, I always wait an extra couple of seconds after the red light on the cameras goes off, signifying that the data is done being written to the card.


7. If you have two card slots in your camera, write your images redundantly to both cards to have more peace of mind. This way, if one card gets corrupted, you can most likely get the images off of the other card. I always do this!

8. Purchase name brand memory cards. As you may have guessed, I use Lexar memory cards in all my cameras, but that is not to say that they are the only good company out there. SanDisk makes a good product as well. There are others too, but make sure that you do not use one of those cards made by a no-named company. Remember, you are trusting your images to the card! And you are going to be using the card over and over, so spending a couple of dollars more to get a better product, in the long term, will not cost you much more. Nothing kills me more than seeing someone shooting with a great camera, expensive lens and a crappy memory card. Yep, this gets to me even more than someone using a crappy reader.

And just for fun, here are some common misconceptions about memory cards:

* If memory cards get dropped in water, the data will be lost forever!

This is not true. Because memory cards are made with solid state memory, it is not uncommon for them to go through the washer and dryer and still be useable. Would I keep using that card after a situation like this? Probably not. But most likely your data will still be on the card and can be recovered. I used to jokingly say to people, “If you put your card through the washer, make to put it in the dryer too!”

* You must keep your cards in covers.

I hate to tell you this folks, but I have my cards loose in my bags all the time. I do not use the little jewel cases that come with the cards. I do use the ThinkTank Pixel PocketRockets, but also have countless cards thrown in my bags. This has never been an issue.

* (Added) Going through airport X-Ray machines can damage your cards

I have had many people ask me how they should travel with their memory cards, especially at airports. In the old days, the X-Ray machines could damage 1000 speed film, but they pose no threat to the solid state memory cards you own today.

To sum all this up…

After reading this blog post, I hope you have a better understanding of your memory cards and readers and appreciate them a little more. There is so much technology packed into these devices, but they are so small and unassuming that it is easy to take them for granted.

These are simple tips that could save you from a disastrous situation. I hope that these help all of you to keep your memory cards and images safe now and in the future.

In case you are wondering…here are the cards and readers I am currently using:

About the Author

Jeff is a world renowned, five time Olympic photographer having covered Beijing, Vancouver, London, Sochi and now Rio. He is one of the most sought after presenters and educators in the photography space. You can find out more about Jeff on his website, follow his adventues on his blog, or reach out to him through Facebook. This article was also published here, and shared with permission.

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109 responses to “Why you should not delete images on your memory card using your camera”

  1. Ahmet Avatar

    1.) Why?
    2.) Why?
    3.) Why?
    5.) Why?
    Just to have a better understanding. Other than trust me, I’m a marketing director!

    1. Gregg Bond Avatar
      Gregg Bond

      1) As indicated, cameras are stupid and can nuke the whole card if you get half way through a delete operation and start shooting on it again.
      2) Because then you know it will work in that camera, I’ve had times when cards from one body wont work in another. They are that picky!
      3) That’s more good data practice, than protecting the technology. It’s supposed to say “Once you have downloaded your card and have the images IN MORE THAN ONE PLACE”.
      5) This will ensure you dont make the card work harder at wear-levelling than it needs to, it can write images without fragmenting and having to hunt out a few K of storage here and there.

      1. Fabrice Bacchella Avatar
        Fabrice Bacchella

        Fragmentation is a spinning disk problem. It’s totally pointless on flash.

        1. 'smee Avatar

          pagination is an issue… but has nothing to do with the crapfest in the OP

      2. Ahmet Avatar

        You are repeating the statements, but there is no explanation behind.

    2. Fabrice Bacchella Avatar
      Fabrice Bacchella

      And that’s a good reason to don’t believe him. Marketing guys are not paid to understand what they sell.

    3. Robert Alatalo Avatar
      Robert Alatalo

      1) There is a lot of factual comments and I would say the world won’t end if you do delete pictures from the camera but a lot of things depend on many different aspects. If you have an older or cheaper camera then they may not be using a quality FAT implementation or may have other quality issues and every file operation leaves the potential for corruption. Deletes are file operations which generally don’t need to happen from the camera.

