Abstract: A motion picture projector substantially free of picture jump comprises a gate assembly having a projection aperture and a light source for projecting light through the aperture and focusing lens and onto a screen. The film is intermittently advanced through the gate assembly by an intermittent sprocket which is intermittently rotated by a modified Geneva mechanism. The Geneva mechanism comprises a star wheel having a plurality of radially extending slots separated by curved surfaces. A rotating cam has a ring which slidably engages the curved surface of the star wheel and a pin which engages the slots as the cam rotates, rotating the star wheel a fraction of a rotation for each full rotation of the cam. The cam has a tension area adjacent the pin and a relief area remote from the pin. The tension area engages the curved surfaces of the star wheel closely, preventing backward rotation.