Flea market mystery object

[IanG]

Copy attachment is my bet. See the third photo. The long bolt pointing up along with the two pins would allow solid attachment to the front and of the camera bed. Having done that, it's pretty straight forward to see how it works.

Another thought is perhaps for enlargements with the original projector.

Ian

[C. D. Keth]

Another thought is perhaps for enlargements with the original projector.

Ian

That would certainly work for a crafty photographer. In fact, that one piece of kit would quite neatly round out an outfit to go on the road and make one's living as a one stop shop.