Recovering Erased Images/Data from Your Memory
Losing images is perhaps one of the biggest, yet little-thought-about fears of many professional photographers and hobbyist shooters. Unfortunately, there are people out there that do not know how to recover images if they are lost. I talked to a few industry experts, asking them to share their knowledge about image recovery and software.
Seth Resnik, David H. Wells, Ziv Gillat (creator of the Eye-Fi card) and John Christopher of DriveSavers, Inc. all shared their insights with me.
1. Many people are afraid of accidentally deleting from their memory card an image that is important to them. How exactly can you get it back? Are there programs? What do you recommend?
Seth: I always import into two different drives, just in case data gets damaged. I also tend to use smaller cards, and change them, to avoid the problem altogether. I would much rather use two or three 8GB cards on a really important shoot than a 32GB card, just to spread the data across several cards. I still use large cards for their convenience, but if it is really, really a critical shoot, I will use multiple smaller cards.
That said, there is still Murphy's Law, and eventually you will find a corrupt card with important images. I have had very good luck with several recovery programs including Data Rescue, Photo Rescue, Lexar Image Rescue, and Sandisk Card Photo Recovery.
Ziv: There are a few, and I haven't used them in a while, but the process is called "undelete." So if you just search on Download.com for undelete or unerase programs, you'll find a few. Sandisk even ships a coupon for their favorite with their highest end cards, and so does Lexar. But I forgot their names. I used to use one on Windows that did a good job, but haven't for years, and I'm sure that since I've last used it, new ones have popped up. I'll spend some time online and see if I can find the stars, and will email you again.
David: I carry three different card-recovery programs on my laptop for recovering images off my flash card if I make a mistake. The one thing I do not want to be doing in a panic is looking on the web for such a program, so I carry them with me. I usually use two or even three programs to get the lost files back.
The big issue is they are ALL Windows interfaces for engineering minds, so they take some focus (as well as trial and error) to make them work. They are: Lexar Image Rescue, PhotoRescue (I have an old and new, since they work differently) and San Disk RescuePRO.
I start with the card manufacturer's rescue program, though that may or may not work.
John: I think practically every owner of a digital camera is afraid of losing their pictures, and it's certainly easy enough to press the "trash" button while reviewing a photo. Most of the customers that come to DriveSavers for data recovery typically try to recover deleted or reformatted media themselves by using some kind of software. We don't have a specific recommendation for software, but some of the flash memory vendors offer free software, or have recommendations on their website. You should see SanDisk's and Kingston's here.
All of them have one thing in common: They're trying to recover photos, videos or sound files from once-in-a-lifetime events such as the birth of a child, a wedding, or even a vacation.
2. How easy is it to recover images and data?
Seth: Each piece of software works differently, and while it is time consuming, most of them work quite well and quite easily.
Ziv: Depends how the corruption occurred, or if the person did a delete or a high-level format. Here are the details:
o A card has a file system on it, and typically—with cameras—it's a FAT or FAT32 file system. It can get corrupted easily, if you remove the card during a write, or if the power goes out during a write, etc. Reading and cutting the power off, or removing the card during a read operation is fine. But killing the operation in the middle of writing can cause corruption. FAT and FAT32 are not as fancy as NTFS (Windows) or HFS+ (OSX), which are file systems that can track errors, and correct for them. So when you get corruption with HFS+ or NTFS, you can, in many cases, fix it using disk-corruption utilities. With FAT and FAT32, it's a bit harder.
o So if there is corruption on the card, you can either use OSX's Disk Utility, or Windows' built-in disk utility, and you may be able to get your images back.
o If not, you should use an aftermarket file undelete program.
• If you've deleted a file, it's still there. The file system just clipped a bit in the file, and told the card that if it needs to, it can write over it. But immediately after erasing a file in the camera or on a computer, it's there in its entirety.
• As you write files, the file's blocks will get overwritten.
• Same if you format. There are two kinds of format—high level and low level. High level just changes the boot partition, and tells the card to overwrite the blocks. The blocks actually still contain the data, and as you write the new content to the card, those blocks with the old data get overwritten with new data. But again, immediately after a high-level format, all the content is still there. It's just hiding.
o A low-level format writes 0's over all the blocks. Canon does it, as an option, to REALLY delete the content. So if you've done a low-level format you've lost all your photos, and no undelete operation can be done.
The other thing that can happen with SD / CF / Micro SD cards is that the controller or the flash can go bad. Typically, the controller goes bad—not the flash. In that case—and this is super advanced—a company can take the flash portion off, put it into a special machine, and read the contents off the flash. Or, the firmware in the controller can go into a confused state, and a company (memory card company) can fix the firmware, and try to revive the card. Those are special corner cases.
John: If the image was simply deleted (trashed) off the camera card, there is a very good chance of getting it back. The key to a successful recovery is to stop taking pictures (or change to a different camera card) so the image won't get overwritten if you take more photos.
3. What about after formatting the memory? How easy is it after that?
Seth: Definitely tougher, but I have successfully recovered data from a card that was formatted multiple times.
John: Once the card is reformatted, it is difficult to determine the chances of getting any images back. It really depends on how the camera formats the card. Some cameras simply wipe out the directory (the table of contents, in a manner of speaking). Other cameras overwrite the data completely. Even if commercial software fails to get the images back, there is still a chance that we can.
Many of the camera cards we receive here are physically destroyed, yet in most cases, we are still able to recover the data.
4. What are the most frequently asked questions that you get on hard drive information recovery, and what are your answers?
Seth: The answer to most of the questions is simply that you can't have too many backups, and the best system is one that avoids problems by having multiple backups.
David: They're actually the questions you asked.
John: The most frequent question is: How (or why) did my hard drive fail? We always try to help our customers understand that hard drives are mechanical devices with moving parts inside. We created a hard drive simulator that runs on our website (or can be downloaded to an iPhone, iPod Touch, or iPad). It provides a visual aid and simulates all types of drive failures, and offers recommendations for backing up. Here's a link.
In addition we recently complied the following tips for protecting digital images:
Top Safety Tips for Protecting Digital Image Files
With the advent of digital photography and flash memory, a whole new set of potential problems has evolved for photographers. DriveSavers Data-Recovery Engineer Chris Bross has assembled the following list of tips on how to handle flash-memory cards properly, and help prevent the potential loss of precious photographs:
• BACK UP YOUR IMAGES! - Protect yourself and your irreplaceable images by backing up onto CD, DVDs, tapes, online storage or an external hard drive. This will help guard against data loss when (not if) your hard drive crashes unexpectedly.
• TRANSFER YOUR PHOTOS - Copy the image files from the camera's flash memory to a computer's hard drive a soon as you can. We recommend that you do not delete images or reformat the memory card while it is still in the camera. Wait until all photos are transferred and verified.
• FOLLOW INSTRUCTIONS - Take care when removing flash memory from the camera or card reader. Avoid deleting or corrupting images by using the eject command on the computer or moving the card icon from the desktop to the trash/recycle bin before physically removing the card.
• VERIFY THE TRANSFER - Open the images on the hard drive before reformatting the card.
• MAKE MORE THAN ONE COPY - Back up your backup media, and keep a duplicate offsite in a secure location.
• PROTECT YOUR FLASH MEMORY CARDS - Use the plastic holder when carrying them around. Simple static buildup can zap the card and make it unreadable. There are other dangers as well, such as breaking a card in your pocket or putting the card, along with your clothing, in the wash.
• AVOID EXTREME TEMPERATURES - Heat, cold and humidity can wreak havoc with digital equipment, especially flash memory.