Cal. Penal Code § 17720

The provisions listed in Section 16590 do not apply to any instrument or device, other than a short-barreled rifle or a short-barreled shotgun, which is possessed or used during the course of a motion picture, television, or video production or entertainment event by an authorized participant therein in the course of making that production or event or by an authorized employee or agent of the entity producing that production or event.