

These instructions apply, for the most part, to other versions of macOS besides Catalina.

cdr file extension.ĭisk Utility creates the disk image file where you saved it in the Finder and mounts its disk icon on your desktop and in the Finder sidebar. DVD/CD master: Changes the size of the image to 177 MB (CD 8 cm).Read/write: Allows you to add files to the disk image after it’s created.Sparse disk image: Creates an expandable file that shrinks and grows as needed.Sparse bundle: Same as a sparse image, but the directory data for the image is stored differently.Click the Image Format pop-up menu, then choose an option:.Click the Partitions pop-up menu, then choose a partition layout.To encrypt the disk image, click the Encryption pop-up menu, then choose an encryption option.If the disk will be used with Windows or Mac computers and is over 32 GB, choose ExFAT.If the disk will be used with Windows or Mac computers and is 32 GB or less, choose MS-DOS (FAT).If the disk will be used with Macs, choose Mac OS Extended (Journaled) or Mac OS Extended (Case-sensitive, Journaled).With macOS, to create an empty disk image, launch Disk Utility by opening Launcher, go into the “Other” folder, and then click the Disk Utility icon.

Just create an image of that drive and store it.

You can fill an empty disk image with data, then use it to create disks, CDs, or DVDs. In other words, it’s a file that contains other files and folders. A disk image (.dmg file) is a file that looks and acts like a mountable device or volume. Using the Disk Utility in macOS, you can create a blank disk image for storage.
