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

Anamorph — the ladder

3 distinct arguments against one idea, from the one that introduces it to the one that assumes the rest.
  1. eye, 74° offgrey: the word before the projectionblack: the same word, projected

    Anamorphosis is only a viewpoint

    A smear on a wall that resolves into a skull when the viewer stands in one particular place off to the side. It is not a trick added to perspective — it is perspective, with the centre of projection put somewhere nobody would naturally stand, and it is the clearest demonstration there is that every picture has such a point.

    rung 3 · viewing
  2. the sheet, 150 × 105 mmthe eye, 52 mm up and 80 mm backgrey: the word standing upright · black: the same word on the paper142 mm from the sheet's middle

    An anamorph at true size, on paper

    An anamorph is the shadow of the intended picture, cast from the reader’s own eye. Every claim on this site is quoted against an assumed display width because the site cannot know how wide its figures really are; this one is not, because it ships a sheet in millimetres and states where to put an eye.

    rung 4 · viewing
  3. 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.

    rung 5 · viewing

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