Does this corrupt memory cards?

Its also worth knowing that some manufactures offer utilities to low level format cards and other utilities to error check them, i.e perform multiple read writes to check error status, speed and so on. Some formats only remove the basic file table information (hence why recovery is possible) so keep in mind performance can also be effected by not knowing manufactures guidelines for certain cards, take for example new Cfast used in Canons 1DX2, they need occasional formatting with Sandisks optimizer/application to retain maximum performance from the card. In my experience most corruption takes place when data is transferred from the card to the computer, you can also suffer physical card failure such as broken pins or cracked PCB is smaller more fragile cards such as MicroSD/SD and so on, with high speed USB transfer directly from the camera is now fast enough you could remove the risk of taking cards in and out of the camera body.
 
He said that deleting images this way "is the easiest way to corrupt a memory card"


NON SENSE!

To be remembered, each take is a single file; treated as such
written and read as such by the camera file management.

I would possibly think otherwise if takes were recorded as file
libraries… but they are not.

The better way to avoid any problem is to let the camera take
care of your card by re-formating it from time to time.
 
I think formatting the card is preferably done in camera though rather than in/on the computer.

:agree:
Yes, absolutely, let the camera manage the card.
 
Saving an image or deleting use exactly the same method of updating the filesystem directory contents. One operation being more able to 'corrupt' the card than the other is twaddle.
 
Saving an image or deleting use exactly the same method of updating the filesystem directory contents. One operation being more able to 'corrupt' the card than the other is twaddle.

Except that Saving also writes a lot of data to the card, as well as updating the directory information on the card - hence the increase in risk of some form of corruption occurring.
 
Total rubbish!

I've deleted images for decades, in camera, without any problem.

I always format in camera too.
 
To be fair, all writes to the card carry a degree of risk so I just carry an artists pad and a set of charcoals around with me, and draw what I see as I just don't want to take the risk of corrupting my cards no matter how infinitesimally small the risk might me.

Also means I can leave my camera in its hermetically sealed humidity controlled bag, with filter and lens hood on (just to be on the safe side) :)
 
To be fair, all writes to the card carry a degree of risk so I just carry an artists pad and a set of charcoals around with me, and draw what I see as I just don't want to take the risk of corrupting my cards no matter how infinitesimally small the risk might me.

Also means I can leave my camera in its hermetically sealed humidity controlled bag, with filter and lens hood on (just to be on the safe side) :)
Great stuff. You know it makes sense. It's the only way to be sure.
 
i've always done this before, although not habitually or regularly. I've had one corrupted 16gig CF card in all my days touch wood. However, after reading this thread I think I won't be deleting images via the camera again, unless I have a real pressing need to free up a tiny bit of space for a few more shots, which let's face it is unlikely!
 
Been doing it years, I have never had a card failure of any kind.

i think people who run photography courses just like to have something to preach on
 
It's witchcraft.

If you wave your hands about and say some magic words and something happens, then it is obvious that witchcraft works.

Similarly, if you delete an image in camera and a memory card fails, it is obvious that deleting the image has caused it.

Cause and effect.

Unfortunately, it doesn't work that way - and neither does witchcraft.

Wayne's example on page 1 implies that it is the deleting in camera that causes it. It doesn't suggest that maybe there is something wrong with his friend's camera or some other reason.

I'll stick with witchcraft being the reason, it's just as reasonable.
 
To be fair, all writes to the card carry a degree of risk so I just carry an artists pad and a set of charcoals around with me, and draw what I see as I just don't want to take the risk of corrupting my cards no matter how infinitesimally small the risk might me.

Also means I can leave my camera in its hermetically sealed humidity controlled bag, with filter and lens hood on (just to be on the safe side) :)

Does this mean people actually use their cameras? I thought they were only for display and talking about in forums:LOL:
 
It's an old wives' tale. The basic process of using File Allocation Tables has been around for 40 years, and the camera manufacturers have been using them for around 20 years. To suggest that they might not know how to do the programming properly after all this time is just laughable.

It was certainly a problem a while back as people tried various hacks to avoid supporting multiple versions of FAT, or just over-simplified code to save space. I suspect this is where many of the dire warnings stem from, but that was ten??? years ago.
 
This thread has sorted out the pessimists from the optomists
And the scientific from the magic school of photography.

It stands to reason the more you use a card and the more you abuse, it the closer you get to a failure..

But deleting a file is so minor an operation that the chances of a failure occurring at that moment is in practical terms negligible. And impossible to attribute to changing a single digit, amongst multiple millions of 1's and 0's

However failing to write a 0 or a 1 will not corrupt a card anyway.
 
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But deleting a file is so minor an operation that the chances of a failure occurring at that moment is in practical terms negligible. And impossible to attribute to changing a single digit, amongst multiple millions of 1's and 0's

However failing to write a 0 or a 1 will not corrupt a card anyway.

