The Adobe Photoshop Lightroom 3 Book: The Ideal Computer Setup for Lightroom
The ideal computer setup for Lightroom depends on the size of the files you intend to work with. The raw file captures you will be working with may range in size from 6 to 25 megapixels, and the larger files will certainly place more demands on your computer resources. So, when looking for an ideal computer to run Lightroom, you definitely need to take the typical image file sizes into account. The most important factors affecting Lightroom performance are the processor speed and the amount of RAM that is available for Lightroom to use. This is followed by the speed and size of the hard disk and, to a lesser extent, the processing power of the graphics card. Lightroom is optimized to run on the latest Intel computer processors and, at a minimum, you need a Macintosh Intel processor computer with 2 GB of RAM, running Mac OS X 10.5 or later. And on the PC side, you need an Intel Pentium 4 with 2 GB of RAM, running Windows 7, Windows XP with Service Pack 3, Windows Vista Home Premium, Business, Ultimate, or Enterprise.
You will benefit from having as much RAM as possible, but you should take into account that the operating system and any other open applications will also consume some of that RAM. For example, if you happen to have just 2 GB of RAM installed in your computer, the operating system will use about 200 MB, while another 50 MB might be eaten up by various utilities. And that is before taking into account other, more memory-intensive applications that may be running in the background. So, if you double the amount of memory installed on the computer to 4 GB, you could easily triple the amount of RAM that is effectively made available to Lightroom. Keep in mind that with most laptops, you are probably limited to a maximum of 4 GB of RAM anyway, but if you have a desktop machine, you can probably install a lot more. Judging by the reports from various power users, you should see significant benefits in performance if you install 4 GB of RAM or more on a fast desktop computer. This is especially the case now that Lightroom is able to run as a 64-bit program and can, therefore, access RAM beyond the previous 4 GB limit.
The graphics card does not play such a vital role in Lightroom's overall performance. You simply need a graphics card that is capable of running the screen display at its native resolution. You don't necessarily need an ultrafast graphics card. For example, all the Apple Mini and MacBook computers, with the Core 2 Duo processor, use 64 MB of the system RAM to run the graphics display. As long as you have a suitable amount of memory installed, the amount of memory that's devoted to the graphics display should not necessarily limit the speed at which you can work in Lightroom. That said, video card performance and Open GL compatibility are important factors if using Photoshop CS4 or later.
On both the Mac and the PC platform, a default Lightroom installation installs the Lightroom catalog folder (that contains the catalog and previews files) inside the user's Pictures or My Pictures folder. As your catalog grows bigger, these catalog files will increase in size, although there are options in the Preferences to limit how long the 1:1 previews are preserved, automatically deleting them after a certain number of days. Don't forget that the Camera Raw cache may also be allowed to grow beyond the default 1 GB limit, and this, too, can consume more disk space.
The main considerations when selecting a hard drive are the interface type, hard drive configuration, speed, and buffer memory. All these factors affect the overall speed. Let's start with the interface connection. Internal drives usually offer a fast ATA interface connection, so one option would be to add more internal drives. I have learned from experience to be wary of relying too much on working files being kept on internal drives. Twice, I have had an internal power unit die and had to physically remove the drives and place them in a temporary drive housing in order to access the data. For this reason, you could choose to store all the Lightroom catalog image folders on fast external drives. This would allow you to free the main computer hard drive from an accumulating library of image folders. However, with some of the newer computers, it is actually much easier now to swap out the internal drives and move them from one machine to another. So, I am actually inclined to use internal drive units because they offer a faster internal interface connection speed.
Several external connection types are available. A USB 1 connection limits the data transfer rate and should be avoided. Instead, choose a USB 2 or FireWire 400/800 connection. You can now also buy Serial ATA (SATA) drives that promise very fast rates of data transfer, but you might need a PCI card that provides a SATA connection from your computer.
The hard drive spindle speed determines how fast data can be written to and retrieved from the disk drive unit. Most 3.5-inch desktop drives have a spindle speed of 7200 RPM, whereas the smaller 2.5-inch drives found in laptops and portable bus-powered drives mostly run at a speed of 4200 to 5400 RPM. You can get 7200 RPM 2.5-inch drives, but they are more expensive and are usually only offered as a custom option when buying a laptop. You can also get 3.5-inch drives that offer speeds of around 10,000 rpm, but they are expensive and the maximum storage space is only around 300 GB. Extra disk buffer memory helps take the pressure off the disk drive activity, which can also lead to improved drive performance.
Multiple hard drives can be configured in a variety of ways, including the RAID system methods described below. You need a minimum of two disks to configure a RAID system and most off-the-shelf RAID solutions are sold as a bay dock that can accommodate two or more drives with a built-in RAID controller. For some people, RAID is the perfect solution, but for small photography businesses, it can be overkill. Let's start, though, by looking at some of the more popular RAID configurations and how they might suit a digital photography computer setup.
A striped RAID 0 setup allows you to treat multiple drives as one. Here, two or more drives can be joined to become a single drive volume. RAID 0 is useful if you require fast hard-drive access speeds, because the drive access speed increases proportionally to the number of drives that are added. If you have four 500 GB drives configured using a RAID 0 system, you'll end up with a single 2 TB volume, with a hard drive access speed that is four times that of a single 500 GB drive. This setup might seem like a good idea for improving the data access speeds, but the disadvantage of such a setup is that if a single drive should fail, the entire RAID system fails, too, and all the data that's on it will be lost. A RAID 0 setup is, therefore, ideal for use as a Photoshop scratch disk but not for storing essential data you can't afford to lose.
