Brown–Conrady — where it appears
Named by 2 essays across 2 fields — each of them below, with the objects they name alongside it.
Straight lines that are not
Everybody says the edges of a wide-angle frame bow. Nothing is special about the edge. A radial map moves every point along its own radius, so the only line it leaves straight is one through the principal point, and the bend of every other is decided by how far it passes from that one place.
The render is distorted on purpose
A headset renders a bent picture so its lens can straighten it, which is the lens field's polynomial run backwards and the one place on this site where distortion is introduced deliberately. The round trip closes to a thousandth of a millionth of a pixel, and the price is that one rendered pixel becomes 0.646 delivered pixels at the edge of the field and one at the centre.
Named alongside it
The objects these essays reach for when they reach for this one.
Barrel distortionRadial distortionAnisotropyCamera calibrationDemonstrationfield of viewFocal lengthinstrument limitInverse projectionPincushion distortionPrincipal pointResidual