Equiluminance.

The brilliant gold stars in Van Gogh's Starry Night fade into the background when the painting is seen in black and white. The yellow of the stars' center is equiluminant to the white/beige glow they create in the colored picture. The range of different blues used in the sky and the various white, blue, and gray colors used in the swirling parts of the sky are equiluminant, too, and become one shade of gray when the color is taken away. The hills, which have layers of blue and gray in the original picture, take on a consistent gray color as well in the black and white version of Starry Night.

Van Gogh painted the outlines of forms in his painting with black, so the objects can be seen clearly in both versions of the picture. However, the various beautiful colors that give the objects their rich texture fade into each other in black and white, as if Van Gogh had filled in all of the outlines with single colors.

Interplay of the Subjective and the Objective

For this week’s reading I arbitrarily decided to read the section out of Livingstone’s Biology of Seeing before I read the section out of Solso’s Psychology of Art and the Evolution of the Conscious Brain. This random decision proved to work out well for me, because the information I received from Livingstone’s book was left somewhat jumbled in my understanding. Although Solso covers many of the same topics in the chapter “Art and Vision” (Chapter 3) as Livingstone covers in the 4^th, 5^th, and 6^th chapters of her book, the method of organization of this information Solso uses seemed to be easier understood by me. Particularly, I appreciated Solso’s constant reiteration of the fundamental concepts amongst somewhat science-thick sections.

 

“…our understanding of it is based on a stream of neural activity initiated by light reflected from a surface combined with our existing knowledge. We are AWARE of the content because physical changes take place in our brain and eye.” (Solso, page 76)

“In these routing paths, there is massive interconnection with other regions; in general, the cerebral action takes information from a painting and analyzes it into components while at the same time engaging higher-order processing areas of the brain that makes us aware of the significance of the piece.” (Solso, page 132)

 

These two quotes eloquently summarize key concepts that are detailed in their respective sections. The first quote, from early on chapter 3, delineates the concept of “seeing” as a mode of perception biologically based and experientially based. These two bases are interrelated (as noted throughout the section). This notion gracefully leads into the notion of objectivity vs. subjectivity in perception. Although Solso does not focus directly on this topic, I found it to be one of the common themes throughout the section. I inferred from this reading that Solso’s stance on the struggle between the objective and subjective is analogous to the concept that “seeing is a mode of perception biologically based and experientially based”. Objectivity and subjectivity in perception are two premises that are interrelated and interdependent on one another.

         The second quote I referred to is from the conclusion of chapter 4. This quote synopsizes the pathway of visual information throughout the brain. These pathways are explained in greater scientific detail throughout the chapter, but the idea of “engaging higher-order processing areas” (which is a concept also detailed in the Livingstone reading) didn’t fully make sense until I read this sentence. It seems that (like in the aforementioned quotation) the idea of “interconnection” plays a heavy role in the explanation of perception. This is interesting to me, because if I were to draw something that is interconnected, it may look something like a neuron, or roots on a tree. My artistic interpretation would mimic my neuronal structure, which (as described in our readings) plays an important part in the way I would create / interact with art. This example in and of itself depicts a relationship that is interrelated.

Andrew Wyeth's "Christina's World"

"Christina's World," painted by Andrew Wyeth in 1948 depicts a young girl named Christina who was paralyzed from the waist down due to muscular complications . By converting it into grayscale, the painting lost some of its poignancy. The muted, hushed colors that Wyeth used in the original work complimented the forlorn subject matter and added to the overall impact.

http://www.stefangeens.com/christinas_worldwebsmall.jpg

http://www.wid.info/test/christinas_worldwebsmall.jpg?50025113

I was playing around with luminance settings on paint shop and formed the image on the left with equiluminant colors. The image on the right is what Mr. I would see.

MONET, Rouen Cathedral: Harmony in Blue and Gold (1894)

Claude Monet's "Rouen Cathedral" painting shows his use of integrating colors and by using a fixed color palate, he could create different scales of dark and light in each color. At the time, people regarded his paintings as formless (which can some what be depicted in the gray scale) however with the stublety of shades, Monet created forms and shapes.

This is Claude Monet's Customs House at Varengeville (which is at the brooklyn museum, right around the corner from my house). Here the many subtleties of color are lost as the pigments are taken away. Both in the sky and the sea, the colors run together and become a largely flat grey.

J.M.W. Turner's "Slave Ship" as Equiluminant

In Turner's painting the Slave Ship we see a violent seascape with a vessel in the background and the bodies of the dead and dying that have been thrown overboard in the foreground. The fiery sky accents the tumult of the scene but when reduced to gray scale the image becomes almost unintelligible. As in Monet's Impression: Sunrise the sun in the Slave Ship almost disappears from the sky as does the figure of the ship and the bodies in the water.

Equiluminesant Colors in Van Gogh and Mondrian

There is use of equiluminesant color in each of these paintings.  In the Mondrian compositions the blue and red squares appear to be the same under grey scale and in Van Gogh's "Night Cafe," the greens and purples appear to be the same.

equiluminant colors in art image

The painting is by Mark Rothko called "White Center."  As you can see, the orange and pink appear the same in a black and white grayscale.

untitled by Bridget Riley

When viewed on the gray scale the red, blue and violet shapes appear as one.

