"Eisenstein playfully hyped the virtues of the "dynamic square," a screen that was exactly as high as it was wide. He did so in part because to him the square was modern, charged with productive machine force. This more purely cinematic screen was, according to Eisenstein, necessary for properly showcasing the energies, conflicts, and collisions germane to the moving image arts. It would also, at least in theory, be the most accommodating frame, capable of hosting images composed for planes that were either horizontal or vertical. Eisenstein proclaimed that previous industry standards (4:3), as well as contemporaneous calls for wider screens, were nostalgic, calling forth a dated viewing regime dictated by traditional art forms."
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