How-To: Memory Cards and Image Safety

Last update: 16 April, 2013

While some hobby photographers shoot mainly in their neighborhood and take only few images a day, others pay thousands of dollars to travel to exotic locations, shoot thousands of images, and it feels more like “serious business” than a hobby. Since you are reading this article, I’m guessing that you belong to one of the above categories, fall somewhere in between, or are a professional doing paid assignments. Furthermore I’m going to guess that you hate to miss photographic opportunities or lose images that you’ve previously captured (and have not yet transferred to your computer).

So what are you mostly worried about?

  • Great images surround you, but you don’t have a camera at hand, your battery is empty or your memory card is full.
  • You damaged or lost your camera or your equipment got stolen.
  • You lost a memory card or accidentally erased data from it.

This article describes workflows of different “intensities” and gives advice on how to best handle memory cards and manage images while on a short photographic walk or on a photo-tour spanning several weeks or months.


General Recommendations

  • Don’t be too concerned with the longevity of modern memory cards (2013). With a rating of 100 000 write-cycles [1], you can expect a card to function trouble-free for 54 years if you fill it up with images five times a day, each day.
    • Being environmentally friendly, we cannot recommend using memory cards just once, then keeping them as a backup. It is far better to copy images to your computer, then backup your entire hard-drive.
    • Buy “medium” cards: not the cheapest or oldest, but also not the most cutting-edge with the highest capacity. Cards with higher capacities generally have a lower life expectancy [2].
    • Buy from reliable retailers as memory cards are quite easy to counterfeit.
    • If a card fails once, it will surely fail again (possibly in a very inappropriate moment), so do yourself a favor and throw it away.
  • Many smaller-capacity cards or fewer larger ones? This question gets debated a lot, but there’s no clear recommendation. With smaller cards you swap more often and have to manage a larger number of cards, so the risk of losing or mixing them up is higher. On the positive side, if something unfortunate does happen, you lose fewer images. With larger cards it’s exactly the opposite.
  • Write a number on each of your memory cards so you can easily distinguish them, even if they all look the same.
  • Decide how to logically separate used from “clean” cards. Some people place them in different pockets, others carry them in cases and place full ones facing one way and empty ones the other. Whichever way you do it, make a habit of it.
  • Keep exposed cards separate from the camera bag, because no one would steal a card alone but someone might steal the bag with all its contents.
  • Train yourself to always hit “play” at the beginning of a day and always start with a freshly formatted card. You don’t want to leave the house with a camera but without a memory card or with a card that is half full.
  • It’s better to “format” a memory card than to “erase all” images on it:
    • “Format” resets the table of contents on the card, which has the following advantages:
      • It’s very fast,
      • The entire capacity of the card is freed up for later use,
      • The directories and files that were previously on the card are no longer referenced by the card’s table of contents, but they are still there and much easier to recover by specialized software,
      • Don’t worry about the format process writing each time on the same physical area of the card (thus wearing it out). Modern cards have clever algorithms that make sure that all portions of the card get used equally often [1].
    • “Delete all” goes through all directories that the camera knows of and erases their contents recursively. This has the following disadvantages:
      • It takes longer than formatting,
      • Images shot with other camera bands usually remain on the card, so not all space is freed up,
      • The removal of directories and images is more thorough, which makes it more difficult for recovery software to rescue anything,
      • Even though more areas on the card get overwritten, it’s still not a reliable test for corrupted memory locations.
    • Always format a memory card in the camera you’ll use it with.
    • Formatting a card (even the so called “low-level format” in the camera) does not test the card’s integrity completely and does not overwrite all memory cells with zeros. To achieve this, you need a low-level formatting utility on your computer. TODO: List at least one for MacOS and one for Windows.
  • Many laptops allow you to directly insert an SD card, but if you don’t have one of those, it’s quite a lot faster and more convenient to use a card reader than to connect the camera via USB cable with the computer.
    • Lexar’s (apparently excellent) customer support suggests strongly that you first insert the card in the reader and then attach the reader to your computer.


Workflow A: Shooting Lightly

  • Buy several memory cards, each large enough to comfortably hold a day’s shoot.
  • Format one memory card in your camera and stow it in a safe pocket of your camera bag:
    • This is your backup card, just in case something goes wrong.
    • At least once a year swap this card with one of those that you use regularly.
  • Keep all other memory cards at home in a stack, the one used most recently sitting at the bottom.
  • Before leaving home, make sure that there is a fresh memory card in your camera:
    • If it’s been more than a week since your last shoot, format the card. This is just a very basic operational test your camera, battery and card. In fact, make the test a bit harder and more practical: shoot a picture of your business card. Now if you lose your equipment, some kind soul would know who the rightful owner is.
  • In the field: don’t swap cards, don’t format cards and don’t delete images from the card.
  • When you get back from a day’s shooting, import the card to your computer then place it at the bottom of the stack of used memory cards:
    • Don’t erase or format the card just yet. If something happens to your computer, the images will still exist on the card (for as long as it takes you to use all other cards in the stack exactly once).
  • Before putting the camera away, take a memory card from the top of the stack. If it’s locked, unlock it (only for SD cards), put it in the camera and hit play. You copied these images to your computer a few days ago, didn’t you? Now format the card in the camera.
  • Back up your computer data.


