This article explains how to backup to Iomega REV drives. This type of external drive can be a bit confusing for many users as the Iomega REV drives are formatted with the UDF filesystem. Depending on your version of Windows, Backup4all might see the Iomega REV drive as a CD/DVD/Blu-ray device.
This article explains how to backup on two external drives using the daily rotation scheme. You can use the mirror backup type to create an image of the source files or you can create zipped backups using incremental, differential and full backup types.