      2) Formatting starts over and if there was any file system corruption before, it’s gone after the format. Why from the camera and not the computer when the computer probably has more options? The reason is the camera may not understand or be able to work with the newer versions, so doing it from your camera means being certain that it is working with a file system that it fully understands.

      3) Formatting is a fresh start, problems which might have lead to corruption are wiped out.

      5) You won’t know you’re at capacity til you take a picture only to find you don’t have enough room to save it. It also means that if you’re shooting an event or such you now have let the card decide when you need to change cards versus finding a quiet time to change cards before it was full.

    4. Jeff Koelpien Avatar
      Jeff Koelpien

      formatting in the computer will blank the card, but formatting in the camera sets up the directory tree and folders where it sends the files. The names of the directories are different for each camera, So if you take a card from one camera to another and it don’t see the directory it wants, it will create it and the previous one is gone.

      I seen plenty of sad stories where people “lose” the computer files, and they already erased the card. (so I recommend them Zero Assumption Recovery) I don’t format until the photos reach their final destination. Another hobby photographer i know NEVER erase their cards, they buy more new ones.

      So I format the cards BEFORE leaving for the job, not throughout the day as I need them, because sooner or later we would format the used card and lose the morning’s photos.

      My one computer uploads the card twice as fast as the other computer with the built in reader, so yes, the reader matters.

  2. MiamiC70 Avatar

    This whole article is complete and utter BS.

    1. WillMondy Avatar

      Prove that it is BS then.
      Would be good to share useful information that could help other photographers.

      1. Fabrice Bacchella Avatar
        Fabrice Bacchella

        A good advice: ignore Jeff advice, you will save time.

      2. BigTurk Avatar

        Part of my proof that at least part of this isn’t true is that I have always deleted pictures on my digital cameras (or any digital device, for that matter) and have never corrupted a memory card. Seems kinda silly to me to say you can’t delete photos via your camera?

        1. Marko Jovanovic Avatar
          Marko Jovanovic

          Deleting files on camera can cause file system fragmentation, and that, in theory, could slow down writing, especially when card is near full, but that probably depends on camera type

          1. Fabrice Bacchella Avatar
            Fabrice Bacchella

            Fragmentation don’t slow down flash disks.

          2. Robert Alatalo Avatar
            Robert Alatalo

            No but re-writes do.

          3. Fabrice Bacchella Avatar
            Fabrice Bacchella

            Small rewrites (less that about 256KiB) are hard for flash. Small IO are hard for every kind of storage. Guess what ? We’re talking about 20MiB operations here. Everything become much more simple in such case. What’s why all pseudo tips of this guy are not better than random noise.

  • mikebartnz Avatar

    Another bright spark that is full of piss and wind. If you have a dispute when anything he has stated say it but don’t be a prat and just call it BS.

  • Snugge Dr. Avatar
    Snugge Dr.

    holy mother of crap, it was a long time since i read an article with so much nonsense… thanks for the laugh jeff!

  • Floyd Davidson Avatar
    Floyd Davidson

    Not all of it is nonsense, just most of it. Note that the guy is a.marketing dweeb! Technical facts are not his area of expertise.

  • keir faulkner Avatar
    keir faulkner

    he missed a lot

  • Sam Dickinson Avatar
    Sam Dickinson

    FAT Table…. kills me… File Allocation Table Table….

    1. Fabrice Bacchella Avatar
      Fabrice Bacchella

      This guy as not the slightest idea of what he is talking about. He thinks that throwing in the air some magic manipulation are good practice, as he as seen the knowledgable guys (the enginner) do and he try to mimic them.

      1. Floris Avatar

        Come on, FAT table is commonly used in every IT environment I’ve been, quite a few. What are you trying to say here?

        1. Fabrice Bacchella Avatar
          Fabrice Bacchella

          That Jeff Cable try to look like a serious guy but is not.

          1. mikebartnz Avatar

            Why don’t you try and dispute anything he has said instead of just being a prat.

