PERSPRCTIVE AND FORESHORTENING

Perspective in Art.

Perspective is an art technique for creating an illusion of three-dimensions (depth and space) on a two-dimensional (flat) surface. Perspective is what makes a painting seem to have form, distance, and look “real.” The same rules of perspective apply to all subjects, whether it’s a landscape, seascape, still life, interior scene, portrait, or figure painting.

Among the many types of perspective drawings, the most common categorizations of artificial perspective we have, namely, one-, two- and three-point perspective. The names of these categories are base on the number of vanishing points in the perspective composition or drawing.

When you stand in front of a tree, a long trailer, its front and closest parts will appear bigger and taller.

One-Point Perspective one vanishing point is typically used for roads, railroad tracks, or buildings viewed so that the front is directly facing the viewer. Any objects that are made up of lines either directly parallel with the viewer’s line of sight or directly perpendicular (the street road) can be represented with one-point perspective.

One-point perspective exists when the painting plate (also known as the picture plane) is parallel to two axes of a rectilinear scene(a scene which is composed entirely of linear elements that intersect only at right angles). If one axis is parallel with the picture plane, then all elements are either parallel to the painting plate (either horizontally or vertically) or perpendicular to it. All elements that are parallel to the painting plate are drawn as parallel lines. All elements that are perpendicular to the painting plate converge at a single point (a vanishing point) on the horizon.

Two-Point Perspective

Walls in two-point perspective. Walls converge towards two vanishing points. All vertical beams are parallel. Two-point perspective can be used to draw the same objects as one-point perspective, rotated: looking at the corner of a house, or looking at two forked roads shrink into the distance, for example. One point represents one set of parallel lines; the other point represents the other. Looking at a house from the corner, one wall would recede towards one vanishing point; the other wall would recede towards the opposite vanishing point.

Two-point perspective has one set of lines parallel to the picture plane and two sets oblique to it. Parallel lines oblique to the picture plane converge to a vanishing point, which means that this setup will require two vanishing points.

Three-Point Perspective is usually used for buildings seen from above (or below). In addition to the two vanishing points from before, one for each wall, there is now one for how those walls recede into the ground. This third vanishing point will be below the ground. Looking up at a tall building is another common example of the third vanishing point. This time the third vanishing point is high in space.

Three-point perspective exists when the perspective is a view of a rectilinear scene where the picture plane is not parallel to any of the scene’s three axes. Each of the three vanishing points corresponds with one of the three axes of the scene One-point, two-point, and three-point perspectives appear to embody different forms of calculated perspective. The methods required to generate these perspectives by hand are different. Mathematically, however, all three are identical: The difference is simply in the relative orientation of the rectilinear scene to the viewer.

Other Varieties of Linear Perspective

One-point, two-point, and three- point perspectives are dependent on the structure of the scene being ^ viewed. These only exist for strict rectilinear scenes. By inserting into a rectilinear scene a set of parallel lines that are not parallel to any of the three axes of the scene, a new distinct vanishing point is created. Therefore, it is possible to have an infinite-point perspective if the scene being viewed is not a rectilinear scene but instead consists of infinite pairs of parallel lines, where each pair is not parallel to any other.

Zero-Point Perspective

Due to the fact that vanishing points exist only when parallel lines are present in the scene, a perspective without any vanishing points (“zero-point” perspective) occurs if the viewer is observing a nonlinear scene. The most common example of a nonlinear scene is a natural scene (landscape e.g.,a mountain range) which frequently does not contain any parallel lines. A perspective without vanishing points can still create a sense of “depth,” see illustration below.

FORESHORTENING

Foreshortening refers to the Visual effect or optical illusion that an object or distance appears shorter than it actually is because it is angled toward the artistic viewer.

Although foreshortening is an important element in Art where visual perspective is being depicted, foreshortening occurs in other types of two- dimensional representations of three-dimensional scenes. Some other types where foreshortening can occur include oblique parallel projection compositions or drawings.

Foreshortening is an effect which also occurs on automobile wing mirrors than they appear.

Perspective and fore shortening – a way of representing an object as seen along its axis, often such that it appears to be approaching or receding from a viewer.

When we look at a long street, the buildings that are next to us appear bigger than those that are far from us. Human figures will look taller than those that are in a far distance. This is because of perspective. It works on the principle which states that: objects that are nearer to us are bigger and clearer and get smaller and nuclear as they move away from us.

Other basic principles which apply in perspective are:

• All receding lines will appear to converge at an eye level at the same vanishing point.
• All lines above the eye level slope downwards to the vanishing point.
• All lines below the eye level slope upwards to the vanishing point.
• The distance between objects seem to reduce by a half if it is the same between the two objects.
• All horizontal lines will converge at a point on the eye level called a vanishing point.

Therefore, to understand the principle of perspective very well, one needs to understand what we mean by: receding lines, horizontal lines, vertical lines, vanishing point, parallel lines, and eye level.

Other methods of constructing perspectives exist, including:

• Freehand sketching (common in art).
• Graphically constructing (once common in architecture) .
• Using a perspective grid.
• Computing a perspective transform (common in 3D computer applications)
• Mimicry using tools such as a proportional divider (sometimes called a variscaler).

Uses of geometrical perspective is a checkerboard surface or floor. It is a simple but striking application of one-point perspective. Many of the properties of perspective drawing are used while drawing a checkerboard. The checkerboard floor is, essentially, just a combination of a series of squares. Once a single square is drawn, it can be widened or subdivided into a checkerboard. Where necessary, lines and points will be referred to by their colours in the diagram.

IMPORTANCES OF PERSPECTIVE AND FORESHORTENING

1. Helps create space and distance for objects in a composition. For example objects closer to the viewer will appear bigger and brighter yet those farthest or distant will appear smaller, less detailed, less contrasts in tone and unclear.
2. Creates simplicity and reduces over-crowding of the fore ground in a composition
3. Guides the eye into the Art work dimension, produces a feeling of three dimension in a composition.