Real armillary spheres are dense with scales and signs. Ours is polished blank — deliberately, and for composition as much as honesty.
Why the rings stay smooth. An engraved instrument invites reading, and a portrait is not a document. Our armillary sphere is a sculpture of rings: brass, polished, unmarked. It signals study and curiosity without pretending to measure anything, which keeps the frame in the studio and out of the observatory.
There is a practical reason too. Rendered text and fake engraving are the fastest way to ruin an otherwise beautiful generation. A brief that demands smooth, unmarked metal gives the model nothing to misspell — the rings either shine or they do not.
Briefing polished metal. Say what the metal is and what it lacks: ‘smooth polished brass rings, no engravings, no numbers, no markings’. Negative space in a brief is not wasted words; for instruments, clocks and dials it is the difference between a portrait and a diagram.
Place the sphere to one side, never centre. It is a punctuation mark in the composition — the eye should arrive at it after the sitter, the way a reader reaches the footnote after the sentence.