If you’re anything like me, you’ve got stacks of old media cards lying around. Be they SD or CompactFlash, these cards in my camera cabinet range in size from 1GB to 256GB, with vintages from 2006 to just last week. The smaller the card, generally speaking, the older it is. Every once in a while, depending on what I’m shooting, I might grab one of those old 8GB, 4GB or even 1GB cards, particularly if I’m just shooting a handful of pictures. A short portrait session, for instance, might fit nicely on a 1GB card—even though I’m shooting 22-megapixel RAW files.
This practice, generally speaking, is not a good idea. And recently, it burned me: one of those files I shot on an aging card was corrupt.
The problem with old media, even flash media which has no moving parts, is that it does have a lifespan. Media cards do wear out. Who knows how many tens of thousands of read/write cycles have occurred on my oldest cards. Better still, who knows what sort of abuses they’ve been subjected to, banging around there in the bottom of a camera case, or tumbling around a desk drawer or, even worse, getting stuffed into a pants pocket. Flash media is not indestructible, and over time, it can become physically worn out as well.
My corrupt file wasn’t that big of a deal; it was just one image of a couple dozen that didn’t have too much variation. But what if that file had been my one-in-a-million shot? Trusting it to an old and tired CF card is not a great idea.
So if you’d like to prevent corrupt image files, here’s my advice for treating your flash media cards with the respect they deserve.
1. First and foremost, get rid of those ancient cards. Media is so inexpensive these days, there’s no excuse for making the same mistake I did and relying on a decade-old card that could be replaced ten times over for a buck per gig.
2. Do not eject a card, from the camera or the computer, while it’s working. Ejecting a card from the camera while it’s still writing data—typically indicated by a bright light adjacent to the card slot, or even by a message on the camera’s LCD—is a surefire recipe for unrecoverable file damage. Ejecting a card from the computer while it’s in the middle of a download, or even prior to unmounting the card, is also a good way to ruin your day. The best-case scenario would be if only the file structure of the media was damaged, rather than the contents of the files themselves. That’s because a corrupted file structure can be worked around via disk rescue software (which I’ve written about in the past in this very column). But an incomplete file is unrecoverable. Once it’s damaged, it’s done.
3. Be gentle with your media. I don’t mean you have to cradle your SD and CF cards on a gilded pillow, but maybe don’t do what many photographers have a bad habit of doing—throwing the cards uncovered into a pocket to bang around with whatever else might be in there. At the very least, use the little plastic case that came with the card in the first place. Better still, place that card (maybe even in that case) inside another storage device, like a card wallet or box. CF cards are designed to withstand the rigors of professional use, but they’re nowhere near indestructible. A ruined connection—which might be caused by something as simple as pocket lint or a few specks of dirt—can render a card unreadable.
4. Experts say you should format often, and format in camera rather than in the computer. I don’t have any personal experience testing this, as I’ve formatted in camera prior to practically every photo shoot I’ve done for more than a decade. That means I’m following the rules, at least. I have had the occasional corrupt file or unreadable card, but usually I can trace it to something other than a bad format. Apparently the file structure in any given camera is different from another, and most definitely different than the way a computer formats a card. So if you want to go from your Sony point-and-shoot to your Nikon DSLR, you’d be best served, they say, by downloading the images and then formatting the card in the Nikon. And to be clear, don’t just delete the data with the Trash Can icon on the camera. There’s a big difference between removing files and formatting the card. The latter is the best practice for data security.
5. Want to protect yourself from the moment of capture? Consider investing in a camera with multiple card slots. Many cameras have multiple slots to accommodate two media cards so you can either have increased storage capacity or, my definite preference, data redundancy. As the file is written to card A, a duplicate is written to card B. Then when card A turns up corrupt, you can always defer to the duplicate copy of the image files residing on card B.
6. One more thing. If you’re using an SD card, make sure the little write-protection switch on the left side of the card hasn’t been flipped. If your card appears unreadable, it’s wise to first ensure you haven’t accidentally flipped this switch to the locked position. Likewise, if you’ve managed to capture your one-in-a-million shot on an SD card, you might consider intentionally flipping that switch to prevent yourself from accidentally deleting it—something I would most certainly attempt to do.