    2. Mr. Sean Avatar
      Mr. Sean

      That’s like ‘ATM machine’; Automated Teller Machine machine.

      1. longshadow Avatar

        If ATM is the mnemonic, then machine works well after the mnemonic. Nobody will call it the AT machine. Same with FAT table. I know absolutely no one who refers to the table as just the FAT.

    3. kingnacho Avatar

      Nobody actually calls it the FAT table, Typically you just call it the file system.

      1. Tripper Avatar

        Yes we do. What file system is it? XEOS? Mac? NTFS? NFS? They all have metadata that is used by the filesystem to keep track of where the user data is, called a File Allocation Table. There are two older versions of the file system used by Microsoft called FAT16 and FAT32, one was 16 bit and the other 32, both superseded successive versions of NTFS, the latest being ReFS, which came out with Windows 8 Server.

        1. DERP Avatar

          True. I have conflicts when I forget, going between a Mac and a PC.

        2. Jase1125 Avatar

          Forgot about exFAT

      2. Andycam Avatar

        I was for a long time an electronics engineer, digital flight systems, and this is good advice – BELIEVE ME. It’s not difficult stuff to follow, really. Some of you out there could do with some deeper education before throwing insults around.

      3. longshadow Avatar

        I do when I’m referring to the table itself. The table is PART of the file system.

  • Kambis Avatar

    Please give proofs/references for No. 1 and 2.

  • Stefano Venneri Avatar
    Stefano Venneri

    Format after every shoot? Yes… so you cut its life as every flash memory or solid disk…

  • Chris BSomething Avatar
    Chris BSomething

    This article is old wives tale BS. The FAT file system is the simplest file system known to man and the most well documented and well understood. Deleting a file on FAT is basically a matter of writing one byte in the right place, it’s not complicated. It’s not voodoo.

  • catlett Avatar

    Please cite any credible source for #1 as I have been shooting DSLR for a very long time and been on forums just as long and have never heard of a single instance of this.

    2 is essentially correct.
    3 is patently false as there are limited writes for memory cards.
    4 is likely wrong and a case of confusing circumstance with causality.
    5 is total nonsense.
    6 is correct in that the specific file(s) that are being written from the cache won’t be there but it won’t do anything to files that are already written.
    7 is a personal preference but I would be very curious to see credible citations where this has mattered in the slightest. In other words real times from credible sources when one of the cards had more or different files than the other one did.
    8. Every single memory card I have ever seen is a name brand memory card. They don’t ship them with white labels on them and no name.

    Most of this just sounds like stuff you have dreamed up in your own head and spout it as fact. The idea that you think memory cards act the same way when filled as hard drives tells me you are WAY over confident in your technical knowledge. Ken Rockwell does better research than you do.

    1. Lee Raymond CM Avatar
      Lee Raymond CM

      I’d say 1 is probably a good recommended practice but not for the reasons the writer suggested. I do not delete photos off the camera because:
      1. It’s better to leave battery power for taking photos than doing delete.
      2. Navigation on the camera screen is not very ergonomic: screen size smaller, no complete view, inconvenient buttons all leads to higher user error rate – deleting photos you want/need to keep.
      3. Deleting on the camera, especially right after you take them, means that it’s not backed up. The deleted photo may not be perfect but it may be the best you could do in that shoot.

      Messing up the FAT is bad but I trust that most modern camera can handle it very well nowadays.

      1. catlett Avatar

        I agree with your logic and don’t generally delete in camera because the camera screen is an inefficient review mechanism. When I am shooting I generally don’t have the time or inclination to even look at what I have shot other than a quick histogram exam to make sure there isn’t something wacky in the exposures.

        There are also times that even failed photos are of some value for composites or whatever. The author trying to give strong advice on what his instincts tell him rather than demonstrated fact is what I protest.

    2. BrendonF Avatar

      Actually #4 is very likely true. I used a good card reader for a long time with no trouble. When that failed I got a cheap one and after a few days one of my cards got corrupted. I formatted the card and kept using it and some time later another card got corrupted and I had to format that one too.

