Preventing Camera Card, Blu Ray, DVD, CD and USB Corruption

Hands up everyone who has experienced a problem with a computer - yes my hand is up too! How many people have experienced the dreaded "blue screen of death" or a floppy not working or a CD skipping or a hard drive failure or even just a straight power cut and losing their work? Now you will note that I am using long established technology as examples, so what about "newer" technology? The simple answer is there is no difference. Blu Ray disks fail just as easily as CD's and so do DVD's. Floppy disk failure to hard drive failure to solid state drive failure are all possible with the only difference being they fail in different ways but are more catastrophic due to the amount of information they can hold - newer tech holds a lot more information and so you can lose more if something breaks. Camera cards and USB sticks are no different - in fact they are virtually identical in construction. All solid state media has a chip for storing the data and one that "talks" to the camera / computer when accessing it. So what can be done to prevent corruption?


Well the most obvious and most patronising statement is to "back up your data", but just what exactly is a backup? Is a backup copying your photos from your camera card to your computer? Or is it copying your photos to disk? What about compatibility and lifespan? I mean I could have copied my photos to an Iomega Zip drive which was perfectly acceptable ten years ago but not now. Who still uses Zip drives? Or Syquest drives (yuk). Worse still this format war is getting worse - remember HD DVD? Yep RIP HD DVD as Blu Ray won that war - how old was that format before it died? Best to make sure that you move all that important data off those disks while you still can - I mean wax cylinders were once used to store music. Don't see many of those these days.

The simple answer is to go with the flow. CD and DVD are the most cost effective ways of storing data reliably at the minute. Given the fact that CD has been around for a long time and DVD is universally accepted they both get my vote. The jury is still out for Blu Ray at the minute. I know they hold more data but the cost of the disks is prohibitive (at the minute) and also I learned my lesson about being first in line with data storage a long time ago! Too many gigs of data down the pan if one of those babies gets a bad scratch....

“USB! USB! USB!” you all chant - yes, a great storage media. Fancy keychain this, cool necklace that and I hear you can even buy a well known sports car manufacturer’s USB stick as well. Wonderful! A pity then that they can suffer from virus attacks (Sports car backed or not). “A virus? How?” Autoplay in Windows is the single biggest stupid idea that Microsoft (and Apple) ever thought of. “Hmm, let's make things easy for inexperienced users to access data in a very user friendly way and at the same time allow easy exploitation by unscrupulous people to run malicious programs.” It's the equivalent of leaving the key under the mat for people who are unable to carry a set of keys with them, and then they wonder why they get burgled. Turn off autoplay - you'll thank me for it when you have an infected USB stick and it didn't infect your computer but completely trashed your friends P.C. when you tried to give them your latest must have "data". Phew, that was close, shame about their P.C. Not to worry though, eh! Your computer is safe. This is the single biggest downfall for solid state memory. As it can be written to exactly like a hard disk it means that it can be corrupted quite easily. Camera cards and USB sticks are all prone to virus attack. That said, they are the most useful medium for moving data around easily - just not for long term backups. "But they are so flexible!" everyone exclaims. Yes they are. I regularly use USB memory for moving data and they are easily and readily acceptable for supplying files to people. They're a fantastic short term media for storing and moving things. Just not ideal for long term storage. CD's and DVD's on the other hand are.

Apathy. ZZZZZZZZZZZZZZZZZzzzzzzzzzzzzzzzzzzz. Yes the ability to convince yourself that everyone else's computer fails but somehow your computer was made using titanium chips and you are never going to do anything stupid that would possibly affect the way in which it runs. In fact your camera card is made from solid diamond and you are the cleverest person in the world. Hmmm, and then you woke up! Apathy is the single biggest problem with all backups - I do it myself. Too busy, too busy, oh another viral email to look at, cool! Look folks, you have to back up your data to disk. It is time consuming and very, very, very boring to do but remember the gremlins will join forces with the pixies and have a party with your data, completely trashing it in the process unless you do a back up!

Okay, I have made my point. So just how do I minimise the risks? Well there a lot of don'ts. Here are just some of them:

1) Yanking the USB stick / camera card out of the computer before it has finished writing to it. "Come on, hurry up. The T.V. program is starting and I want to watch that rather than a virtual piece of paper flying over a computer monitor." Yep, you guessed it's the number one stupid reason for losing all your data on both the USB cards or camera cards. Patience is a virtue and all that. In the early days there was write behind cache which meant that the computer would appear to have finished writing to the card well before it actually had. It was designed to free up the computer so that you could get on with work while it still wrote the data to the card / USB. The trouble was it was just too easy to pull the thing out of the computer before it finished doing the write. Now a days this doesn't exist but you can still harm the USB stick / camera card by doing this. Always use "safely remove hardware" to eject the card first.

2) Camera battery failure. "Okay I'm going to push this little baby to the limit. Let's stick a slow speed camera card in the camera and take a lot of photos in quick succession using flash on an almost empty battery. Yeah, let's live life on the edge." Then the battery fails in the middle of writing a photo to the card and a whole bunch of "Oh NO's” (or worse) start to happen. Do not use a camera on an empty battery - you are asking for it. Okay here comes the science bit - When you take a picture the camera looks for the nearest available space, writes to it and then updates the table of contents (TOC) on the card. If it fails half way through updating the TOC due to battery failure then your whole card is corrupt. Updating the TOC can take some time if you have a lot of information on the camera card.

