It is a way of drawing objects or composing scenes to create an illusion of distance. It is the science of vision by which the artist can create the appearance of depth and distance on a two-dimensional surface. It is any graphical system used to create the illusion of three-dimensional images and/or spatial relationships on two-dimensional surfaces.
There are two main types of perspective drawing. These are Linear perspective and Aerial or Atmospheric perspective.
This type of perspective deals with lines and forms of things. It is a method of portraying objects on a flat surface so that the dimensions or sizes of objects shrink or reduces in size with distance. Each set of parallel, straight edges of any object, whether a building or a table, will follow lines that eventually converge at a vanishing point. Typically this point of convergence will be along the horizon, as buildings are built level with the flat surface. When multiple structures are aligned with each other, such as buildings along a street, the horizontal tops and bottoms of the structures will all typically converge at a vanishing point.
There are three forms of linear perspective. These are Parallel / one-point perspective, Angular/ two-point perspective and Oblique/Isometric/three-point perspective.
In parallel perspective, the plane lies parallel to the picture plane and all parallel lines moving horizontally away from the viewer converge at a vanishing point. However, all vertical lines remain vertical while the sizes of the objects reduce in size as they move towards the vanishing point. It has only one vanishing point.
In this type of perspective, the plane is drawn at an angle to the picture plane. It usually has two sets of parallel lines which do not meet at the same point, but rather converge at different vanishing points though they share one horizon. The sizes of objects reduce as they move towards each of the vanishing points. It has two vanishing points.
This type of perspective is characterized by a plane with three equal axes at right angles. It has three vanishing points and as usual, the objects reduce in size as they move towards each of the three vanishing points.
Aerial / Atmospheric Or Colour Perspective
This is the creation of depth or distance in a drawing by the use of colour. Depth or distance is portrayed by reducing the contrast or value in colours of objects in more distant objects, and by making their colours less saturated. This will reproduce the effect of atmospheric haze, and cause the eye to focus primarily on objects drawn in the foreground. Colours of objects closer to the viewer or in the foreground is brighter while colours of objects far from the viewer and above the horizon become pale or dull in value.
The basic principles on which all perspective drawings are based are:
1. Objects in distance appear smaller than objects closer to the viewer.
2. Colours in distance appear duller and paler than objects close to the viewer.
3. Objects close to the viewer always appear sharper and clearer.
4. Parallel lines going in one direction away from the viewer must be seen as converging to the single point on the horizon known as a vanishing point.
5. Parallel lines never meet but that they appear to do so.
The relevant tips for perspective drawings are:
1. The horizon is always at the eye level, no matter how long or high one gets.
2. If an object is above eye level, its underside will be seen.
3. High objects are seen above eye level.
4. Neither top nor bottom is seen if the object is at eye level. Big objects are often seen at eye level.
5. An object is below the eye level if the top is seen. Small and low objects are seen below the eye level.
6. All circular objects are seen in perspective form an ellipse.
Perspective has much relevance in drawing. Some of these have been stated below.
1. It helps in creating the illusion of distance.
2. It helps to add the appearance of a third dimension to a working surface.
3. It ensures simulating on a flat, two-dimensional surface, or in a shallow space the three-dimensional characteristics of volumetric forms and deep space.
4. Aerial or atmospheric perspective is used to blur outlines, limit details, and alters hues toward the cool colours and to reduce colour saturation and value contrast.
5. It helps in grading tones and colours which suggest distance.
Artists must strive to show perspective in their drawings to achieve movement in their works of art.