      I got rid of the card reader(it worked fine except for the corruption issues). I got a Lexar USB 3.0 card reader and touch wood 1 year later no memory card issues so far.

      1. catlett Avatar

        Here’s the thing … “Use a good card reader!” well yea. Use a good toothbrush. Use a good deodorant. Use a good everything. One can’t tell by name or price if it is good or not. There can be flaws or quality control problems with any company. So yea, 4 is likely true but really he didn’t say anything in the end.

      2. guestymcmorphmuffin Avatar

        Same experience. My cheap card reader corrupted 3 cards in a week! I didn’t make the connection until the third card as one of the 3 was an older card (8gb). NO problems since buying a new reader.

    3. Brandon Evans Avatar
      Brandon Evans

      8. Yes they do. One word: “eBay” or “Amazon” or “China”
      Pick your favorite.
      Here’s a few dozen to see with your own eyes: https://www.amazon.com/Micro-SD-Cards-Generic-Memory/s?ie=UTF8&page=1&rh=n%3A3015433011%2Cp_4%3AGeneric

  • Pablo GeekFace Canning Avatar
    Pablo GeekFace Canning

    This article is a load of rubbish. The guy doesn’t include a single source of evidence for any of his arguments.

    1. Pete Brown Avatar
      Pete Brown

      He starts on the right path then just goes off on one

  • Jarek Niskiewicz Avatar
    Jarek Niskiewicz

    Not to delete images on camera cause it can corrupt files?! Lol sure…

    1. Arend. Avatar

      after each delete the FAT needs to be updated, which can cause it to become corrupted. Not a big chance, but still. Still think it would be better to tag bad photo’s so you don’t have to delete them (maybe this bad photo was a once in a lifetime photo) but you can then easily filter before import

  • Danny Madison Avatar
    Danny Madison

    Literally the only factual thing he said in this whole article was
    “Don’t pull a memory card out of your camera or card reader when data is being written or read”

    The rest it utter crap at worst, or possibly true SOMETIMES.

    1. Jeff Cable Avatar
      Jeff Cable

      I guess my 12 years in the industry gives me no credible background, huh?

      1. Ahmet Avatar

        No, it does not give you credibility. I’m in the chemical industry eg. I won’t give you advice on any chemistry related issue, since, I’m 8000 km away from the rearest plant. Being in the industry does not make you expert. You might be, but the two is not related. Don’t get angry, but being a marketig manager puts you even further from the “expert on memory cards” category. Again, you can be, but we won’t beleive it coz you said so. We – clients/consumers/buyers – have this thing. We don’t beleive anything coming from marketing. Sorry. You should know it.

        1. Kaouthia Avatar

          You realise that Jeff is also a client/consumer/buyer, too, right? :)

          1. Fabrice Bacchella Avatar
            Fabrice Bacchella

            Like everyone else then, and I don’t ask advice on a random user at the local shop just because he buys stuff from 12 years.

  • Serge Victor Avatar
    Serge Victor

    Even formatting doesn’t delete files, so it’s just cosmetic operation.

    1. Danny Madison Avatar
      Danny Madison

      Yeah lol, like the guy doesn’t even seem to realise that Low Level Format is a specific option on most cameras to properly overwrite the card data.

  • JBR Avatar

    Well… I trust Jeff Cable. I have followed his blog for a long time and he has always been a straight shooter and a “good guy.” Can’t we disagree without being so harsh? State your opinions, objections, etc., but everyone is entitled to their opinion. In general, the “we” is smarter than the “me” and I like learning as much as I can from everyone. I am thankful when people are willing to share their experiences and expertise, but I do think we should have some decorum.

    1. Jeff Cable Avatar
      Jeff Cable

      Thank you.

    2. DERP Avatar

      “entitlement” is how people get bad advice

  • ikillflesh Avatar

    You guys are haters. DIY photogs are tools.

  • Roman Alurkoff Avatar
    Roman Alurkoff

    Every time I have gap in a photoshoot, I chimp and delete. Saves me heaps of time on import, conversion and building previews.

