iMovie: Format external hard disks as HFS Extended for best performance

Because digital video can take up a significant amount of hard drive space, storing your digital video on an external hard disk can be a convenient way to prevent your Mac OS X hard disk from becoming full.

Format your FireWire or USB 2.0 hard disk as HFS Extended for best performance with iMovie. Some hard disks come from the factory in other formats that are not as well suited for iMovie.

Formating an external hard disk is usually done when it's brand new. If you want to reformat a drive that already contains data, be sure to back up the data to another drive beforehand. NOTICE: Reformatting a hard disk will permanently erase all of the data on it.

Tip: You can check the format of your hard drive by clicking its icon in Finder and then choosing Get Info from the File menu. The format is displayed in General information in the Info window.

To format a hard disk as HFS Extended

Note: Formatting a hard drive will permanently erase all of the data on it. Formatting an external hard drive is usually something you'll do when it's brand new. If you want to format a drive that already contains data, be sure to back up the data to another drive beforehand.

1. Connect your external hard drive to your computer.
2. Open Disk Utility from the Utilities folder in Applications.
3. Select the name of your hard disk in the left column of the Disk Utility window so that it's highlighted.
4. Click Erase to show the formatting options pane.
5. From the Volume Format menu, choose Mac OS Extended.
6. Click Erase (in the lower-right corner).

Note: USB 2.0 hard disks work best with iMovie when directly connected to your computer. Disks connected to an Airport Base Station are not supported with iMovie. USB 1.x disks are not supported with iMovie.