A mirrored RAID 1 system stores an exact duplicate of all the data on a backup drive. As data is written to one drive, it is updated to the other drive, too. The main advantage of a RAID 1 system is that, if any single drive within the system fails, you can swap it with a new one, and the data stored on the mirrored drive automatically rebuilds a copy of all the data to the replacement drive. RAID 1, therefore, offers you the most secure method for storing important data, such as an image archive, providing increased data integrity and fault tolerance. The downside is that you'll need double the disk space to store all your data. For example, a mirrored RAID 1 drive setup using two 1 TB drives would allow you to store only up to 1 TB of data.
Mirroring can provide security against immediate drive failure, but it does not offer a complete backup protection solution. Mirrored drives are necessary for businesses that must have absolute access to the data 24 hours a day, 7 days a week. But mirrored systems don't necessarily provide the full data security you would expect. For example, if the directory becomes corrupted, the continuous mirroring copies the corruption to the mirrored drive. This could happen before you are even aware of the problem, leading to a loss of data. For absolute protection, scheduled backups need to be carried out to a secondary storage system, which should, ideally, be kept off-site.
A mirror of stripes
It is, therefore, tempting to look for a solution where it is possible to store large amounts of data on a fast, striped volume that is also combined with built-in mirroring backup. One such option is a RAID 0+1 setup, which requires four disks. The first two disks are configured using RAID 0, creating a single volume but with twice the disk access speed of a single disk. The other two disks are configured to create an overall RAID 1 setup, in which the data on the RAID 0 volume is safely mirrored across the two backup disks. A RAID 0+1 system is, therefore, both fast and secure, but such systems do come at a price. Plus, they can be quite noisy and are not particularly energy efficient.
RAID 5 has gained in popularity recently. This requires a minimum of at least three drives and allows you to store data more securely and more economically through parity striping. In practice, a RAID 5 configuration allows you to use the full drive storage capacity, less the capacity of one of the single drive units, and provides complete data backup should any single drive fail. So a 4 TB RAID 5 using four 1 TB drives would be able to store up to 3 TB of data. RAID 5 offers the most economical form of storage that can withstand a single drive failure, but the write speeds are necessarily slow.
The Drobo storage system (www.drobo.com) uses what is described as "virtualized storage," which appears to be very close in functonality to the way a RAID 5 system works. The Drobo system allows you to easily upgrade individual drives, thereby keeping pace with your data expansion needs. It is kind of scary to trust your valued data to a proprietary storage system, but arguably less so if you take the precaution of combining this with scheduled backups to a separate Drobo setup.
Just a bunch of disks
There are varied opinions about which is the best way to manage a photography archive storage system. In my view, RAID storage is ideal but not the best solution for all photographers. A perfect solution would be to have a high-capacity RAID drive system that is capable of storing all your images securely on a single RAID unit. I have seen photographers work with such setups, but even so, it is quite costly to have a multi-drive unit that holds all your data running continuously and consumes lots of power just so that, once or twice a year, you can dig up a file you shot six years ago. If you analyze your storage requirements, you will most likely find that the vast majority of the files you access are those shot in the last few years. When you think about it, the files you need to work with on a regular basis can probably be accommodated on a few standard single-drive units. This leads to a simpler solution known as "just a bunch of disks," or JBOD for short. With a JBOD setup, you can have a file storage system that is scalable to meet your expanding storage needs, which is not only economical to maintain but also reliable (providing that you maintain a proper backup strategy). In my office, I use two internal 2 TB drives to store all the current catalog files and back these up to two external 2 TB drives. I also have eight other 250 GB drives that are used to store all of my older raw and master file images that date back over the last 16 years, plus another eight similar drives that are used for backing up to. Most of the time, I don't need to have these external drives running, and I back up regularly to the main two 2 TB drives. Whenever I need to access older images, I can switch on the necessary hard drive, as directed by Lightroom. JBOD can never be as foolproof as a RAID system, but it may be more appropriate for those photographers who think this would be an acceptable enough solution for their storage needs.
The ideal system?
These days it is worth purchasing a computer that has plenty of free internal space that allows you to install additional internal drives. For example, the latest Intel Mac computers have enough room to fit three extra drives. You can, therefore, equip a modern Intel Mac with either an internal mirrored RAID 1 or a striped RAID 0 setup. These will have to be controlled by software on the Mac via the Disk Utilities program. In the past, software-created RAIDs were a lot slower than a dedicated system with a hardware controller. The read/write speeds from a software RAID will still be slower than a true dedicated RAID system, since a software RAID will have to steal some of your computer processor cycles. But these days, the speed loss is not as bad as it used to be. A software-driven, internal striped RAID 0 can increase disk access speed by about 45 percent, but it comes with the inherent risk of losing all data in the event of a single disk failure. A software-driven, internal mirrored RAID 1 reduces speed by about 25 percent, but it improves reliability. Finally, if you ever need to see an overview of your system setup, you can go to the Help menu and choose System Info. This opens the dialog shown in Figure B.27, which also includes the Lightroom serial number (which isn't shown here for obvious reasons).
Figure B.27 The Lightroom System Info can be accessed via the Help menu.