Shape factor causes disagreements when particles are measured with different particle size analyzers. Each measurement technique detects size through the use of its own physical principle. For example, a sieve will tend to emphasize the second smallest dimension because of the way particles must orient themselves to pass through the mesh opening. A sedimentometer measures the rate of fall of the particle through a viscous medium, with the other particles and/or the container walls tending to slow their movement flaky or plate-like particles will orient to maximize drag while sedimenting, shining the reported particle size in the smaller direction. A light scattering device will average the various dimensions as the particles now randomly through the light beam, producing a distribution of sizes from the smallest to the largest dimensions.