    1. Paolo Avatar

      Agree! And stating this marketing BS: “And heck, memory cards have gotten so inexpensive and large, that you should not have to delete images to save space.” While showing pictures of 450 euro memory cards… Like we are all super rich?

  • Simon Horne Avatar
    Simon Horne

    No problem not right at all. Deleting in camra or through a reader is just the same as deleting a file on any hard drive it’s. Hoighly compressed and still there and recoverable but you can clear a drive totally by formatting it depends on the typ of format you do. Some are not that deeper a format others clean everything. It is better to do a deeper type format for a few reasons

    1. Arend. Avatar

      actually, doing a deep format on flash memory is a bad idea due to the limited write cycles of flash. It is only needed if you want to make sure nobody can scan your card for old photos (but even a deep format won’t help you there, use special software for that. Deep format writes 0-s, after which some experts can still find information (CSI type people :-)). If you write true random data to the memory this gets harder (but further limits the lifespan of the card)

  • aleixandrus Avatar

    by not erasing photo by photo, are u considering the number of usage cycles or are there other factors? Where evidences are?

  • 'smee Avatar

    The only real info here is the following:
    1. don’t remove a card that’s in use (reading or writing)
    2. deleting files individually can cause a lot more effective writes cycles to your card DUE TO PAGING (and those are limited).
    3. cheap cards may have more data issues than expensive cards – but that’s a QA issue more than anything else. Buy quality, but don’t get hung up on ‘name brand only’.

    Other than those, ignore the rest of the BS.

    Formatting is… formatting. It follows an ISO standard, so is not “special to the camera”. The firmware is mostly unique, but even then they are all using the same basic FAT stack that’s been in use for decades. Formatting after every shoot? only if you are ‘clearing’ the card. IF you have room for another shoot, then don’t subject your card to yet more unnecessary write cycles by formatting it when you don’t need to.

    Readers are… readers. A cheap reader may not last very long, but it reads just as effectively as a ‘high price branded’ reader. (they probably both use exactly the same stock parts from China, too).

    Putting your card through the dryer WILL likely destroy any data on it. Your card will probably still work (after formatting) but solid state electronics do not like the high humidity (beginning of cycle) AND high-static (end of cycle) environment of a clothes dryer.

    (FYI. My background is technology: CS degree and over thirty years in the IT industry)

    1. Arend. Avatar

      FAT is by no means an ISO standard, it is owned by microsoft (and they make money each time it is used in a device). It is just the most widely used and therefore generic file system available.

      Card readers do differ. In my PC, i get roughly 1/4 of the speed that my notebook gets, because it uses better (newer) electronics.

      1. 'smee Avatar

        Sorry for being less than 100% complete! Three little points for clarity.

        (1) You have a reader with newer, faster chips. Great. Note I mentioned only the equivalence of branded’ and ‘non branded’ since they would use the same chipsets FOR ANY GIVEN GENERATION. I didn’t say there was only ONE possible chipset. (Moore’s law, anyone?) I have devices spanning many generations sitting on my desk. Unsurprisingly, the newest are also generally the fastest and have the lowest power consumption. That nuance, while true, does nothing to add to or detract from the point made (brand and non-brand IN A GIVEN GENERATION will likely use the same chipsets)

        (2) My bad… I said ISO when I should have said DCF – but we ARE talking about cameras, so….


        (3) Microsoft’s patents on FAT relate only to the “long filename” variants (VFAT), and are generally only enforceable in the US (the key patent was invalidated in Germany in 2013). They don’t get royalties for every device… Many devices/implementations use Open Source alternatives that don’t rely on Microsoft stacks to deliver FAT compliant access and which do not infringe on their limited patents (despite MS’s attempts to bully some folks into paying licences: Motorola & Android being some recent examples). In my opinion: The USPTO ruling that VFAT was “Novel and Non-Obvious” was news to every CS student and professional, since the same techniques had been used in pretty much every file management toolkit since files stopped being linear! But I suppose lawyers were able to argue otherwise.

