Fast Forward's Help File

QYour advice about backups came too late for me. My hard drive died, and I would like to get back some of the files on it, but I don't know anything about data-recovery services.

AData-recovery service is the computing world's equivalent of brain surgery -- in terms of the stakes involved, the difficulty of the work and the cost of the procedure.

If you're very lucky, a local computer shop can pluck data off a crashed hard drive using just software tools. Last year, for example, I paid about $170 for this work.

More often, however, a data-recovery firm will have to take apart the drive to try to rescue its contents. This can cost more than a new computer. For example, Kroll Ontrack ( http://ontrackdatarecovery.com) says it charges $800 to $1,400 for a typical recovery job. At DriveSavers ( http://drivesavers.com), that type of repair typically costs $1,500.

Some drives suffer too much injury -- either from the initial crash or from unsuccessful software fixes that exacerbate the damage -- to permit any data recovery. Kroll Ontrack estimated that 20 percent of the drives it sees are hopeless, and DriveSavers said it must give up more than 10 percent of the time. That's why you should back up your files early and often.

Why are the videos shot with my miniDV camcorder so big -- 13 gigabytes for an hour of video -- compared with DVD movies?

The mid-1990s DV (digital video) standard didn't benefit from subsequent advances in video-compression technology that allow DVD and newer formats to shrink video clips.

To keep your drive from being overrun, save your movies in a more efficient format after editing them. For example, in Apple's iMovie '08, go to the Share menu and choose "Export Movie..."

Rob Pegoraro attempts to untangle computing conundrums and errant electronics each week. Send questions to The Washington Post, 1150 15th St. NW, Washington, D.C. 20071 orrobp@washpost.com. Turn to Thursday's Business section or visit washingtonpost.com anytime for his Fast Forward column.