Equiliminant Paintings

So I was trying to find a picture that was equiluminant, and I started by reading the website http://www.webexhibits.org/colorart/monet2.html which says that Monet's "Poppies, Near Argenteuil" has equiluminescence. So I started a google image search for a picture that I could post.

In doing that, I discovered that although the painting is SUPPOSED to be equiliminant, many of the online reproductions are not, as evidenced by this grayscale version that the poppies are still clearly distinguishable in. The color version of it even looks different than another color version that IS equiliminant.

Color of non-equiliminant version:


Equiluminant picture:



Equiluminant picture in grayscale:




Finally, here's another poppy picture that is equiluminant:


Its color version:

Perception vs. Reality

How appropriate that I was assigned to elaborate on the readings this week! I feel this way because the Robert Solso chapters elaborated on the neural mechanics of our vision. As my introduction to the class was, “My name is Kristen Gull, and I don’t think I use the left side of my brain,” I thought it was rather appropriate for me to correct myself.

As Solso shows us in Figure 3.11, both sides of our brains are actively involved in processing vision. Some optic nerve fibers cross over into the other hemisphere of the brain, where some others do not. Previously, I had no real clear conception of the wiring of my brain in relation to vision, and I was referring to the fact that I do not do much math or science here at Sarah Lawrence. However, as this class goes to show you, when I do, it’s interesting, art-related science, like this!

Although our vision is made possible by an extremely complex system, we humans tend to look through our eyes without really “seeing” all the time. How many times do you recognize your own ability to perceive colors or depth? I hardly notice my range of visual abilities, except when they are spent towards determining the location and identity of a friend walking by me-- only then do I tend to doubt my ability to recognize faces.

Despite my terrible farsightedness, I do seem to take my vision for granted. I think we all must to a certain extent. In fact, we rely on our vision so much that it is arguably the most important sense that we have. Humans often take this information as inarguable truth. For some, seeing is believing. Why not? We have an amazingly intricate system that helped our ancestors survive for millions of years.

However, sometimes we tend to forget that illusions exist. Not that colors are illusions, but I tend to think that colors are external qualities of an object instead of my perception. As in this Georgia O’ Keefe painting, the colors can be seen by some as consisting mostly of reds, purples, greens, and yellows. When put in grayscale, this painting can be a little confusing. This could appear as a painting of something totally other than a flower, especially if they were colorblind. The reds and the purples are of the same intensity, and if someone was red-green colorblind, I would imagine they would have trouble seeing the purple as well, especially with the green trim around it.

I have so much more appreciation for my vision, despite it’s blurriness without the help of contacts or glasses. It is strange to think that the eyes I see through are the result of the eyes of my ancestors. I certainly am grateful that they developed these wonderful perception abilities. It is strange to think how different my life would be if I saw it through a different lens.

Processing Color

Livingston's colorful optical illusion demonstrations have been incredibly fascinating to me. For certain kinds of illusions, once a person knows the secret behind the trick, the illusion loses its power to fool the perceptions and the “magic” is lost. But with the illusions in Livingston's book, I find that no matter how much I know about the way my brain and my eyes are processing the information to create the illusion, I am unable to NOT see the illusion. For instance, the black and white grid on page 57 continues to shimmer with moving black dots and the red and green spiral on page 67 appears to bounce and pulsate whenever I try to look it over. I actually find both of these illusions quite difficult to look at for long periods of time without becoming somewhat dizzy. Even in reading the adjacent pages, particularly with the equiluminant red and green design, I found it difficult to focus on the words on the page, and instead found myself distracted by the dancing designs in my peripheral vision. I did notice, however, that in dimmer light, the image seems less inclined to dizzy me, and I wondered if it had to do with the overall luminosity of the page.

From our readings, I have become more conscious of color constancy in different lightings. I went to visit my mom this weekend, and the light in her bathroom had been changed from a soft, tungsten bulb to a harsher compact fluorescent bulb. In comparing the new light to the soft light in the hallway (still an older tungsten bulb), I realized that I would use the terms “cool, blue light” to describe the fluorescent bulb, while the terms “softer, redder light” would fit better for the tungsten bulb. I wonder what the spectral signatures of the two bulbs would appear like. It took me a while to adjust to the new light bulb in the bathroom. The colors still look the same, despite the drastically different kind of light. The contrast, though, between the hallway light and the bathroom light is impressive and distracting. I don't think I've previously given the lighting in a room enough credit for the tone and mood it sets.

I was very interested in the discussion of the Mona Lisa painting. One of the reasons why I think the smile is more apparent in the peripheral vision than in the central, more detail-oriented vision is that most of her smile's appearance is due to the facial shadows on her cheeks. These shadows are quite visible in peripheral vision, and they create the sensation of a smile. When looking straight on the mouth, the shadows fade back on her face, revealing her actual mouth formation. In examining the image components on page 73, it becomes clear that the shadows are not perceived at all in the central vision, lending support to my theory. I wonder how well we would be able to interpret the expressions on faces viewed only as blurry shadows.

