For many years I have been interested in how the mind perceives visual stimuli. After learning the concepts of the subtractive color system and it’s use in process color printing, I was amazed that almost every image we see is comprised of dots called halftones (Hird).
Pass out linen magnifier loop and printed material for class to inspect (30 seconds)
The additive color system is working with light. It is like working with colors on a computer screen. Various combinations of red, green and blue light compose the gamut for adaptive colors. Have you ever notice how an image seems brighter on the screen than when it is printed?
When working with inks or paints an understanding of subtractive colors is necessary because the pigments produce color by absorbing light. The color you see is reflected light. The primary colors of the subtractive system is cyan, magenta and yellow (Hird).
When an image is printed it is separated by CYMK colors, then a screen process is applied to translate tonal qualities. The K stands for black because the although when CYM is overlayed it makes black, that black appears muddy so printers use a true black.
The Halftone process was first developed and patented by William Talbot in 1852. The blending of tonalities happens by alternating dot formations and limiting whitespace (Stalk p.5). Tonal quality depends on the distance of an image from the viewers eye and the lines per inch used.Hold up Ocean print. Ask the back row does this image look continuous? The smaller the dots the more continuous the image appears at close range. Take for instance the printed materials going around the room paper quality also effects the quality of the image.
In modern psychology perception is an active processes that involves the brain to search for corresponding information. Top down process uses our background knowledge to influence our perception of an object. Bottom up begins with the visual stimuli. The stimulus influence our perception. This only occurs when you encounter something for the first time and have no knowledge of what you are looking at. Gestalt Principal attempts to make laws that address how we process images that are not really there. Ah, the treachery of images. Images on TV’s, computer screen, the printed page or even a painting are not what they seem.
I went in to a lot of ad-lib details about each image inspired by this link.
These different approaches can be used against each other in psychological analysis but Csillag (C lag)(2009) believes they can be complementary, if combined into one model for artiest and designers so they gain a better visual understanding. I then started to wonder what’s really going on inside of my body, How do I process what I see?
External visual stimuli enters our eye in the form of light onto our retina. The information is processed in the retina. Retinal ganglion cells carry the visual information to two major visual center of the brain. Ramachndran (2004) would categorize these systems as the old and new visual pathways. The old system take the visual information to the superior colliculus which is located in the brain stem. This visual system deals with locating objects spatially. It enables us to be able to reach for objects and move our eyes towards it (Ramachndran p.28). This visual pathway is similar to the bottom up approach.
Ramachndran conceders the new pathway as the one that goes to the visual cortex. The Information stream is carried to the visual thalamic nucleus which is inside the thalamus, the lateral geniculate nucleus, which in turn sends the informal towards a part of the brain known as the primary visual cortex. The visual cortex is located along the walls of the calcimine fissure (Ashwell p.96). This pathway deals with our ability to recognize objects consciously (Ramachndran p.28). Once an object is recognized we are then able to make the appropriate response to the visual stimuli. This visual pathway is similar to the top down psychological approach. The main thing to keep in mind about the separate neural visual path ways is that they are happing simultaneously.
It is important to differentiate the elements of visual perception that are common to all human from those that are not. Csillag’s model unites psychological analytic approaches, neuroscience and physiological explanations of how the brain relates to art and design principals.
Sensory Impressions : is information receive in the eye. It occurs only in the eye as light, before it becomes a neural signal.
Organizing Process : relates to organization of perception in the primary visual cortex. Can be considered as laws in art. This is similar to the bottom up approach in psychology.
Interpretive Process: Represents the elaboration of the organizing process including the areas of the V2, through V5 of the brain. This is the moment of perception where neural cascades occurs, that vision undergoes our inference of motivation, emotion, personal, culture and other learned symbolic understandings. A Top down psychological approach. But what does all of that mean?