Workflow B: Shooting Seriously

Before the Trip

  • Be careful with new gear. Get to know new equipment well ahead of the trip and check if it works properly. Decide if it’s worth bringing along the manuals for your equipment. If you will be taking a tablet or a laptop with you, consider bringing the manuals in PDF form.
  • Backup body. How tragic is it if your only camera breaks on the first day of your trip? Or do you already have a backup body? Are you willing to invest in one? Will you be satisfied with the image quality of a (backup) compact camera? Do you know your backup camera as well as the primary one? Does it take the same memory cards and batteries or do you need to lug yet another charger with you?
  • Don’t be a Show-Off. Cover all brand names with black tape and replace that shiny “Canon 5D Mark III” or “Nikon D800E” camera strap with something less flashy and more practical.
  • Electricity and battery power. Different countries use different plugs [3], so buy an adapter if needed and bring a power strip so you can plug in several devices at the same time. Think about how often you will be able to recharge your batteries and then decide how many spares you need. Number each battery. Even if they all look the same, now it’s easy to distinguish the empty from the full ones. Designate a pocket for the empty batteries.
  • Memory Cards. How many you need depends largely on your shooting style, but you’ll probably need more than you initially think. On the other hand, if you fill up half your cards during the first quarter of the journey, you’ll probably be OK, since you tend to shoot more at the beginning of a trip. Also you can buy empty cards in virtually any medium sized city in the world.
  • Choose a back-up strategy for the road (let’s call a memory card with images on it an “exposed card”):
    • No backup. Just shoot and do your best to not lose any memory cards, not format any exposed cards and (in case you need to free up some space when all your cards are full) only delete unwanted images from your cards. Obviously this is quite a risky “strategy” which makes exposed cards infinitely more valuable than empty ones. So be sure to bring enough cards and be very, very careful with the exposed ones.
    • Backup in camera. Some bodies (like the Nikon D7000 and bodies above it), have two card slots and can write each image on both cards. Be sure to keep the exposed backups separate from the exposed originals.
    • Portable Storage Devices (PSD). Basically a hard-drive with an integrated card-reader, like the HyperDrive ColorSpace. TODO: Are there any others? Here is my review of an older version of this device. Most portable and cheapest way to back up memory cards without a computer.
    • Tablet / iPad. If you don’t shoot much, you could backup your images on a tablet or an iPad. If you shoot a lot, you can use something like this. TODO: Are there good solutions for the non-Apple tablets? Of course, by bringing a tablet you have one more appliance and one more charger to keep track of.
    • Laptop. There are many advantages: you can backup, review and delete images, and you can start editing. You can even bring a portable hard-disk and make an additional backup. A laptop is a great idea, but it is sensitive to shocks, moisture and temperature extremes, adds even more weight to your luggage, requires a dedicated charger and is one more valuable thing to worry about. By the way, don’t forget to bring a card reader if your laptop doesn’t have a built-in one.
  • Label everything. Say you lose a card or your camera bag gets stolen and then recovered by the police or by a good Samaritan. How are they to know where to return the items? Do yourself a favor and:
    • Place a business card or a piece of paper with your contact information in your camera bag.
    • Check if your camera allows you to specify copyright metadata. The Nikon D7000 and Olympus OM-D support this, surely many others as well. If you specify your name, telephone number and e-mail address in the copyright metadata, these cameras will add that information to each image that you shoot.
    • If you still use CF cards, write your e-mail address or your telephone number on each card. SD cards are too small for that, but see the next point for one other trick you can do.
    • After you format a memory card, take a picture of a business card or of your contact information and only then consider the card ready for use.
  • Weight. After you’ve decided which equipment to bring on the trip, fill up the camera bag and carry it around for two hours. Too heavy? Leave some things at home.


During the Trip

  • Before leaving your hotel room in the morning:
    • Make sure that you have a fresh card and a charged battery in the camera,
    • Ensure that you have enough memory cards and charged batteries in your camera bag,
    • Store your backup device (laptop, tablet, HyperDrive) in the hotel safe or hide it in your room. Carrying it in your camera bag is a bad idea because if the bag gets stolen, you lose everything.
  • Whenever there is a pause in the photographic action:
    • Swap cards if the one in your camera is almost full:
      • Lock “used” SD cards,
      • Store full cards in a specially designated pocket, ideally not in your camera bag.
    • Swap batteries if the one in your camera is almost empty:
      • Store empty batteries in a specially designated pocket of the camera bag.
  • After returning to your hotel room:
    • If you have a backup device (laptop, tablet, HyperDrive):
      • Backup the images of the day,
      • Backup the backup device (in case you have a laptop and an additional backup hard-disk)
      • Format all used cards in the camera.
    • Charge the empty batteries
    • Plan the agenda for tomorrow
    • Go to bed early

After the Trip

  • If you are a Lightroom user, have a main machine but used a (different) laptop on the trip, and if you did any editing along the way:
    • Select the images from the trip and “Export as Catalog”.
    • “Import as Catalog” on your main machine.
  • Otherwise simply upload all images from all memory cards onto your main machine.
  • Back up your computer data.
  • Without erasing or formatting the cards from the trip, place them at the bottom of the “ready to use” stack of memory cards.
    • If you have any SD cards, unlock them.


Comments? Questions?

This article is supposed to grow and turn into an Internet reference page on the handling of memory cards and making sure that your images are safe from the moment of capture up to importing them on your computer.

If you notice any errors or omissions, or if you have any questions, don’t hesitate to contact us or post a comment below.


  2. “newer technology to increase the storage capacity of a card provides worse write endurance”