Concept
Epipolar geometry — where it appears
2 essays name this object, across one field. What follows is each of them, and the objects they name alongside it.
The image of the other eye
Two photographs of one courtyard, and in each of them a point that is the other camera. It is computed from forty-four matched marks and nothing else, and it lands on the projection of the other eye to about a billionth of a pixel.
A point is a line over there
Knowing where a mark sits in one photograph does not say where it sits in the other. It says which line it is on, which removes one of the two unknowns and leaves one — and the five lines drawn here meet at a point to within a thirtieth of a billionth of a pixel.
Named alongside it
The objects these essays reach for when they reach for this one.
CorrespondenceEpipoleFundamental matrixBaselineCamera matrixdegrees of freedomEpipolar lineFocal lengthResidual