Being that it failing, is probably due to a failing block of transistors, it absolutely can. Flash memory does eventually wear out.
 
Being that it failing, is probably due to a failing block of transistors, it absolutely can. Flash memory does eventually wear out.

Anything can fail. Your car might spontaneously combust, but what are the chances of that? Of all the 1001 things that can go wrong, deleting an image in-camera has got to be bottom of the list. Buy good cards, treat them carefully, don't worry about it.

Yes, cards can wear out, and they can also slow down. But only after a few hundred thousand re-writes, by which time they would have fallen to bits anyway.
 
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Anything can fail. Your car might spontaneously combust, but what are the chances of that? Of all the 1001 things that can go wrong, deleting an image in-camera has got to be bottom of the list. Buy good cards, treat them carefully, don't worry about it.

Yes, cards can wear out, and they can also slow down. But only after a few hundred thousand exposures, by which time they would have fallen to bits anyway.

Completely agree :)
 
I once dropped an olympus XD card and it stopped working. which is the only time a camera card has given up on me.
However I had a Samsung micro-card in my tablet that failed and Samsung replaced it.
I suspect they are more fragile.
 
This is something I wrote some time ago for a magazine article, as a result of my best googling and speaking to card manufacturers. I asked them about deleting in-camera, and about aging - they said no problem. But cards can fail, sometimes for no apparent reason, though there are a few easy and obvious things we can do.

- Buy good quality cards. One of the easiest ways for a manufacturer to bump up their profits is to lower quality control standards.

- There are fakes about and they're very hard to detect, so buy from a dealer that receives stock from an official distributor. Some manufacturers provide a list eg Sandisk https://www.sandisk.co.uk/about/where-to-buy Amazon and My Memory are recommended on-line sellers with good prices.

- Insert the card carefully, don't force it. They are a tight fit to ensure accurate alignment of the contacts.

- When the camera's data-light is on (say after a sequence in continuous shooting mode) do not switch the camera off and don't open the card door. Try not to jolt the camera, which could dislodge good electrical contact.

- When downloading to PC, insert the card carefully and don't jog it during data transfer. Use the 'safely eject media' feature when finished.

- Re-format the card in-camera after each download.

- Store cards safely, keep them clean and protected. Just dropping them in a jeans pocket is not a great idea.
 
Having scanned through this thread, I can't see anyone explaining why your tutor would have said what he said - apart from saying it is good practice / an old wives tale / etc.

So here goes:

SD cards, CF Cards etc are just a form of flash storage which is a development of EEPROM (Electrically Erasable Programable Read Only Memory). Essentially electronic charge is used to set or unset electronic gates which correspond to the bits that form a file. With flash memory, writing and reading of this data is done in pages or blocks (which are a whole chunk of bits) which allows the process to be a lot faster than original EEPROM ever was.

Each gate can only be set & unset a certain number of times - if you look for a manufacturers data sheet this is usually listed as the total number of read/write cycles for a card. After this number of cycles it is likely that the corresponding gate will report the wrong state (1 or 0) - or will simply be stuck at a certain state, hence the corrupted data.

Therefore, all flash based devices will eventually fail, and when your memory card starts to produce corrupted images, throw it in the bin ASAP! The flash HDDs in your computer will usually use TRIM or another such method to spread the data around so that it uses up the 'bits' life expectancy at a even rate. However SSD drives will also eventually fail - it is just hoped that TRIM will mean that the drive lasts as long as the other bits of the computer. Cameras and SD/CF cards are much more simplistic so will fail sooner.

The more you use the card, the quicker it will fail. So the recommendation to only format a card and not 'chimp' and delete images as you go is a good one. You can read a card as many times as you like, it's a read/write cycle that counts. If I write 1000 images to a card and delete 600 of them as I go then I have committed (simplistically) 1600 cycles, however a format will usually only be a few cycles at best (it just recreates the File Allocation Table) so if I write 1000 images then format once I've copied them off then the equivalent number of cycles would be 1001 (not real numbers but gives you a representation). Shot - read off - format is therefore the best method.

So the tutor was right - you should format your card once, not chimp and delete if you want to maximise the life of your card. The advice probably started because when flash memory first arrived the read/write cycles were much lower than they are now, so people probably saw errors more frequently - but just because cards have got better don't think that it will never happen.

As a final happy/sad note - also don't think that flash devices are good for backup, they are not. Unless the data is 'refreshed' at regular intervals (i.e. re-written) eventually the gates will start to lose their charge and the data will corrupt. The best guess is that the data may be good for 5-10 years. So all those wedding couples who have their images delivered on USB (I sent one out last week) will have a bunch of corrupt images if they try and look at their images in 10 years time. This is why wedding albums and prints win on every front.

Hope that's helped separate fact from fiction,
Matt
 
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