Livingston says “that high-level cognitive processes, such as language, can override low-level processes, like interpreting emotional states” (73). Further proof of this comes from an experiment one of my psychology classes tried two years ago. We did the Stroop Task, which basically involves attempting to read the color of the word instead of reading the actual words. Part of why this is difficult is that our brains (once literate) are so trained to look for and read the letters/words, that it takes effort to overcome the (now) instinct to read the word rather than the color of it.

Monet's Rue Montorgeuil in Paris, Festival of June 30, 1878 (Livingston, p. 75), illustrates a moving picture. Because of the blurry, undefined edges, the painting appears in life-like motion. Poussin's painting, The Rape of the Sabine Women (Livingston, p. 76), which reproduces a scene in exacting detail, on the other hand, appears still and more like a snap-shot than a moving piece of art. This difference reminds me of a technique I learned for photography. In order to take a picture of an object in motion and make the picture look like it's in motion, either the object or the background must be blurry. Usually, people prefer the background to be blurry, since the object is the point of focus for the photograph. If instead, the photographer uses a faster shutter speed and keeps the camera stationary, the image appears stationary, and the feel of motion is lost. It is only through this blurry quality that a still image can give the appearance of motion and action.

In Livingston's explanations of the “where” and “what” systems of visual processing, she relies heavily on evolutionary biological explanations for the development of these systems. Solso also directs our attention to the evolutionary process that resulted in the development of our current eyes (and that they were not intended to look upon art, but for survival needs) (Solso, p. 84-86). I am curious though, how we know that only the primates have developed the “what” system. What sorts of tests can be/have been employed with animals?

On Seeing Color and Value

The chapters in both The Psychology of Art and the Evolution of the Conscious Brain and Vision and Art: The Biology of Seeing brought me back to experiences I had in my color theory painting course. Looking back through these experiences I am now able to grasp the biology of the “seeing” eye and the “seeing” mind. In the first still life painting I did for that course I differentiated the objects by color. I believe I viewed this still life primarily through color constancy. When I painted a maroon cloth in the still life I used value to differentiate one part of the cloth from the other. I used this technique throughout the painting which consisted of several different hues with various values. During critique my professor tore my painting apart. The fact that I was seeing the still life through color constancy was my primary problem. After attempting the still life once more I noticed I could train my eyes to see beyond the color constancy of any specific object. Rather than one color with different values I now saw that in fact the maroon cloth consisted of deep cobalt in one shadowy corner, a dark forest green in another and a bright orange pink where a strip of sun shine fell on it. At times the cloth did have value distinctions but in many places on my canvas entirely different colors were used to represent it.

What I believe I trained myself to do in that course was to use trichromacy and opponency to a higher degree than constancy. While painting I squinted, used peripheral vision, one eyed vision, and staring to combat the urge to use only constancy when viewing the still life. On page 46 Livingstone writes "Some aspects of visual perception-such as object recognition, face recognition, and of course, color perception-depend heavily on color, and other aspects of vision-such as motion perception, depth perception, figure/ground segregation, and perceiving positional information-are colorblind." Rather than using value to determine depth perception. which is what I instinctively wanted to do, I used my new found in-depth seeing to portray depth with the color that represented that part of that object. In the case of the maroon cloth, bright orange pink accurately represented the spot where the sun shone on it. With a lesser trained eye I saw only a value differentiation not a color difference. On page 51 the Where and What systems further support what I believe I experienced in my art class. The Where system was the part of my seeing that picked out value and wanted to represent the maroon cloth through value only. The What system is the part of my seeing which I honed in order to “see” the cobalt and bright orange pink in the maroon cloth. The amazing thing is that the subsequent painting I painted which used many different hues and value where necessary had a greater perception of depth than the first one which primarily utilized value.

This leads me to what I learned next in my color theory painting course. Color can evoke intense emotion even when a minuscule amount is used of a certain color in an overall impressionistic painting. Livingstone points out that “low spatial precision may lend vitality to a painting because the visual system completes the picture differently with each glance” and Solso makes a similar inference when discussing Monet’s Impression: Sunrise when he writes “Monet has captured the impression of this setting and presented a psychological view of motion and color.” I learned that a tiny strip of lemon yellow on the edge of an impressionistic cloud scape suddenly captures the essence of the sky at that moment in time, daybreak. I also learned that shadows, while representing a type of value, were often represented on the canvas by a specific hue. In other words shadows were not always gray but rather had a distinct color depending on illumination.

Lastly, in my art course we experienced another phenomenon, light source. Some of the art students painted primarily in the evening and some painted primarily during the day. The studio during day time got most of its light from the sun; however we always put on the overhead light source. The studio at night used only the overhead light source. Our paintings of the same still life had dramatic differences. Livingstone touches on this on pages 95 – 98. Often a bright pink bowl in a daylight painting looked grayish greenish pink in a nighttime painting. One question I have is if artists can train their visual cells to see items as they appear in a given light source? Our paintings seemed to suggest that this was the case. Sometimes an art student had to work during the day and during the night and this caused the painter to spend long amounts of time remixing colors on their pallet because the still life simply did not retain the same colors in the different lighting situations.