One of the many pleasures to be found in the Garnier Opera in Paris is the library, which contains scores, choreography, no doubt catalogues of costumes and, as seen here, drawers containing models of sets that can be installed in a series of model theatres, so that the sequence of scenes in a performance can be laid out, either in advance of making the sets or with sets that already exist. Some of the model sets also reveal the multiple distortions of perspective to give the illusion of greater depth than there is on the stage while at the same time not making the actors appear to grow as they move towards the rear of the stage. You might need to make the images below smaller to resolve the stereo image.
As with the dioramas, the stereoscopic photography reveals the difference between the material and pictorial space in the illusory construction.
For advice on resolving the images, go back two or three posts.