Volume one
The instrument, described the way a camera is described, including what it refuses to do.
It opens with a video game. Mercenaries 2 stores every bone of every model under a 32-bit hash and ships none of the names, and a string that collides with one of those hashes will load the bone perfectly while not being the name at all. The two are indistinguishable by arithmetic. What separated them was a fact from outside the arithmetic entirely: where the bone actually sat.
That is the whole book, applied to light. A glow added because it looks nice is a colliding string: it works and it means nothing. So the aperture is a real pupil, the glass is transcribed from patents, the printing processes absorb light by their own coefficients, and every number in the text is measured against the thing that produced it rather than typed beside it.
It also prints what went wrong. Four aberration terms shipped inverted or scaled, every one of them producing a plausible photograph. That is the argument for measuring rather than looking, made at my own expense.
It will be free to read
The complete PDF, not an extract. A book nobody can read is worth nothing, and the argument is the reason to have made any of this. The hardcover, when it exists, will be a short run, and it will carry nothing the PDF lacks, because a free version deliberately crippled stops doing the only job it has.
Neither is available yet. This page will say so when that changes.