singular values — where it appears
Seven numbers no picture can name
Shift a whole reconstruction by a metre and a half, turn it half a radian, scale it by 2.7, and every photograph of it stays where it was to a hundredth of a billionth of a pixel. Move one point by fifty millimetres and they move by two thirds of a pixel.
Eight points and the basis they are read in
The linear system that recovers a fundamental matrix is written in whatever coordinates the marks were read in, and pixel coordinates are a bad choice. Centring and scaling them first is worth nothing at a quarter-pixel reading and a factor of thirty at four.
Named alongside it
The objects these essays reach for when they reach for this one.
Baselinebundle adjustmentConditioningCorrespondencedesign matrixeight-point algorithmFundamental matrixgauge freedomJacobianNormalisationreconstruction ambiguitySimilarity