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S: illuminance haylee franklin

FC: illuminance. | illuminance. | the senior project of haylee franklin

1: illuminance. | The Senior Project of Haylee Franklin University of North Florida Spring 2012

3: "...the Whiteness of the Sun's Light is compounded of all the Colours wherewith the several sorts of Rays whereof that Light consists, when by their several Refrangibilities they are separated from one another, do tinge Paper or any other white Body whereon they fall. For those Colours are unchangeable, and whenever all those Rays with those their Colours are mix'd again, they reproduce the same white Light as before. " Sir Isaac Newton Opticks (1704) | D E D I C A T E D T O T H E O R I G I N A L C O L O R T H E O R I S T

4: a short introduction to | color theory & luminance | What is color? When you look at a pair of shockingly red heels, where is that red actually coming from, the shoes or the light on the shoes? What is red, anyway? How the Brain Sees Color The retina of your eye contains millions of specialized photoreceptor cells known as rods and cones. There are three different types of cones with photo-pigments that sense three different portions of the spectrum. Each cone is tuned to perceive primarily long wavelengths (reds), middle wavelengths (greens), or short wavelengths (blues). Light at any wavelength in the visual spectrum will excite one or more of these cones. Your ability to perceive color depends upon comparisons of the different signals each cone senses, made by the neural circuitry of the retina. After exciting the proper cones, visual signals pass to retinal ganglion cells (which code color information), then to the lateral geniculate nucleus (LGN) in the thalamus, and onwards to the primary visual cortex. The ability to perceive an object as the same color in different situations is known as color constancy. The brain is able to ignore the continual changes in the wavelength composition of light reflected from a surface. You perceive the color of that surface to be the same, even though there are changes in shade. This stability in the perception of color allows the brain to obtain knowledge about the properties of surfaces, despite constant variations in what reaches the eye from those surfaces. So despite tone, luminance, and surface differences, your eye is still able to distinguish a certain hue as green or violet no matter how distorted, pale, or dark it may appear. The objects we view on a daily basis emit light in various mixtures of the long, middle, and short wavelengths. Our minds perceive those wavelength mixtures as color, and this perception creates questions that color theory tries to explain. Historical Color Theory Color theory is a purely human construct. We need ways to define what we mean by color, and how colors can be ordered, related to each other, and adjusted to become new colors. Great historical minds, such as Aristotle and Leonardo da Vinci, lent their powers of deduction toward explaining color, but the first to gain a detailed understanding of the science of color was Isaac Newton. | Using two prisms, Newton observed that white light was composed of all the colors of the rainbow, and that those colors could be identified and ordered. He recognized that the colors comprising white light are "refracted" (bent) by different amounts, and he also understood that there is no "colored" light (the color being in the eye of the beholder). Instead, there is merely a range of energies – proportional frequencies and the inverse wavelengths. Newton first used the word "spectrum" for the array of colors produced by a glass prism. He even assigned seven colors to the spectrum in an analogy to the musical scale, and used them to create the very first color wheel. Newton included purple not as a viable color, but to bridge the gap between red and violet, thus completing the circle. Since his time, the color wheel has evolved into pyramids, cones and spheres of perceptual shades, becoming more and more defined in the process. With the inception of the Internet, colors have been relegated to strictly defined variables in a sea of code, but even with monitor and print calibration the true nature of color still lies within individual perception. | Newton's color circle

5: Mixing Paint vs. Mixing Light When you mix colors using paint, you are using the subtractive color method. The primary colors are red, green, and blue. Mixing these gives you a sludgy, blackish color. If you subtract the primary colors from white, you get cyan, magenta, and yellow. As you mix them, they tend to get darker, eventually ending up as black. When you mix colors using light, you are using the additive color method. If you mix the primary colors red, green, and blue, you get white light. Adding primary | colors together in different ways generates new colors. As more colors are added to the mix, the result becomes lighter, becoming white. Luminance A color can be defined by hue, saturation, and lightness. Luminance, on the other hand, is a measure to describe the perceived brightness of a color. | You can see that blue has the lowest luminance value and yellow, the highest. Yellow is actually just seven percentage steps away from white. Luminance is dependent on both hue and saturation. Reducing the saturation level of any pure hue to 0% results in a 50%-gray and a 50% value in luminance respectively. So for hues with natural luminance above 50%, luminance decreases when the saturation level (color) decreases. For hues with natural luminance below 50%, luminance increases when the saturation level decreases. When a color image is desaturated to monochrome, hues are reduced to differing values of brightness. Colors that look very different when fully saturated, such as red and blue, are surprisingly close in brightness and thus difficult to tell apart in monochrome. | When reduced to pure luminance, an image becomes starkly different from its full-color version. Color is rendered obsolete in view of the form, and values of luminance once shackled to a particular hue are free to be any color that the viewer may imagine.

6: how to use this book. | on the first page, you will be confronted with a black & white image, and a series of tones. | try to guess which tones appear where in the image. | once you have decided where you think the tones appear, turn the page to see the full-color image. | you may be surprised.

7: please, enjoy the illuminance.

89: works cited / image credit | Model: Nisa Farren Color theory introduction paraphrased from http://www.webexhibits.org/causesofcolor/ Douma, Michael, curator. Cause of Color. 2008. Institute for Dynamic Educational Development http://www.workwithcolor.com/ WorkWithColor. 2008. Newton quote, original color wheel: http://www.gutenberg.org/files/33504/33504-h/33504-h.htm Newton, Isaac. Opticks. 1730. London: William Innys, St. Paul's. Project inspired by: http://design-seeds.com/ Design Seeds - for those who love color

91: about the artist | Haylee Franklin is a 25-year-old, Florida-born, fine-art and portrait photographer who learned everything she knows from the fantastic professors at the University of North Florida. The photographs in this book were inspired by work done and techniques learned in Professor Dominick Martorelli's advanced class Fashion As Art.

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Haylee Franklin
  • By: Haylee F.
  • Joined: almost 8 years ago
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About This Mixbook

  • Title: illuminance.
  • The book for my Senior Portfolio class. Last one for university, baby!
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  • Published: over 6 years ago