The Need for Storage
The increased resolution of digital SLRs, the growth in the use of the RAW file format and 16-bit image editing have all led to larger and larger image files. These bigger files not only take up a significant amount of space on a memory card, but also occupy more space on the hard drives of our desktop and laptop computers. While a computer with a 60 GB hard drive seemed more than ample a couple of years ago, we soon discovered all that real estate was being consumed by a growing number of digital images.

To accommodate this ever-increasing amount of files, pros are expanding their use of alternate storage options, which include external hard drives and recordable discs, like CDs and DVDs.

Although adding a secondary internal drive to your computer is an option, recent natural disasters reveal the benefit of having an archival storage system that's easily portable. The ability to quickly escape a catastrophic loss of one's life's work by carrying it with you can't be underestimated.

“You hope that you don't have catastrophic events, but Hurricane Katrina brings to mind the idea of grabbing what you can and getting out of town," says sports photographer Dave Black (www.daveblackphotography.com). “Though I'm in Colorado and a hurricane isn't likely going to happen to me, it's important to know that I can take that external hard drive with me if I need to.”

Recordable Media
Just a few years ago, recordable discs grew in popularity as a source of storage because of their relative cost-effectiveness compared to hard drives. With capacities of up to 700 MB with CDs and 4.7 GB with single-layer DVDs, the price of recordable media was an attractive alternative at a time when internal large-capacity hard drives were prohibitively expensive. The cost of hard drive space has been dramatically reduced, but recordable discs still play an important role for archiving.

When it comes to storage, an important term that's used is “redundancy.” This means having an extra component that isn't absolutely necessary for everyday performance, but provides a backup to the system in case of failure.

Although many professional photographers possess more than a single hard drive for storage, they will also use recordable discs to back up their files. While the likelihood that multiple drives would fail simultaneously is slim, the presence of a completely separate storage medium provides added insurance that images won't be lost in the event of such a failure.

Black uses external hard drives and external discs for backup. “When I get back from an assignment, I just transfer the images from the laptop to the hard drive and DVDs so that I don't bog up my main computer,” he says. “I burn the DVDs using the laptop because it's just smart to have two systems. This way, I can work on e-mails or other projects on the main computer in the office. Once that DVD is burned, I transfer everything to the main computer directly from the external drives to begin work on the images.”

With higher-resolution cameras capable of filling up a 1 GB card so quickly, the viability of CDs as an archival storage medium has been diminished. In its place, DVDs have proven a feasible alternative. Technological innovations in the form of dual-layer DVDs (approximately 8.5 GB) and the promise of capacities of more than 40 GB with Blu-ray and high-definition (HD) drives and discs make recordable DVDs important tools for digital photographers.

Industry information indicates that optical discs may last between 100 and 200 years while rewriteable discs have a life of about 25 years. However, there are concerns that the dyes heated by the laser when burning may be subject to degradation over time, resulting in reduced life. Therefore, it's essential that you choose high-quality discs to maximize life as well as use alternative media, such as an external hard drive, to ensure that your images are protected.

Regardless of whether you're using discs or hard drives, it's a good idea to keep up with industry trends relating to storage. Recordable discs will likely be around for years to come, but be keen to when a recording medium is seeing the end of its run in the computer industry. Think of the fate of the floppy disk and consider the importance of the files you're storing with today's media, and you can see why keeping on top of changes is crucial.

External Hard Drives
Improvements in manufacturing and the power of the marketplace have resulted in a huge reduction in the cost of hard drives, which has proven to be a boon to photographers. With a 250 GB hard drive available for less than $200, and capacities reaching the terabyte range, the options available to us as photographers have not only grown, but have become more affordable, too.

External hard drives, whether in the form of a dedicated unit that sits on your desktop or a portable model that fits in your pocket, have quickly become the preferred archival storage system for many professional photographers.

While increased capacity has influenced this change, likely the biggest reason is the easy accessibility photographers have to their images. Since drives are connected via USB 2.0 or FireWire, you can gain access to any or all of the images on an external hard drive with ease. Where discs require you to pull them out of a sleeve and insert them into a computer, a hard drive makes the process as simple as drag-and-drop.

“When I arrive from an assignment, I'll download images to a secondary internal hard drive, which I use as a clearinghouse,” says photographer Carlton Ward (www.carltonward.com), who uses multiple 250 GB LaCie external drives. He often assigns individual projects to specific drives. “I will then copy those images to an external hard drive. Then I'll copy the contents of the internal hard drive to DVDs. That redundancy is definitely important.”

When it comes to portable external drives, one benefit is that power is derived from the USB 2.0 or FireWire bus rather than an AC power adapter.

Reliability
As with any tool used by pro photographers, reliability is a must. The specification that reflects the expected drive's life and reliability is its MTBF (mean time between failure) value. This value, measured in hours, represents the average amount of time that will pass between random failures of similar drives. The average is based on 1,000 drives of the same type. This rating ranges from 300,000 to 1,200,000 hours for most current drives. Remember, the MTBF isn't a reflection of a specific drive, but a large number of units of a similar type.

The MTBF rating has to be considered along with the drive's service life, which is the length of time a drive can be expected to perform reliably before its internal components begin to wear and fail. Although the MTBF rating alone might make it appear that the drive should last for decades, it's more than likely that the internal moving parts will eventually fail, putting the data at risk.

While this specification is helpful in differentiating the quality of drives, photographers often rely on firsthand experience when choosing a drive. This is where a personal recommendation and information provided by photographers on photo- and computer-centric message boards are helpful.

Features
Beyond capacity and reliability, another consideration for photographers when choosing a drive is rotation speed. Measured in revolutions per minute (rpm), the speed at which the hard drive disc moves will directly affect its ability to read and write data. The preferred speed for drives is 7,200 rpm, which is especially important if you're managing large numbers of high-resolution files. While 5,400 rpm is acceptable, slower drives deliver sluggish performance, especially when handling large, uncompressed image files. While such drives are less expensive, the delays they incur may not make the price worthwhile.

Because hard drives consist of moving parts, a unit's ability to dissipate heat is paramount. Heat can impact performance as well as reduce the life of the hard drive.

Most of today's single hard drives don't include a fan, but use the materials that make up the drive's housing to dissipate heat. Often made of polycarbonate, these drives also include vents (small openings to expel air) to help draw the heat away from the drive's internal components. The lack of a fan also makes such drives virtually noiseless.

Higher-capacity drives normally in-clude multiple discs, whose resulting heat requires the inclusion of a fan. These fans are efficient, but can sometimes produce noise levels that may be irritating to some. It's important to consider the noise of a drive when shopping around.

As our image libraries grow, so does our need to secure them. Thankfully, we have products that are proving to be both affordable and reliable.