Visual Plane
every picture states the point it is correct from
Concept

Edge stretch — where it appears

2 essays name this object, across one field. What follows is each of them, and the objects they name alongside it.
54 px69 px84° across27% wider at the edge

Wide angle is not distortion

A wide lens stretches shapes at the edge of the frame by exactly 1/cos θ — 3% at 28° across, 41% at 90°. Every bit of that is what a correct rectilinear projection must do, and every bit of it disappears if the picture is viewed from the point it was made for. Nobody views it from there.

viewing · widefield flat picture plane — straight lines stay straightcylindrical picture surface — even stretch, bowed linesone scene, two picture surfacesneither is the distorted one

When the picture surface is not flat

A flat picture plane keeps straight lines straight and stretches the edges without bound. A cylindrical one spreads the stretch evenly and bends every straight line that is not through the axis. Neither is the distorted one — they are answers to different questions, and the choice decides what a wide view can be.

viewing · surface

Named alongside it

The objects these essays reach for when they reach for this one.

AnamorphosisBarrel distortionCylindrical projectionEquirectangularfield of viewFisheyeHorizonPanoramaPicture planePicture surfaceRectilinear projectionVanishing point

All concepts