ARTS 231 - Vocab (Value, Edges, Light & Shadow)

Value

The art element that describes the darkness or lightness of an object. There are an infinite number of possible values in nature because of the intensity of light. On a surface, the number of values is much more limited, both by the darkness of the media used, and because all light off of an object is reflected light, rather than emitted light.

Value Scale or Chart

Is a chart showing different values from light to dark. These can be in any number of steps. Typically 7 or 9 step scales are used, with the middle number being a 50% gray.

High key

A value structure within a composition that keeps all the values in the range between white and a 50% gray. Often used to evoke an ethereal, soothing mood.

Low key

A value structure within a composition that keeps all the values in the range between black and a 50% gray. Tends to evoke a somber, frightening or mysterious mood.

Full range

A value structure that utilizes the entire range of values available to the media being used.

Limited range

A value structure that utilizes a subset of consecutive values available to the media being used. For example, a drawing might keep the value range between 3 and 5 in a 7 step value scale, using any value that falls within the top and bottom of that range. Any range is possible, depending on the desires of the artist, but a limited value range is usually a conscious choice. However, the media might well dictate what appears to be a limited range. For example, a graphite drawing on pale gray paper would look quite limited in value range if matted or framed in black. This would be due to contrast.

Contrast

Anything that shows a difference between pictorial elements. Within the context of value, contrast refers to the relative lightness or darkness of elements. High levels of contrast draw attention and are said to advance, low levels of contrast tend to deemphasize and to recede.

High contrast

A value structure that utilizes large differences between elements in terms of value. A black and white image is the highest possible contrast. High contrast images are powerful graphic statements.

Low contrast

A value structure that utilizes small differences between elements in terms of value. A very restricted limited range drawing would fit in this category. Low contrast images tend to be subtle and often delicate statements.

Conservation of values

A concept in the use of values within paintings, drawings or photographs. The idea is that a limited number of values provides a stronger visual structure to a work of art. Black and white reproductions of old masters works reveal that they rarely used more that 5 or 6 specific values within a single piece (except in the softening of edges). This does not hold true for impressionists work, which is about color and other effects, and translates poorly to black and white.

Chiaroscuro

The use of strong contrast between light and dark, usually bold contrasts affecting a whole composition. It is also a technical term used by artists and art historians for the use of contrasts of light to achieve a sense of volume in modeling three-dimensional objects and figures. The more technical use of the term chiaroscuro is the effect of light modeling in painting,drawing or printmaking where three-dimensional volume is suggested by the value gradation of color and the analytical division of light and shadow shapes—often called shading . The more extreme version with high contrast objects or figures emerging from very dark backgrounds is known as “Tenebrism”. Think Caravaggio.

Edges

Where one value touches another value. Edges can define the physical edges of an object, but will be seen only if there is a value (or in the case of painting or photography, color) between the object and the background or other object behind it. Edges can also define the shift in brightness of light as it hits an object, or the difference between areas in light and in shadow.

Hard edges

A hard edge is an abrupt change in value, regardless of the relative values involved. Hard edges advance in a composition. In other words, they attract attention and function well as focal points. How hard an edge is in a range, relative to the other edges in a composition. Hard edges are often found at the edges of objects, and at the interface of cast shadows and light.

Soft edges

A soft edge is a slow, diffuse change in value, regardless of the relative values involved. Soft edges recede in a composition. In other words, they deemphasize elements and areas within a composition. Soft edges exist in a range, relative to the other edges in a composition. A soft edge can be so subtle as to be imperceptible. They are are often found as light slides off of curved surfaces and falls into shadow, and when objects from a great distance cast a shadow. Nearby artificial lights can also cause soft cast shadows as the shadow gets further from the object casting it.

Sfumato

is a painting technique which involves blending the edge between colors or values so that there is a soft transition. The term "sfumato" is Italian which translates to soft, vague or blurred. For our purposes it refers to an edge so softly blended that it’s boundaries are imperceptible.

Light

Light is what illuminates the world, without which we would see literally nothing. For our purposes here, we can define light as either the effect of light hitting a surface, reflecting off of a surface, or emanating, such as a lit sky or light bulb. Light striking an object can be subdivided into a few categories, but for simplicity let’s explore just two, highlight and halftone.

Highlight

The brightest area of a lit object. Technically, the highlight is the area of the object most directly facing the light source. The highlight location will vary depending on the orientation of the viewer and of the light. As you move, so will the apparent highlight. Highlights are also how we know something of the texture of a surface. Hard surfaces have small, crisp highlights, soft or textured surfaces will show a more diffuse highlight.

Halftones

The areas of an object in the light, but where the light is striking at an angle and therefore not as bright as the highlight. For any given object, the darkest areas of the halftones will remain lighter than the lightest areas in the shadow.

Terminator

The edge where the light stops and the shadow begins as a form turns away from the light.

Shadow

The areas of an object that are not hit by direct light. There are a number of terms used to describe different kinds of shadows, and different elements within the shadow.

Form shadow

The areas of an object that are in shadow due to the direction of the light hitting them. Form shadows are what give an object its sense of shape and surface, and are the characteristic tool used in Chiaroscuro to develop that sense of three dimensional space. On rounded objects, form shadows will be soft at the terminator as the surface gradually turns away from the light.

Core shadow

The darkest areas in a form shadow with the least amount of reflected light lightening them. Generally core shadow will exhibit very soft edges, and makes a great accent.

Cast shadow

A shadow cast by an object (seen or unseen) upon another surface or object. For any given object, the cast shadow is usually the darkest shadow. Cast shadows are often harder at the edges, as the interrupted light strikes the next surface in a shape dictated by the object casting the shadow. A cast shadow falling on an underlying surface is typically darkest right under the object and gets lighter as it moves away and additional light is reflected into the area. Similarly, the edge of the cast shadow will be hardest by the object casting it and get softer as it gets further away. This effect is more pronounced with artificial light sources than with the shadows cast by the sun.

Reflected light

Reflected light IS NOT light. It is instead light bouncing up into a shadow area and lightening the shadow. In many cases it is best to make certain that the reflected light never gets as bright as even the darkest areas in the light. Structurally it is still part of the shadow. You can prove this to yourself by squinting at your subject. You will usually find that the reflected light, however flashy, still lies within the dark side of the big divisions of light and dark.

Squinting

Squinting is an invaluable technique for judging relative values in observational drawing. When outr eyes are open, they constantly adjust to see the greatest range of values in whichever area we are looking at now. If looking at shadows we will see all kinds of lights. When looking at lit areas we will see all kinds of darks. We will be seduced and confused by color and detail. But squinting allows us to see the big value structure of our subject without these distractions. Do it often, especially when first determining the values structure of your subject and when thinking about your composition. Do it again when checking yourself. It’s by far the best way to know for sure whether something is in the light or in the shadow.

Emphasis

Is a principle of design that enhances variety, because it creates a feeling of dominance and subordination. Sometimes in a specific area in a work of art is emphasized.  This emphasized area is called the focal point, and is usually characterized by the use of a higher degree of contrast (in one form or another) than is exhibited in the rest of the design.  This could take the form of hard edges, higher value contrast as well as contrasts of scale, texture, shape, technique or color.

Negative Spaces

Empty spaces surrounding shapes and forms. The shape and size of negative spaces affect the interpretation of positive spaces. 

Positive Space

Shapes or forms in two-and three-dimensional art.  Empty spaces surrounding them are called negative spaces.