The Minnaert Project

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The Minnaert Project

• A Visual Approach
• By Xijia Chen

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The Book and The Project

• The Book
• M.G.J. Minnaerts Light and Color in the
  Outdoors
• Scientific explanations for multiple lighting
  phenomenon
• The Project
• Purpose To capture examples of the
  above-mentioned effects in order to demonstrate
  and compliment his descriptions
• Reason A picture is worth a thousand words

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Equipment Used Places Traveled

• Digital Camera
• Kodak DC280
• Places Traveled
• Stanford University, Stanford, CA
• Shoreline Park, Mountain View, CA
• Foster City, CA
• Fishermans Wharf, San Francisco, CA

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Reflection by the Clouds

• Characteristics of Clouds p.324, Section 235
• Dazzling white where sun illuminates them
• Gray underneath as they pass overhead
• Opaque white body -- light reflected by numerous
  droplets of water
• Silver lining if sun is covered by cumulus
  cloud
• Often vivid colors during sunrise/sunset

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Shadows

• When you look at your shadow on the ground, you
  will notice that the shadow of your feet is
  clearly defined, whereas that of your head is
  not. The shadow of the bottom part of a tree or
  post is sharp, while that of the higher part part
  becomes increasingly unclear toward the top.
  p. 4
• Stanford University, CA
• Notice near the base of the lamppost, the shadow
  is distinct and mostly consists of the umbra,
  whereas at the bulb, the penumbra is more visible
  and the shadow is much less crisp.

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Shadows (continued)

• Stanford University, CA
• Notice that the spokes at the bottom of the tire
  are slightly visible whereas those at the top are
  not due to the merging of the penumbra and umbra.
  This is another example of the gradation from
  clear to blurry shadows.

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Differences Between an Object and Its Reflection
(Part 1)

• the reflection of a scene in calm water
  resembles the scene itself upside down. Nothing
  could be further from the truthThe reflection of
  a bank sloping towards a river appears
  shortened p. 11
• El Camino Reale, Stanford, CA
• Notice that the distance from the real car and
  brown hill to the curb (marking the horizon)
  seems larger than the distance from those objects
  to the curb in the reflection

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Differences Between an Object and Its Reflection
(Part 1 continued)

• Explanation Although the object and its
  reflection are identical, their positions are
  different, therefore the perspective of the
  viewer w/ respect to each is shifted differently

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Differences Between an Object and Its Reflection
(Part 2)

• Clouds are never as beautiful as when they are
  reflected in a mirror
• P. 13
• The reflection of clouds in the water is clearer
  than the clouds in the sky.
• P. 20
• Shoreline Park, Sunnyvale, CA
• Notice whereas the sky is almost white, the
  clouds in the canal are fairly distinct

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Differences Between an Object and Its Reflection
(Part 2continued)

• Explanation Mostly psychological
• The reflected view always associated as being in
  a plane
• framing of the picture results in uncertainty
  about the position, giving an impression of
  relief
• Protects our eyes from brightness of directly
  looking at the sun
• Polarization of reflection luster attenuated
  and colors saturated

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Freak Reflections

• A row of houses throws a dark shadow on to the
  road, but in the middle of this you often see
  spots of lightit is reflected by the windows of
  the houses on the other side of the road. p.
  15
• Stanford University, CA
• Although all of these surfaces were in shadow,
  they each exhibit one or more bright spots due to
  reflections from opposing windows.

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Reflections in Soap Bubbles

• Try blowing soap bubblesThe side turned toward
  usshows the same upright images as the spherical
  mirror,the inside backinverts the images. p.
  21
• The magnificent shades of color, the changing
  tints p. 21
• Stanford University, CA
• In the left bubble, both the ceiling light,
  bubble wand and their respective inverses can be
  seen. Although the right bubble only shows the
  ceiling light, the striations of the rainbow
  colors can be faintly seen.

