Experimental setup for the speckle interferometer. The letters in the schematic refer to driver with stinger (Dr), violin (V), acquisition system (AS), wave generator (WG), power amplifier (PA), computer (PC), Lumix camera (c₁), webcam (c₂), divergent lens (L), mirror (m), non-polarizing Beam Splitter (NPBS), pinhole aperture (AP), horizontal polarizer (P), laser (LAS), table ([0.5ex]0.15cm1.5pt[0.5ex]0.15cm1.5pt), digital wire ([0.5ex].25cm1.9pt), laser beam ([0.5ex].25cm1pt), angle between the beams (θ), cartesian reference frame (⋅​​ ⋅ ​​⋅). Suppl2.mp4 has a record of this setup working at the end of the video.