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

Reflection — where it appears

2 essays name this object, across 2 fields. What follows is each of them, and the objects they name alongside it.
grey: the reflectiontwo routes, agreeing to 0e+0 px after one flip

A mirror is a second camera

Reflect the scene and photograph it, or reflect the camera and photograph the scene. The two routes disagree by 315 px and agree to the last bit once one axis of the image is reversed — which is the whole of why a mirror is said to swap left and right, written down.

light · mirror the sheet, seen from abovemirrorthe eye, 2.4 radii upwhat stands up in the mirrorthe light path reverses to the eye to 1e-15scale varies 7.2× across the design

The cylindrical mirror unbends it

Put a mirrored cylinder in the middle of the sheet and the light path from the eye to the paper bends once. The map that results is not a homography and not a projection in the plane sense at all — it varies its scale by a factor of seven across the design, which is why the smear is unreadable and why the mirror can put it back.

viewing · anamorph

Named alongside it

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

Area scaleAzimuthCatoptricCatoptric anamorphosisChiralityCylindrical mirrorHandednessLight pathMirror planeVanishing pointVirtual image

All concepts