text: Image mode creates one-to-one mapping of logical block addresses (LBAs) between a 
  volume and an MDisk (LU presented by the virtualized storage). Image mode volumes have 
  the minimum size of one block (512 bytes) and always occupy at least one extent. An Image 
  mode MDisk cannot be used as a quorum disk and no IBM Spectrum Virtualize system 
  metadata extents are allocated from it; however, all of the IBM Spectrum Virtualize copy 
  services functions can be applied to image mode disks. The difference between a managed 
  mode volume (with striped extent allocation) and an image mode volume is shown in 
  Figure 7-4. 