3) Formatting the card. "I'm on holiday - lots of time to fiddle with things, let’s get to grips with this new camera. I wonder what format does?" Or, "I've just copied all these photos over, lets save some money by not buying another expensive card and re-use the one we have. Format card, yes do it, now where did those wedding photos go on my computer?" You get the picture (excuse the pun). Always back up your photos to CD / DVD. Then check they are backed up. And when I say check, don't look at the thumbnails - they can look perfectly fine and still have a corrupted photo. Open them up from the disk. Then, if you must, format the card. If you do accidentally format the card then STOP USING IT. You can usually get the photos back, but not if you then continue to take pictures after doing this. There is plenty of software out there to help.

4) Using the wrong size of card or speed rating of card. Look, the one thing that is certain about technology is that it is always getting faster and bigger but occupying the same space. Older cameras may not understand newer cards. If you put a card in your camera that is way bigger than the camera manual is quoting then you may run into problems. If the camera thinks the card is full but is constantly getting a "no I'm not full" signal it may start over writing existing data if it doesn't understand how to access data beyond a certain size. Likewise sticking a really slow card in your camera and then trying to use burst mode on the camera isn't a good idea....

5) Physically damaging the card. Stupid is as stupid does.... If you and your mates decide that some cool shots in the pool is a great idea and you take your precious camera into the pool to take some pictures then don't be surprised if it all ends in tears. If you are super jammy, mega lucky person then you might find that a quick wipe down of the camera and lens is all that is required. If you are just lucky then you might find that the camera has given up the ghost but the card is okay and if you are just like the rest of us then you will find that the card is corrupt. “Okay, it happened, now what?” Well first things first don't make a bad situation worse. Do not switch on the camera. The most important thing is to preserve the photos on the card. So wipe the card down, wrap it up in some tissue paper and leave it to dry in a warm place overnight. Next put the card into a computer using a card reader - if you are the semi lucky type you might be able to read the card. If not try another reader, and another. If it still fails, try drying it some more and repeat. Did I mention you really ought to backup your photos regularly onto CD / DVD? Oh well..... Squashing the card is another favourite: "I know lets put this really sensitive camera card in my back pocket and sit down on it. I'm sure it will be fine." Well folks, no! To understand you have to be aware of what is inside of the card - usually two chips. One for memory and one for communication between the memory and the camera / computer. Considering these chips are thin anyway they are easily cracked but the real weak spot is the pins that they are soldered onto the bread board. They are thin, spindly and don't have any strength in them. So, if you decide to sit on one then you are effectively crushing a piece of silicon between your butt cheeks and the bread board bending and snapping all those lovely spindly pins in the process. Mmmm, lovely. Lots of short circuits there and it cannot be repaired. Did I mention you should always keep unused camera cards in the cases that they came with?


6) Okay what about CD's then? "I did what you said and copied all my photos to CD / DVD and now the disk won't read". Yes, this happens. Well first things first, keep all CD's and DVD's in the cases that they came with otherwise they will get scratched. Before trying any of the following solutions try the disk in lots of other drives – some work better than others, especially a Blu Ray drive which has a much finer laser. In the event of a scratch on the surface then you can get the data back with some elbow grease and some Brasso / toothpaste (no – not the minty blue kind, the white abrasive kind). Yes you read correct – shallow scratches can be removed by rubbing gently from the centre of the disk to the edge of the disk with a mild abrasive. DO NOT GO ROUND AND ROUND when trying to fix scratches on a disk as you are going in the same direction as the tracks on the disk and can make it even worse. If you still cannot read the disk then try some software to extract what it can. CD Roller, ISO Buster, DVD Data Rescue all spring to mind. Another trick is to try and apply some heat to the disk (D.J. trick). Skipping CD? Hold it over a hot light for a while and then try again. The theory is it partially melts the surface preventing a sharp scratch deflecting the laser making it readable again.

7) Mini DVD’s. This is a terrible format. Just don’t use it – there are far better storage media out there. Mini DVD’s were supposedly a great way to record video straight onto the disk and then whack it straight into your DVD player for instant playback and unless you are not normal then it will work perfectly. The trouble is a cheaply made camcorder using this format is trying to write to a spinning disk using batteries to power this which will run out quicker than you can say “unreadable”. As you wave the camcorder around the laser is trying to accurately hit the surface of the disk and record your video at the same time. Invariably it doesn’t. Add to this the simple fact that it has to keep the session open as it has no idea how much footage you would like to add before finalising the disk then it won’t read in the DVD player until it is finalised. If you cannot read a mini DVD then you probably have not finalised it. Did I mention that all camcorders do this differently and there is no universal way to close the disk? This means that if your camcorder stops working and you cannot buy a model identical to the one that is broken then you cannot close the session which means it is unreadable. Stupid system! Finalise all disks after you have finished using them and copy the data off onto a regular DVD straight away. If you are having problems reading them then CD Roller might be able to recover the data.

8) Memory. No, not your memory or the computer memory - plastic memory. This is debatable but the theory goes like this: When you burn a CD / DVD / Blu Ray disk a laser momentarily switches on and burns a hole in the disk as it spins round. This creates the ones and zeros on the disk. Some people argue that as the disks are spinning so fast that the laser makes a shallow hole. Then over time plastic memory starts to take place and the hole becomes more shallow. i.e. if you take a plastic mould and heat it up it returns to its previous shape. The same applies to your burned CD’s, DVD’s and Blu Ray disks. Over time the holes made by the laser start to become more shallow until they become less distinctive from non-holes. When this happens the disk is unreadable and it will fail. Regardless of whether you believe this or not the easiest solution is to copy the disk every so many years and prevent this from happening. This does not apply to commercially made disks as they are not burned into the disk. Personally I think you would only see this happening after many decades by which time CD, DVD and Blu Ray will be completely obsolete and all your data will be on a new format.

So some common sense: Your data is valuable so back it up onto CD or DVD. Make copies and store them in different locations. That way you ensure it will be preserved from even natures most deadly disasters.