Memory Card Housekeeping

Author: Sara Goodnick

  • Formatting-quick or full? Do you know the difference?
  • Deleting? When and how is best?
  • Change cameras = change cards?
  • What brands to buy, and what size?

First, when you get a brand new memory card, you put it into the camera, and have the camera “format” it. What is happening here? The card has 1s and 0s arranged in cells or segments and the computer puts them all into its own type of filing system.


Next, you record your images, download to your computer, and also back them up onto another device. Remove your card, and then what?  Put it back into your camera and format it again.

However, the information from those older images is still on the card. They aren’t really erased unless you get some professional help with it. The camera and most other software cannot get to them, but they are still lurking there. I know a pro who recently had a card get corrupted, losing some valuable images from a commercial shoot. When he had them retrieved, using a specialty company, there were over 5,000 images discovered on that card he had just been formatting in camera over and over again.

Here is where a full format, or “wiping” comes in. If you want a truly clean card, you will want to use your computer to do a full format. It will remove all the old information, and possibly prevent corrupted files. (It is also a good way to foil spies-if you’re bothered by that possibility!)

Link to the SD Association with a formatting program for many Windows and Mac systems:

Link to full formatting for Windows:

Link to full formatting for a Mac:

After doing a full format, which will take several minutes, you must also format the card in the camera as usual. Then, to be safe, go out and take a few test shots just to be sure there is no corruption, and all is ok.

Take away:

  1. You should not need to do a full format more than a few times a year. Some pros do a full format before every big job.
  2. Always format a card in the camera you are using. This will overwrite any old images and set up the camera’s own filing system.
  3. Do not put a formatted card into a different camera than the one it was formatted for unless you reformat it in that camera. Which, of course, will overwrite the old images.
  4. Never delete in camera. Download those images and delete from your computer.
  5. Buy name brand cards-Sandisk and Lexar are some of the best.
  6. Buy medium sized cards. You don’t want to be putting all of your eggs in one basket with huge cards, nor do you want to be changing cards all the time when they fill up quickly.
  7. If you have a choice, opt for a camera with dual card slots. Even if one card gets corrupted, the other will probably be fine.

Sara Goodnick is a trip leader with Arizona Highways Photo Workshops.