Here is and example of why it’s important to be able to break down the difference process use in looking at an image to aid in image production. The dashed lines represent a geometrical structure in the visual field. The straight lines, arrows and circles indicate the areas of perceptual structure, these are the elements of the composition that is most likely to catch the eye. Those are the areas one would put important visual elements. when composing an image. For visual balance and harmony the area that indicates lightness has fewer visual elements than the area that indicates visual weight, which is where the majority of the visual information should reside. Because we experience gravity the lightness and weight of the two pictorial elements would be categorized in the Organizing Process. All humans experience gravity and this experience is independent from previous knowledge or culture. This figure also contains an Entrance area, Development, and an Action and Energy area. These indicate directional movement in the scene. These three areas can not be generalized to all humans independent of previous knowledge. This directional movement is from right to left therefor, only applies to western cultures. These aspects of the image is an Interpretive Process.
Aesthetics is branch of philosophy that deals with the principles of beauty and artistic taste. Alexander Baumgarten invented the term “aesthetic” as a means to have a “sensate discourse” on poetry (Shiner p.146). It was conceived as a way to discuss the aha sensation within as we perceive an object. In 1790 Immanuel Kant’s Critique of Judgement began focusing on the concept of beauty. He laid down a foundation for aesthetics judgments some of which expressed a universality of beauty even in the absents of concept. Experiences of beauty can be deeply moving, but being moved by art does not necessary mean an object is beautiful. Much of Kollwitz’s work is deeply moving to me but is not what one would consider empathetically beautiful. After attending an Evergreen art series lecture by Thierry de Duve, I became interested in exploring that thing just beyond the knowing, how an art object can become something more than the sum of it’s parts. There are many different philosophical approaches to aesthetics that differ greatly from Kant none are universally accepted.
Neuroscientists such as Ramachardrian and Zeki began to focus their attention on the analysis of artworks in a new interdisciplinary work called neuroaesthetics. Their studies hope to extract rules or laws about art that define beauty and connecting that definition to neural activity. Zeki believes only by understanding the neural laws that dictate human activity in in all spheres,that we can hope to a achieve a proper understanding of the nature of man. (Zeki) There is a danger in universalizing a persons subjective convictions and assume that an art experience of beauty is common to all people (Conway). Two separate people may see and call a color exactly the same but the systematic organization maybe reversed, yet it would be indistinguishable by behavior tests (Slezak p.50). Rakmachandran has a suggested 10 universal laws of art, some of which are covered by Gestalt principals. I find his first law, peak shift very intriguing. Peak shift is about hyperbole in art. How an artist uses pleasurable exaggeration, of the figural primitives forms of our visual perceptual grammar (Ramachndran p.47). Identifying this feature of how our mind responds to some art is an example of Csillag’s Organizing process. The art of caricature is a prime example of this process. The artist exaggerates a persons features more than necessary to make portrait seem more true to life than the subject drawn. Conway urges neuroaesthetic scientists to abandon the pursuit of beauty and focus on uncovering the relevant mechanisms of decision making and reward and the basis for subjective preferences. This search of knowledge returns neuroaesthetics to the original conception of a aesthetics, to be able to communicate what one experiences when ones sees something that is aha inspiring.
Reflecting on Catching the Light, Zajonc quoted Schiller when contemplating the consequences of reductionism of light (Zajonc p. 290). “Schiller believed that art would change society by healing the inner divisions within each individual so that moral and political actions would no longer be a self-imposes duty but a spontaneous expression of the whole person” (Shiner p149). Whether it be art or light the my contemplation of it has broadened my personal horizons. My inquiry of how the mind perceives visual stimuli has taken me to unexpected places, from learning menial job skills of the printing industry to the philosophy of quantum physics. One of the thing I really tried to accomplish with this presentation was tie things i’ve learned in the past to the present. I learned halftone years ago but never thought to ask who invented them and was surprised to learn that Talbot was one of the first to patient an early process. I tried to express my organic process of questioning the world around me into a cohesive whole that shows how interconnected different disciplines can be with the right framing. I’d like to thank you all for accompany me these last two quarters on discovering the entangled properties of inner and outer light.
Trifold Handout