13
Window Glass vs. Plate Glass

• The reflections from windows indicate whether
  they are of normal window glass or plate glass
  if the latter, the images are fairly clear, if
  the former, they are so irregular that the
  uneveness of the glass can be seen clearly
  p.22
• Rengstroff House, Foster City, CA
• Shoreline Park
• Notice how the image in the left window is almost
  a mirror reflection, whereas the cars in window
  on the right curve upward and then back down

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Irregular Reflections by a Slightly Rippled
Surface (Part 1 Houses)

• Dominance of Vertical Lines in Reflections
• A chimney or a thin mast is reflected clearly,
  but the strong lines of the roofs have
  disappeared only the vertical lines are found
  back in the reflections. p. 24
• Foster City, CA

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Irregular Reflections by a Slightly Rippled
Surface (Part 1continued)

• Foster City, CA
• Notice that in both pictures, the vertical lines
  of the chimney are strongly apparent whereas the
  horizontal lines are blurry and indistinct

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Irregular Reflections by a Slightly Rippled
Surface (Part 2 -- Streetlights)

• Vertical Columns of Light (Streetlights)
• Observing a streetlight at night gives us the
  elementary phenomenonan upright line, the
  columns are neatly stacked together and magnify
  each other a horizontal line, they lie side by
  side and broaden the line to a hazy surface.
  p. 24
• Fishermans Wharf, San Francisco

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Irregular Reflections by a Slightly Rippled
Surface (Part 2continued)

• Fishermans Wharf, San
  Francisco
• In both pictures, the reflection of the
  streetlamps are stretched in the vertical
  direction. Since the water is slightly rippled,
  each wave reflects a separate image, gently
  adding up to an elongated column that remains
  vertical in the plane of our eyes regardless of
  whether the lamps are actually in the plane of
  the page (previous page -- the lamp on the left)
  or tilted out of the plane of the page (previous
  page -- the row of lamps on the right). This
  verticality is sometimes affected by factors such
  as wind, etc.

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Closed Light Coils

• Remarkable is the appearance of closed coils of
  light seen when the water surges gently, the
  waves have short crests, and the light source is
  high. p. 31
• Shoreline Park, CA
• Explanation If you look at the water at a large
  angle, the light is reflected by two separate
  spots of light on each wavelet. By looking left
  or right, the reflections will appear to get
  closer together until they fuse into the closed
  irregular annulus that you see.

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The Shifting of Reflected Images Toward the
Horizon

• The reflection of the sun in the waves is a
  dazzlingly bright patch, which, as the sun sets,
  is more or less triangular in shape, showing a
  shift towards the horizon. p. 35
• Foster City, CA Shoreline Park, Sunnyvale, CA
• Notice that the photo on the left (taken towards
  sunset at high wind) has a triangular reflection
  whereas the reflection in the photo on the right
  is very obviously a vertical column

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Stained-Glass Windows

• Even the most brightly colored stained-glass
  windows look dull when seen from the outside.
  p. 124
• Stanford University, CA
• Whereas from the outside, the stained-glass looks
  somewhat dull and dark because the light is
  reflected and the light coming from inside is
  faint, from the inside, the colors burst to life
  due.

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Scattering of Light By Clouds

• Certain kinds of cloud obscure the sharp outline
  of the sun until only a round mass of light
  remains that grows fainter towards its
  periphery. p. 283
• San Francisco, CA
• By blocking the suns disk, the cloud has
  obscured the suns light exactly as Minnaerts
  book describes. Even more intriguing are the
  distinct rays or bands of sunlight that
  emerge from the clouds, tracing a clear path
  across the sky.

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Refraction by an Undulating Water Surface

• When a water surface is not perfectly smooth,
  this is revealed by a change in direction of
  broken rays of light and an uneven brightness at
  the bottom. p. 46
• Stanford University, CA
• The brightness of the water is obviously uneven
  in this fountain behind The Memorial Church.
  Clear patches of bright white interspersed with
  darker colors illustrate the broken rays of
  light effect.

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The Colors of Sunset

• The light that we see at sunset in the direction
  of the sun has the blue component removed, so
  that we see a red sun. Plate 35
• San Francisco, CA
• The scene around Alcatraz at sunset is tinted
  pink because of the scattering of blue light due
  to the longer distance light has to travel
  through the atmosphere in order to reach our
  eyes.

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Miscellaneous

• Distant houses only reflect the light of the
  rising or setting sun p. 10
• San Francisco, CA

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Fin