    2. Nuup Avatar

      Normal formatting will not overwrite each sector but just clear the FAT, marking the sectors as clean. That’s why you can restore deleted files, but only when you haven’t wrote new data on them. Or formatting a larger card/hard drive will not take longer time than formatting a smaller card/drive. But you can select to overwrite each sector with 0 and it will take a significant amount of time more to format, but it’s not enabled by default. Thus, instead of deleting all files, you can just format it and would not induce more write cycles. The controller in the SD card will take care of balancing write cycles to all sectors equally.

      In that regard, a “higher quality” SD card can be better in dealing with these write cycle issues.

  • Andrea Elva Mulder Avatar
    Andrea Elva Mulder

    Rather format than delete

  • kingnacho Avatar

    While the main point about #1 is true, the reason given isn’t really the reason why it is a bad idea. It doesn’t mess with the File Allocation Table or File System, those are part of the software, the delete operation is handled by the FAT/File System. The real reason you don’t do this comes down the physical nature of flash memory. Flash memory has a finite number of writes, a delete operation performs an additional write to where the image was to clear that data from the card. It won’t mess up the File System. Formatting the card doesn’t go through and clear out the data from the card, it rebuilds the File System so there are no pointers to the old images. As you take more pictures the images are overwritten with the new ones.

    1. Robert Alatalo Avatar
      Robert Alatalo

      Deleting images only removes the entry from the directory entry and clears the FAT entries which contained the pointer to the file, marking the space free. It does less damage than the format which you correctly described. The limited writes do come into play but with load balancers it’s not likely a major issue. There are standards describing the file system but there could also be mistakes in the implementations so I would say his list tries to minimize conflicts in implementations but as most implementations are likely good enough, it’s probably not an issue either.

  • Heather5252 Avatar

    This is essentially exactly the same information I was told in photography school. Very surprised people are arguing with it.

    1. Fabrice Bacchella Avatar
      Fabrice Bacchella

      Because it’s old lore transmitted between photographers that don’t know how flash and file systems works. It all make IT people laugh.

      1. Arend. Avatar

        no it doesn’t :-)

        1. 'smee Avatar

          um. yes. it does.

          1. Arend. Avatar

            Not ALL, i know IT for 30 years, it didn’t make me laugh at all!

  • Rick Avatar

    Truly it all comes down to the camera being used and how much the camera pushes the performance capabilities of the cards. These steps have been touted on the GoPro forums for years. Those that followed them went relatively trouble free, those that didn’t bitched and moaned constantly and always blamed the camera rather than following simple card management techniques. And the main reason cards were having difficulty was insufficient data rates. It took the card industry about 8 months to fully catch up to data rates the Hero3 demanded when it was introduced and during that period those that followed the rules did okay, those who didn’t, didn’t. The Hero2 had similar problems.

    So for all the DSLR users who claim the suggestions above must be bogus because you have never had a problem I would have to ask when was the last time you fully stressed the capabilities of your card and did it for extended periods of time? umm… never? Just because it hasn’t happened to you doesn’t mean the issues aren’t real.

    1. Kaouthia Avatar

      Exactly. None of the things Jeff suggested are harmful to *any* camera. But the things he’s saying to avoid doing will prevent disappointment for quite a few cameras out there.

  • Arend. Avatar

    Why are people on this site so negative???
    I think that most of what is said makes perfect sense, i will detail #5 and #6

    SDcards have something call wear levelling in them. This means that if you write to adress 0, it will not Always map to physical location 0, the card will do some math to see if location 0 has been written too many times and map it to another physical location if needed. This means that if you do not fill up your card 100%, it can have a sligtly longer life span. Although you shouldn’t be afraid that the card will fail for that reason, it will take years of normal operation before you get close to the write limit if modern SD cards.I talso coild be (not sure) that formatting the card will allow the sd card wear levelling logic to be more effective.
    then on to #6, it is not only picture data that is written to the card. If you pull it at the time the card rewrites the FAT, you can loose the pointers to your photo’s. It is quite easy to scan the card to find all your photo’s, but filenames will be lost, which can cause some headaches. Also, SD cards use a small RAM cache before actually writing to the flash memory, memory can only be written a block at a time, and the card waits if that block is going to be altered within a short time span before actually updating the flash memory. This is why you sould wait a second or so after the camera says that it is finished writing.

