Abstract: A composite projector gate, aperture and light dowser assembly for a cinematograph film projector. The film guide surface through the gate area is curved convex towards the light source, film being held to curved marginal guides by flexible bands anchored before the gate, in the direction of film motion. A quick-release anchor is provided to retain the tension springs. The projection aperture comprises a removable plate in front of which, towards the light source, are spaced-apart heat screens with a horizontally-moving light-dowser blade therebetween in a space in which is provided forced air ventilation.