Digital Image Analysis is one of the fastest growing methods for determining particle size and shape. The Dynamic version of this technique as seen in the HORIBA Camsizer-L is gaining in popularity very rapidly. This instrument has been applied to many fields including glass beads, fertilizer, expanded polymers and soils and sediments. The capability to determine size and shape in one measurement in five minutes or less is very attractive. A logical extension of the work on soils and sediments is to migrate to samples originating from volcanic eruptions. This article will explore the proper measurement of these samples and how the data can be used to construct plume dispersal models.