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

Series — page 3

A field says what an essay is about. A series follows one idea essay by essay — from the question that introduces it to the one that assumes all the others.
3 m, 50 mm1.50 m, 25 mmsubject ×1.000000 · background ×0.526 · zoom alone would give ×1 for bothnear-to-far ratio 10.00 → 19.00changing the focal length leaves it at 1.000000000000

Dollyzoom

  1. 1 Stepping closer is not zooming
  2. 2 A dolly zoom is a step and a zoom, and they meet at one depth
  3. 3 A dolly zoom off the axis keeps a line, not a plane
3 essays · sensor points, joinedlines, metevery incidence survives, worst 9.1e-1630 of 30

Duality

  1. 1 A point and a line are one object
  2. 3 Four lines have a cross-ratio
  3. 4 The horizon has a pole
3 essays · foundations 1234512345a point is chosen hereand must be on this linematch to its own epipolar line: 1.4e-13 px5 of 44 correspondences drawn

Epipolar

  1. 1 A point is a line over there
  2. 2 The two pencils keep one number
  3. 3 Rectification is a family, not an operation
3 essays · twoviews epipoleepipoleleft pictureright pictureepipole from 44 correspondences vs the projected eye: 1.1e-9 px2.60 m between the eyes

Epipole

  1. 1 The image of the other eye
  2. 2 An epipole in the picture leaves a blind disc
  3. 3 A sway gives the blind centre a depth, not a good one
3 essays · twoviews 3 m · 47 px6 m · 24 px12 m · 12 pxnear ÷ far = 4.000 against a depth ratio of 4.000exposure 33.3 ms · 6 m/s across the frameeach streak is straight; the set of them is not one kernel

Exposure

  1. 1 A frame is an interval
  2. 2 Turning and travelling blur different worlds
  3. 3 A camera on a bend is sharp on a circle
3 essays · sensor horizon3 vanishing points at a finite distance2564 px · 8129 px · 531 px

Eyelevel

  1. 2 The horizon is at eye level — if the picture plane is vertical
  2. 3 The horizon, and the fraction
  3. 4 A picture with nothing straight in it
3 essays · construction full frame · 39.6°APS-C · 26.6°Micro Four Thirds · 19.6°1 inch · 15.0°phone (1/1.7″) · 8.7°one 50 mm lens · the angle is a property of the rectangle behind itMicro Four Thirds: 2.00× diagonal, 2.08× wide, 1.85× tall50 mm across five formats39.6° down to 8.7°

Format

  1. 1 A focal length is not an angle
  2. 2 Focusing is a zoom
  3. 3 A close picture carries its own distance
3 essays · sensor parallel, 52° above the ground56% · 56% · 56%one eye, 14.5 m away49% · 56% · 49%a square metre of floor varies 1.000× against 1.535×spread across rooms: 0 against 6.2 points

Fukinuki

  1. 1 What the removed roof buys
  2. 2 Measuring a room off the page
  3. 3 What a removed wall costs that a removed roof does not
3 essays · conventions drawn: q = 1, drift +3% a baysteady hand fitted: q = 0.361q = 1 with no driftclosed form q = 0.361rows apart ≤ 0.014 pxsplay 1.32, 6 bays, near edge at the bottomdrift 0.03 → q 0.36

Habit

  1. 1 A tiring hand draws a different habit
  2. 2 A tiring panel keeps its order, not its direction
  3. 3 A strip keeps its ratio, not the end it began
3 essays · choices x/z, y/z — the pinholeM·p, then divide by wworst disagreement 4.0e-14 px over 8 verticescorrect from 21 cm, at 160 mm wide42° across · near 0.1 m, far 1000 m

Homogeneous

  1. 1 The divide is postponed, not avoided
  2. 2 A point at infinity is an ordinary vertex
  3. 3 A texture reaches the horizon as a rate
3 essays · pipeline nothing on the ramp images above its vanishing linehorizonuphilllevelcorrect from 10 cm, at 160 mm wideslope recovered 22.0000° against 22° built

Inclined

  1. 3 The ramp has its own horizon
  2. 4 The line every nosing is on
  3. 5 A measuring point for a ramp
3 essays · construction 15° of yaw, 6° of pitch, 1.50 throw ratio81.3% of the panel reaches the corrected rectangleouter: the thrown quadrilateral · inner: what correction can keep18.7% of the panel discarded

Keystone

  1. 1 A projector is a camera run backwards
  2. 2 A projector in the viewer's eye
  3. 4 Straightening does not move the eye
3 essays · screen no single viewpoint — the rays miss by no distance at all — the rays are parallel13 of 21 faces

Noeye

  1. 1 A picture with no eye
  2. 2 Nothing moves along the direction
  3. 3 One face, one scale
3 essays · parallel 00.50011.50010203040correspondenceepipolar error at every OTHER point, after one match is movedmedian 0.54 pxthe moved oneevery point wrong: median 0.54 px, worst 1.7 pxclean fit 2.3e-13 px

Outlier

  1. 1 A wrong match is not a small error
  2. 2 A mismatch on its own line needs a third eye
  3. 3 A third eye that lands on the next post
3 essays · depth source, 35 cmthe occluder's edgefraction of the source visiblepenumbra 17.5 cmprojection: 17.50 cmsampled: 17.41 cm

Penumbra

  1. 3 The penumbra is the lamp's image
  2. 4 A soft shadow on a curved floor is not the lamp's image
  3. 5 The lamp's size over its distance, and nothing else
3 essays · light -0.400-0.200000.2000.4000.6000.8001position across the drawn surfacehow far along the real surface, minus how far along the drawn one(√k−1)/(√k+1) = 0.5195at the page's midpoint, 40.9%depth ratio 10 : 1peak 0.5195 at s = 0.760

Perspcorrect

  1. 1 A texture does not interpolate on the page
  2. 2 Along a line of constant depth the page is affine
  3. 3 A tilted span walks a staircase
3 essays · pipeline the pivottangent circle, 30.0 mmno single viewpoint — the rays miss by 24.98 mm6 frames · pivot 60 mm off

Pivot

  1. 2 The pivot that is not the eye
  2. 3 The parallax you cannot shoot away
  3. 4 The camera that is a cylinder
3 essays · curved tt′0.003.101.00-2.004.000.502.700.28predicted, not fittedthree pairs givencross-ratio 0.839506

Pline

  1. 2 A line is a space of its own
  2. 3 The map a row of posts is
  3. 4 A line is a closed curve
3 essays · foundations horizon3 vanishing points at a finite distance2564 px · 8129 px · 531 px

Pointcount

  1. 2 One, two and three point are one construction
  2. 3 The arrangement the count cannot see
  3. 5 The third point put where it looks right
3 essays · construction correct from 8 cm, at 160 mm widestretch 1.358 · centres 4.28 px

Quadric

  1. 3 The ball at the edge of the frame
  2. 4 Every quadric has one outline
  3. 5 A curved surface made of straight lines
3 essays · foundations

All essays