“…Second, there is complex interplay between displacement error, strain error, and the parameters chosen for the speckle pattern, image correlation and strain calculation [1,3,4,[16][17][18][19][20]. Although several studies have attempted to quantify these relationships, most have been limited to correlation errors arising from rigid body translations [17,21] or no motion at all [4]. Simulated experiments in which displacements are applied numerically to a computer-generated image have also been conducted [3,18,19,22].…”