The purpose of this article is to question the semiotic functioning of stereoscopic 3D cinema, in terms of the disparity between modes of production and heterogeneous forms of perception and cognition. Based on an empirical study on educational 3D film reception, held in Santiago, Chile, the text identifies three interrelated issues that reflect the conflicting interaction between a visual culture marked by narrative and perspective conventions (2D) and a logic of perception more into space and constructivism (3D).