    Just my two cents

    1. Dave_TX Avatar

      You can use your camera and your card a lot but the write cycle lifetime of the card is much longer than your life time with that sort of usage. On the other hand, if you try to use an SD or Compact Flash card like a disk drive you can easily exceed the write cycle limits of the card and it will start to fail.

  • cfw Avatar

    Folks, this is not the New York Times! Take everything here with two grains of salt, and independently look into anything that is important to you or upon which you might act.

  • jimspc Avatar

    Jeff. Possibly one of the better articles on camera cards. I use exactly the same methods as you.
    One thing a card getting wet should have no effect on the card. But it must not be used until it is completely dry. It would seem that many commenters here are not far off losing data the way I read the comments some have written. Also I use only Lexar and Toshiba cards.

  • YoBuddy Avatar

    Thank you! For novice like me this was a great help. ;-)

    1. Rod Pascoe Avatar
      Rod Pascoe

      Most of it is complete rubbish.

  • JPM Avatar

    Thanks for this very informative article! One question: is it ok to use the built-in card reader on a computer (I have an HP) to upload your photos from a memory card?

  • Floyd Davidson Avatar
    Floyd Davidson

    Interesting how the article is being viewed. Items 1, 2 and 3 suggest the author is technically clueless, as all three are the BS that everyone is referring to. The rest of the article is fairly good and provides accurate information, but many are totally ignoring that after seeing how the article starts.

    The author should learn more about the technology before trying to write technical articles for public consumption.

  • JohnFerman Avatar

    Last I read the only SD companies that make their own chips are Lexar, Samsung, Sandisk, and Toshiba. Is this still true?

  • JustAnAubie Avatar

    I use Lexar cards all the time. Just a side note but they’re super cheap at Big Lots. The only time I ever had one fail was in the photo machine at Walmart. And, on more than one occasion, I’ve found a loose SD card in the washer. And it still worked like a charm.

  • Jase1125 Avatar

    As a 20 yr Microsoft veteran, I can tell you his comments about scrambling the FAT table is complete garbage. Not even remotely accurate.

  • Daryl L. Hunter Avatar
    Daryl L. Hunter

    Glad to see I was doing most of this already :)

  • Guido Karp Avatar
    Guido Karp

    I am a professional music photographer for almost 40 years, have celebrated my 5000th concert last year, my 1000th CD cover years ago. I do not see how any of the above could harm – and consequently I fail to understand the rather un-charming comments, especially when all they say is “this is BS”. Help me: how do you help with this? If you have something relevant to say – please do. But mere insults like “…This whole article is complete and utter BS….” or “…holy mother of crap, it was a long time since i read an article with so much nonsense…” – just to quote the first two – do not add any information for the interested reader.

    Guys, Jeff spent a significant amount of his time to write this. While I understand and appreciate you do not agreeing, be sensible enough to add something of relevance. Insults leads to…. check out Jonathan Pie where insults lead to ;-) https://www.youtube.com/watch?v=GLG9g7BcjKs&t=129s

  • Isca Home Avatar
    Isca Home

    This poor guy – Jeff Cable is trying to give some good advice and for some unknown reason people seem to want to attack and debunk him. They even get at him for using common terms such as FAT table which is just a common acronym. They all seem to know better about something or other he says but in essence he is totally correct in all he says even the frivolous stuff. Wind your necks in and be happy someone is trying to help you – even if you may not agree with his advice he is largely correct.

  • Tom Freda Avatar
    Tom Freda

    Having used multiple generations of various types of flash memory cards over 25 years (including PCMCIA I & II, CF I & II, MicroDrive, MMC, Memory Stick, XD, XQD and every kind of SD), I’ve encountered all of the problems the author writes about except #1, which is likely true, but since I rarely delete, I’ve never had a problem.

    So, from my personal experience, I’d say the guy knows what he’s talking about and it’s all good advice.

