GPS for Dummies.pdf - Engineering Surveyor

Chapter 8: Digital Mapping Hardware Considerations149If you plan to collect lots of map data, you’ll definitely need a high-capacityhard drive for storage. At 10MB per data file, 100 files quickly can consume agigabyte of disk space. Although you can get by using smaller hard drives, I’dopt for at least an 80GB drive.If you decide to get serious about computer mapping, I recommend that youpurchase a second internal or external hard drive to exclusively store yourdata. A second drive provides more performance and is easier to maintainand manage files. And because a second drive currently can be had for a littlemore than a dollar per GB, the bigger the better.CD and DVD drivesJust about every commercial software manufacturer uses CDs to distributetheir products. Digital map manufacturers are no different; they extensivelyuse CDs for map data. For example, the National Geographic Back RoadsExplorer (a whopping 16-CD set) provides topographic maps for the entireUnited States. You can run these CDs on any CD drive; the higher the readspeed, the faster the map data will load and display.Having a CD drive that can write (burn) CD-ROMs is way useful if you plan todownload large amounts of map data from the Internet. Because data filescan be very large, archive the data on CDs instead of cluttering your harddrive with infrequently used files. If you’re not going to be archiving mapdata, consider using CD-RWs (rewriteables) because you can delete files fromthem, using them again and again.Computers are now commonly equipped with a DVD drive, which can readboth CDs and DVDs. DVDs rock because they can store a whole lot more datathan a CD; compare 4.7GB on a DVD versus a relatively paltry 700MB on a CD.As DVD drives become more commonplace on computers, expect map softwarecompanies to start offering their products on DVD media. This will makelife easier for vendors who currently distribute map data on multiple CDs.As this book goes to press, DVD standardshave yet to be agreed on (by the manufacturersas well as the ever-important consumers).Check out this alphabet soup: There are DVD-ROM, DVD-R, DVD-RW, DVD+R, DVD+RW, andDVD-RAM formats. Some manufacturers areDVD souphedging their bets on the standards race byoffering multiformat DVD drives. If you’re in themarket for a DVD drive, I’d certainly look for amultiformat drive until a single DVD standardemerges.