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Light, Shade, & Value Lecture. Art 120 Drawing 1. Basic Vocabulary. Baseline : the imaginary line on which an object or group of objects sit Converge/Laws of Convergence : come together, meet/orthogonal lines will appear to converge at a vanishing point
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Light, Shade, & Value Lecture Art 120 Drawing 1
Basic Vocabulary • Baseline: the imaginary line on which an object or group of objects sit • Converge/Laws of Convergence: come together, meet/orthogonal lines will appear to converge at a vanishing point • Diagonal Lines: straight lines that are at an angle • Forms VS Shapes in Perspective: square/cube; rectangle/box; circle/sphere; triangle/pyramid; oval/ellipse; cylinder • Foreshortening: a technique for producing the illusion of an object’s extension into space by contracting its form • Horizontal Lines: straight lines that extend to the left & right • Horizon Line/Eye Level: The apparent intersection of the sky and earth/The imaginary horizontal line parallel to the viewer’s eyes
Basic Vocabulary • Orthogonal Lines: Parallel lines that appear to converge at the horizon • Parallel Lines: lines that run together but never intersect • Perpendicular: are lines that intersect at right angles (90o) to each other • Proportion: comparative relationship between parts of a whole and between the parts and the whole • Scale: size and weight relationships between forms • Vanishing Point: the spot on the horizon line (or y-axis for 3pt) that orthogonal lines converge upon • Vertical Lines: straight lines that extend upward or downward
Using Value to Create Depth • General principles • Know your light source or sources’ strength and direction. • Value contrast of objects in space will become closer in value to the background’s value as they recede in space. • Use different value schemes to define different levels of space.
Value • Value is describing relative light and dark in order to capture illusionary volume, mass, space, depth • A simple Value Scale shows figure-ground relationships • Figure-Ground is the condition in which backgrounds tone or hue changes the visual impact of the figure resting on it. The same hue or value appears to be a different depending upon the contrast of tone or hue of the background upon which it is placed. Conversely, two different tones or hues appear to be the same when placed on contrasting grounds.
The Blur Trick • Squint your eyes to blur edges of shapes and tones in space. • Tones will then blend and reveal value patterns and value schemes. • This will allow for quicker layout and assessment of space in terms of value.
Understanding Light through Shadow • There are two types of shadow: Cast and Form • Cast: When an object blocks a light source it casts a shadow. A cast shadow is not a solid shape but varies in tone and value. The farther a cast shadow is from the object which casts it the lighter and softer and less defined becomes its edges. • A form shadow is the less defined dark side on an object not facing the light source. A form shadow has softer less defined edges than a cast shadow. Form shadows are subtle shadows essential for creating the illusion of volume, mass and depth. The changes in form shadows require careful observation – squinting at the subject to see value definition affected by figure-ground making value relationships clearer.
Intuitive Space - Chiaroscuro • Artists of the Renaissance were concerned with showing depth and volume unlike the artists of the Middle or “Dark Ages.” Renaissance artists manufactured the term “Chiaroscuro” to describe how light and dark can imply depth and volume. The word Chiaroscuro is a combination of two Italian words that mean light and dark. (chiaro (clear, light) + oscuro (obscure, dark)
Tenebrism – Dramatic Chiaroscuro • The 17th century introduced a dramatic use of chiaroscuro called tenebrism. Rembrandt perfected this manner of Chiaroscuro. Tenebrism made value an instrument of strong contrast that lends itself to a dramatic and even theatrical style of using light and dark contrast. The tenebrists were interested in peculiar lighting causing mood or emotional expressionism. The deviation from standard light conditions into unexpected lighting locations creates unusual and special effects. • Today, this style is often used by photographers.
Sfumato • Sfumato, (from Italian sfumare, “to tone down” or “to evaporate like smoke”), in painting or drawing, the fine shading that produces soft, imperceptible transitions between colours and tones. It is used most often in connection with the work of Leonardo da Vinci, who made subtle gradations, without lines or borders, from light to dark areas; the technique was used for a highly illusionistic rendering of facial features and for atmospheric effects.
Mona Lisa Leonardo da Vinci c. 1503–1506
The Light Side/The Dark Side • Establishing a definite light side and dark side makes round objects appear round and defines the form of an object accurately. Use this simple trick to make your artwork more true to life, separate light tones avoiding figure-ground confusion.. • Modeling is a contrived method of drawing the light and dark value to capture the mass, volume and depth of objects. Rendering is a term used to describe the actual value and affect of light observed in a form/person, etc. • The lightest spot or streak is where the light strikes the subject in exactly the middle of the light side between the shadow edge and the edge of the object. A highlight can be shinny and crisp on a glass or metallic surface, or fuzzy and muted on a dull or textured surface.
Types of Shadow – Core, Midtones, Reflected Light • “Shadow edge” or “core shadow”. The edge where the light is blocked from the light source is the darkest value on the dark side. The core or darkest value blends into the middle tones from the shadow edge on round subjects. • The variable values blended form the shadow edge on the dark side. Again, the dark middle tones are darker than any values on the light side. The human eye can trick the brain into believing the lightest values on the dark side are the same as the darkest values on the light side. If the artist is confused about lights and darks, the rendering is less understandable. • Reflected light: If the object being painted is sitting on a white table, the light from the table reflects back onto the object and makes the shadow side lighter. If the object of the painting is resting by something black or dark, the middle values will become a dark reflection. The concept also holds true when the object of the painting is sitting on a colored surface
Cast Shadows • When the source of light is blocked by an object it casts a shadow. The length and shape of the cast shadow depends on the placement of the light source. Long shadows are cast from a side light source (as from the sun in late afternoon or early evening), and short cast shadows are cast from over head (as from a noonday sun). The shape a shadow casts depends on the shape of the object casting it and how close the source is to the object.
Cast Shadow Vocabulary • The vocabulary used to describe cast shadows in art come from shadow descriptions in astronomy. The umbra, penumbra and antumbra are the three distinct names given to the description of shadows cast by heavenly bodies. The umbra is the darkest part of a shadow considered the absence of light. The penumbra is a lighter outer shadow where the object is only partially obscuring the light. The antumbra is more obscure. When it is visible it seems to extend out from the penumbra in a lighter and less distinct way.
Light Source, Cast Shadow, and the Axis • The distance of the object from the light source affects the appearance of the light and dark side of the object. The closer the object is to the light source the smaller the light side appears to that of the dark side. In addition the light from the light source may appear more cone shaped than a light source from a distance. • The Axis divides the light side from the dark side and defines the angle of the light….
Light Source and Shadow • The shape of the shadow is also affected by the light source. When the light source is from anything but the sun, like a light bulb, the shadow widens the further it is from the object. The sun, meanwhile, casts a “straight” shadow in that it remains true to the objects shape • More Than One Light SourceA shadow is made for each light source present in a scene. If you are inside a room, for example, and there are two lights on, you will cast a shadow from each light source.
Natural Light – Daylight & Shadow • Cast shadows of irregular shapes and in natural sun light are open for interpretation because of the constant changing sunlight. As you work on location, the sun will continue to advance and change while you are drawing. Note the place you want the sun positioned and keep that constant, to avoid a confusing spread of shadows. The nature of shadow is affected by weather, sunlight, moonlight, or artificial light.
Tips to keep in mind:-The darker the shadow, the brighter the light source.-As the shadow is drawn further from the object, the lighter it becomes.
