 Its high flammability was legendary since it self-explodes when exposed to temperatures over 150° C in front of a hot movie-projector beam.While celluloid film was standard for 35mm theatrical productions until around 1950, motion-picture film for amateur use, such as 16mm and 8mm film, were on acetate "safety base", at least in the US.Celluloid was useful for creating cheaper jewellery, jewellery boxes, hair accessories and many items that would earlier have been manufactured from ivory, horn or other expensive animal products.