CHAPTER SEVEN
VALUE
In the world of art and design the term value refers to relative light and dark. Much of our perception is dependent on being able to distinguish light and dark; such contrasts of value are very important in understanding our visual environment. Natural and artificial light sources are the generators of all value. Without a light source we have no contrast; we have darkness. The type and intensity of light source influences the way we perceive value. A light bulb, for example, gives a very different illuminating quality than natural daylight on the same subject.
Value scales depict transitions in value from light to dark. Common increments on the scales are seven or nine steps from white to black, but the steps could be in the hundreds as the real range of value is infinite. An interesting visual phenomenon occurs when a square of the same middle gray is placed in the center of each step of the value scale. All the interior squares are exactly the same gray but the small squares on the light end of the value scale appear considerably darker than those inside squares on the on the dark end which appear much lighter. This phenomenon can be called value interaction. This is an important concept to be aware of as it clearly shows that the perception of all values – and everything has a value – is affected by values around them. In other words values interact. When we look at a gray horse standing in front of a white barn it appears darker than it does standing in front of a gray haystack or a black mound of earth where it will appear a darker gray.
VALUE TO DESCRIBE
As a contour line is used to describe the linear qualities and edges of shapes, value can be used to show how a light source affects a space, shape, or mass. This often involves trying to imitate the shadows cast by and on the objects being depicted. This emulation of shadows and light is called shading or rendering.
Chiaroscuro is an Italian term referring to a systematic approach to shading. It attempts to carefully define how light affects a surface. Many times it tries to use only value to describe and eliminates all use of contour line. Tenebrism is chiaroscuro taken to extremes. The Tenebrists were artists who used exaggerated lights and darks to create dramatic effects in their works. One of the originators of this practice was the Italian artist Caravaggio who in the early 17th Century used stark light and dark contrasts to create theatrical compositions, usually of religious subjects. Caravaggio’s huge paintings seem to be larger than life “stills” from a stage production with spot lit subjects. Later in the 17th century the use of dramatic light was brought to its unsurpassed height by Rembrandt.
VALUE TO EMPHASIZE
There is often a section of a composition that the designer wishes to be an area of emphasis, a place in the work that the viewer’s eyes are guided to. Many techniques can be used to create these focal points or areas of emphasis and a major one is the use of value. An obvious way to use value contrast to focus the viewer on an area is to have a generally dark use of value throughout the composition and have the focal point be very light. The strong contrast of the isolated light area in a field of dark immediately draws us to the light area. The reverse of this process works well also, when the designer keeps light values dominant and uses heavy dark areas as emphasis points. There are many steps between these two polarities in which more subtle use of value can create emphasized areas of varying intensity. Most compositions have values working to create emphasized areas but the average viewer is not conscious of them. Students of design can learn much by analyzing the lights and darks in masterworks, studying how the eye is led through the composition.
VALUE TO EXPRESS
Value has expressive and emotional overtones. Dark values can be thought of as gloomy, ominous, dramatic, or even frightening. Light values are generally considered to be more cheerful, positive and uplifting. Grays have a multitude of expressive qualities with middle grays usually thought of as neutral, boring or subdued. These generalized expressive qualities can and often are used by designers to create moods and expressive qualities in their works. It must also be considered that not everyone has “generalized” reactions to value. Each individual has a backlog of reactions to light and dark that might not fit neatly with research. Each person brings to a work of art his or her own unique associations.
Art history abounds with individuals who were masters of expressive value: Goya, Picasso, Klee, Kline, and in our own time Anselm Kiefer . For the ultimate example of expressive value my own preference returns us to Rembrandt. Certainly his value was used to describe his figurative subject matter, but the true genius of the work was in the power of value to express emotional qualities. In some of his works this expressive quality (created by value and other elements) is truly beyond words. The emotional qualities of some of his paintings can only be experienced personally and then fully only in the presence of the original. Reproductions cannot convey the complete impact of the work.
VALUE AND THE BIG PICTURE
The term value as used in design can at first confuse the beginning art student, who has used the term and heard it used to refer to worth, price or degree of excellence. Value also finds its way into the fine art world of music. There it has the meaning of the relative duration of a musical note. There is also the mathematical use of the term value as a numerical quantity assigned or computed.
Another application of the plural term “values” can apply to ideals, morals, ethics, beliefs and customs. This use of the term returns us to our design definition of contrast between light and dark. In the subjective area of “values” there is also a scale of good and bad, right and wrong, that could be equated with values of light and dark.
Design, economics, music, mathematics, and morals all claim the term value. It is a very complex word and one that must cause some confusion in those people learning English as a second language.
PROJECT #8: VALUE SCALES AND CHIAROSCURO
materials: Illustration board 14″ X 20,” pencils 2H-HB-2B, eraser, ruler, black marker.
objective: to produce two controlled value scales and then apply the skills and control learned in the scales to the rendering of a geometric still life.
procedure:
1. put a 1″ border on the illustration board.
2. 1” down from the top border with ruler draw a nine step value scale: each square 1 1/2″ square, 1/2″ between, start first square 1/4″ from left hand border.
3. inside each of the 1 1/2″ squares (except #5) draw a 1/2″ square.
4. using the HB pencil smoothly render #5 square a medium gray; then shade all the 1/2″ squares in the other eight 1 1/2″ squares the same medium gray as in #5 (use no finger or stump blending in any of this project).
6. next shade #7 to be a value half way between #5 and #9; then shade #3 to be a value half way between #1 and #5. Finish with values #2, #4, #6, and #8. ( Use the pencils best suited for the value…2H will produce lighter values as it is a harder graphite, 2B will produce darker values as it is a softer graphite, HB is between the two.)
7. 1″ below the nine-step scale draw a continuous bar 1 1/2″ wide the same length as the upper scales.
8. shade this bar as a blended run from white to black. It should follow the same value transitions as the nine-step scale but with no breaks; each value should smoothly blend into the next.
9. from the clearly illuminated set of plaster geometric forms set up in the room render a cube and sphere on the lower section of the illustration board. Use the careful process of chiaroscuro, attempting to capture all the subtle variations of light on the surface of the objects and all the shadows that they cast on the tabletop. Use some exaggerations of light and dark to enhance your illusion of volume. Use little or no line.
10. on the front, lower border label with your name and Value Scales and Chiaroscuro.
Kommentarer