A 35mm WW2 Japanese Type 89 “Rokuoh-Sha” (made by Konica) Air force Machine Gun Movie Camera that they used for Training Machine Gunners. This could be mounted on the wing and controlled remotely (by the wires in the case) or mounted in the Waist Gunner’s position for hands on target practice.
See that yellow plastic like dome ? That would hold a stop watch which would be activated when the Trigger was pulled and because of a prism mounted near the end , the face of the watch would also be shown in the “Movie” it was shooting. This way a Gunner could be shown how long his bursts were and taught how to better handle the weapon.
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