Replace CF Cards After Two Years??!!

The CF cards I bought (Sandisk amd Kingston) come with a "life time warranty", which basically means 10 years. In this month's Professional Photographer is an article on image recovery. Quite useful I thought until I got to the "Tips For Minimising Memory Card Problems". Here it recommends to "replace a flash memory card every couple of years" .

I know memory card prices are coming down, but replace cards every couple of years

Claire

That will be just so the average all-around CF card, after many hundreds of loads and unloads will still be proven to say 99% accuracy. Also depends how often you use the cards.. And what sort of conditions.

If I've shot 100,000 shots in 18 months, that's about 1,000 + photo folders, each overwritten each time containing 100 shots in each folder. That's a lot of overwriting.. I wonder how long my Lexar 80x can last.

Hi Wazza,

I'm currently taking 700 to 800 pictures regularly every week, but some of these are indoors with the camera tethered and the image being written to the PC only. But even if all of these were to the CF card, I've got three Extreme III 1Gb cards that I rotate, so over two years that's 83,000 images, but only 27,000ish per card.

I erase my cards by formatting in the camera each time I use them. Will this shorten their life? Is it better to use erase and format less often?

Claire

Makes no difference at all. In both cases it is just the table of contents of the card that is erased.

Well, if you're a pro

1. You can't take chances with losing shots
   
2. You can write off the cost of replacing cards
   
3. You're shooting a lot of photos

I wonder if "they" have stock in the CF company. Or a salesperson working on comission???

If it aint broke dont fix it... I say keep using them as long as they are working!

Formatting in the camera is either better than or the same as erasing, depending on how the camera's firmware works. Since formatting is faster (which is a strong indication that it's also better), I always do it that way.

The issue of flash lifetime is complex; it depends on the file system in use, the way the software works, and the particular chip in the card. However, since all cameras use FAT16 or FAT32, the first variable is eliminated. (Unfortunately, FAT is just about the worst conceivable design for flash!) I'll assume that the software is well designed; there is evidence to support this theory.

That leaves us with the third variable. Oversimplifying, modern flash is limited to between 10 thousand and a million write cycles. Oversimplifying further, a write cycle is roughly equivalent to taking a picture, erasing a single picture, or formatting the card.

Thus, if you're using a low-cycle card, your 27K pictures have already pushed the limit. If you're using a high-cycle one, you're a LONG way from trouble.

I suspect, though I do not know for a fact, that the higher-capactity cards also use more modern technology that can withstand many more cycles. Thus, I think I would worry about shutter lifetime before I'd stress over the card life.

As a side comment, when a card does fail it's almost guaranteed to fail in what another poster called "the table of contents" (which is what the FAT boils down to). That means that recovery software has a good chance of getting your pictures back.

Read up on "wear levelling". Whilst the individual card manufacturers won't reveal what techniques they do or don't use, I think it's highly likely that they're using strategies to defend against every update of the FAT wearing the same area of the flash memory. It is true that FAT is a flash hostile filesystem, but it's what people have standardised on due to pretty much ubiquitous operating system suppport.

Further, I suspect there's some spare blocks available for the card to reallocate, hard disk style. Have you ever noticed how the capacity of a flash card isn't a power of two, when memory chips almost certainly are a power of two (because of the binary addressing used).

David

So far it is a moot point for me as about the time that two year point rolls around I need bigger cards anyway so the old ones don't get used often after that and lately (at about the 4 year mark) given away to family as their value drops below $20 each.

Thanks for the replies everyone... I understand a bit more than when I posted the question.

I'm not a Pro (well not yet anyway) so losing any images wouldn't be a disaster and as gkuenning posted, I guess the recovery software that comes with Sandisk CF cards might get them back.

The one concern I had was that I'd wasted money with the Extreme III cards. I know that my 350D is slower than these cards, but I invested in the marginal cost difference over an Ultra II card in case I upgrade my camera.

I'm just going to keep shooting with them until they show signs of problems.

Claire

Chances are you will replace the cards because of size or new model before they ever get broken.

I know many say don't buy the Extreme III unless you are a pro and save the few dollars and buy ultra II instead. But as you noticed the difference in price is so small that it is more intelligent to buy the better card. I have recently replaced my Ultra II cards with Extreme III cards. Also as Extreme 4 is on the way the price on Extreme III is dropping making the difference even smaller.

Here is my story/experience: http://www.canongraphe​rs.com …ad.php?goto=new​post&t=612

The LEXAR CF is one over year old.

Hi Tommy ,

Hmmm good point about new models...Canon might go over to SD cards or something other than CF, as Nikon has with the D80. My dream camera - the 5D - does take CF, but then 1Gb cards may not be big enough, so as you say the issue will solve itself one way or another.

I really appreciate the help here...

The last Extreme III card I bought was over £12 cheaper than the first one I got only a few months ago.

Claire