Relative pose — where it appears
A chain and an adjustment
Composing pairwise poses along a sequence is supposed to drift. Measured over five links it wanders instead — one chain ends closer to the truth than its own worst link — and the real cost of chaining turns out to be something else entirely.
Four cameras fit, and one of them can see
The essential matrix does not determine a camera pair. It determines four, all of which reproject every correspondence exactly, and the thing that picks one is not more algebra — it is the assumption that the photographer could see what was photographed.
Two views give shape and no size
Every pairwise distance ratio in a courtyard recovered from two photographs matches the real one to fourteen digits. The courtyard's actual size is not merely uncertain — it is absent, and a reconstruction three and a half times larger fits the same two pictures exactly as well.
Named alongside it
The objects these essays reach for when they reach for this one.
BaselineCorrespondencereconstruction ambiguitybundle adjustmentCamera matrixcamera trackCheiralityDriftEssential matrixFundamental matrixrandom walkReference length