Marcel Jambon, Set design model for Giuseppe Verdi’s Otello, 1895
Marcel Jambon (1848–1908) was a French scenic designer who built maquettes to plan his theatrical sets.
Marcel Jambon, set design for Tristan and Isolde
A wooden frame supported painted backdrops.
Seeing the sets in 3D allowed him to check the viewing angles and the lighting options of a given set design.
Ariane: built model of act V / by Marcel Jambon
Scenic designers often have a variety of skills in drawing, painting, sculpting, and lighting, and they work closely with the other people in the production, including the director, lighting designer, choreographer, and costume designer.
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Wikipedia on Scenic Design