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Vision and Art

By Margaret Livingstone
ISBN 0-8109-0406-3 , 270 pages, Publisher: Harry N. Abrams Incorporated

Cover, Blurry Mona Lisa

Reviewed by Owen Ransen

In the introduction to this book the Nobel Prize winner David Hubel says "in the future visual neuro-biology will enhance art in much the same way as the knowledge of bones and muscles has for centuries enhanced the ability of artists to portray the human body". Don't be frightened by the words "visual neuro-biology", this book is accessible to any interested reader (without a degree in medicine or biology!)

This book is about the physics and biology of seeing, and how artists have (sometimes unknowingly) exploited quirks in our visual system to trick us, surprise us or simply get their message across. If you create graphics for the computer screen or for the printed page this book will help you do it better, and give you a deeper insight (!) into the visual system.

The list of chapters gives you an idea of what is covered, and again, don't be alarmed by the technical language in the chapter titles, it is all explained clearly within the well illustrated pages:

  1. Fiat Lux: Let there be light
  2. The Eye and Color Vision
  3. Luminance and Night Vision
  4. The First Stages of Processing Color and Luminance: Where and What
  5. Acuity and Spatial Resolution, Central and Peripheral Vision
  6. The Next Level of Color Processing: Surround Effects
  7. From 3D to 2D: Perpspective
  8. From 3D to 2D: Shading and Chiaroscuro
  9. From 3D to 2D: Stereopsis
  10. Illusions of Motion
  11. Color Mixing and Color Resolution
  12. Television, Movies and Computer Graphics

Each chapter has suprises for even the most knowlegable "graphics worker". Did you know that the resolution of colors on your television is much much less than the resolution of the black and white part of the image? And did you know that, within color part of the television signal, blue is given less space because the eye is less sensitive to blue than to green or red?

There is an explanation of the strange sun in Monet's painting "Impression Sunrise". The pulsating effect is achieved because, though the sun is diffirent in color from the surrounding clouds, it is equal in value (luminance, brightness). Since our eyes are less sensitive to color differences than value differences the sun, in the painting, seems to pulsate. Livingstone attributes this to the fact that we have two parallel vision systems, the color system and the brightness system.

One quote from the book I found fascinating. We think we see images, but in reality we don't. "Vision is information processing, not image transmission". There is no "little man" or "homonculus" inside your head which looks at an image transmitted by the optic nerve to a TV screen stuck to the inside of your skull.

"At every stage in vision, neurons perform calculations so that the end result is information about what is out there in the world, not a picture to be looked at".

I can see this is true, it must be true, but I can't get out of my mind the idea that I am looking at an image of the world!

Livingstone gives an interesting analysis of why the Pointillist paintings give a bright shimmering effect. According to Seurat it was because he mixed light and not paint. According to Livingstone it all has to do with the size of the dots, and how much of a single receptor in the eye each dot covers. And her arguments are born out by an experiment she does (and which you can do too).

Everyone interested in art, graphic design or computer graphics will get something out of this book, which is well worth its US$45 price tag.

Owen F Ransen is the president of Ransen Software, makers of the easy-to-use graphics software packages Repligator and Gliftic. Author contacts





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