  • keir faulkner Avatar
    keir faulkner

    When you buy a branded make do so via a reputeable dealer, If you cjoose to use ebay, amazon or gumtree if you wish but take great care, I bought a fuji card this way and it was trash, and do not sell your card to any one. NB:- I use a well known local high street supermarket.

  • Sean Avatar

    Total BS.

  • Eric Moore Avatar
    Eric Moore

    One other tip. Buy your cards from a reputable retailer. SanDisk figures that 1/3 of the cards branded with a SanDisk logo are counterfeit. Of note, Amazon third-party sellers are known to sell fake cards so Amazon is not safe. eBay is definitely not safe. I once listed a camera for sale on eBay with a SanDisk card. My listing was flagged for having a counterfeit card and taken down until I took out the image of the card.

  • Pavel L Avatar
    Pavel L

    Speaking as a electronics repair technician, that’s great info, and I
    agree with it all. The people that say BS, it hasn’t happened to them,
    sure, but someone can also drive recklessly all their life and not get
    in an accident, but it just means it hasn’t happened, but it can, or
    just in denial that it’s the cause. But I don’t totally agree with the
    advice about not bothering to use the protective cases for the cards.
    He says he has them loose in his bag all the time. Yes they probably will be fine from static,
    but there’s also potential crushing hazards, as well as contaminants to the card terminals like
    dust, dirt etc.. Yes if you keep your bag clean, and careful moving things it will help alot,
    but there’s lint etc. that can get on it, and hitch-hike into your card slot in the camera.
    Oils from your fingers on the terminals are also not a good idea, so don’t grab it by the terminal end. And if you don’t use the cases, at least blow them off before inserting.

  • Donald W Nelson Avatar
    Donald W Nelson

    Don’t trust the camera to correctly delete a file, trust ONLY the camera to format a card?

  • Screamin Avatar

    I have a question concerning memory cards. I use Lexar 633X Professional 64GB SD cards. I use the card reader built into my desktop (Dell Studio XPS). One day the cards are reading fine. the next day the computer says I need to format the cards before I can use the. I downloaded the images to anothr desktop, formatted the cards in the camera & the computer stills says they need to be formatted. That’s if the computer evens sees that drive in Lightroom….Help !

  • Richard Crowe Avatar
    Richard Crowe

    I have been shooting digital using CF cards for well over ten years and have never had a CF card which was originally working well, go bad. I did have two separate Kingston cards which were bad when I received them.
    I have been using Lexar CF cards in my 7D and 5D2 cameras and love them. I use a Lexar USD 3.0 card reader and download my images from the CF card to my computer using Adobe Bridge.

  • Jeanne Silliman Avatar
    Jeanne Silliman

    Question: is it ok to put your card directly into the card slot on your computer. I have an iMAC.

  • Quentin Jones Avatar
    Quentin Jones

    All sound advice

  • bart4u Avatar

    One of my Lexar 64GB 1066x UDMA 7 cards could not be recognized by my Pro Lexar card reader a few weeks ago. This card was was used only 4 months. Called Lexar and they said they could do nothing. I took it to a lab here in LA that was recommended for image recovery. They said they could recover the images for $1200.00. They talked about taking the card apart and re soldering part of the inside. Lexar has stopped producing card and their customer support was extremely rude to me. I have about $4000.00 worth of both CF and SD cards. Kind of sucks I picked Lexar as my card company.

  • amrit Avatar

    what happies when you put the camra membory card in grass ??

  • amrit Avatar

    what happins when you hide the camra mebery card somewhere you can not find it and
    then when you find it you put it in the trash??

  • amrit Avatar

    and what happins when the battery is dead and use it and it can not charge and then you put it
    trash and you think it was useful but now it is not useful???

  • Adwb Avatar

    Seems odd that formatting in any Pentax allows you to recover data with appropriate software but format in any Sony full frame and you can’t recover anything , and that’s a fact

  • Ricardo Aragão Avatar
    Ricardo Aragão

    Just writing to let you know that time spent reading this whole text was very worth it. Thank so much for sharing your knowledge with everyone!