What is Perspective?

Perspective is the means by which a three-dimensional world is represented on a flat, two-dimensional surface, be it a canvas or a sheet of paper. We can achieve the illusion of depth and distance on a two dimensional surface by observing the world around us and mimicing these observations.

Observations On Depth And Distance

• Parallel lines that are not in the plane of the picture appear converge with each other in the distance. Think of a long straight train track receding into the distance.
• Vertical lines in in the foreground are still vertical lines in the distance. Look at a line fence posts receding into the distance.
• Object clarity and color:
  
  • Nearer objects are clearer and more detailed. Edges, contours and shading are well defined. Colors are vivid.
  • Distant objects are blurrier and less detailed. Colors are greyer and more muted than those in the foreground. In the far distance, the colors become bluish (except in sunsets).
• Object size: Given two objects known to be the same size, the closer object appears larger and the distant object appears smaller.
• Natural size objects: Figures perceived to be of natural size are nearer to the eye.
• Object Spacing: The spacing between nearer objects appears is greater than that between farther objects.
• Object Overlapping: If an object overlaps another object, the object in front is closer.

Perspective: Learn the theory, then practice it

Those who become enamoured of the practice of the art, without having previously applied to the diligent study of the scientific part of it, may be compared to mariners, who put to sea in a ship without rudder or compass, and therefore cannot be certain of arriving at the wished-for port. Practice must always be founded on good theory; to this, perspective is the guide and entrance, without which nothing can be well done.

Source: A Treatise On Painting by Leonardo Da Vinci

Techniques for Depth and Distance

Aerial Perspective

The air we breathe is is made up not only of gases like oxygen, carbon dioxide, and water vapor, it also has suspended particles of water, dust and ash. When we look at things in the distance, we are see them through a thicker layer of atmosphere than we do when we observe them close up. Some of the light from distant objects gets blocked by the atmosphere, and they look blurrier. Also, the longer wavelengths of light (reds) get filtered by the atmosphere, and the shorter wavelengths (blues) selectively reach the eye. As a result, distant objects look bluer and greyer than they would look close up. Near objects have vivid color and well defined detail.

The terms "Aerial Perspective", "Atmospheric Perspective", and "Color Perspective" all mean the same thing.

Size and Space

Two objects of the same size and spacing will appear smaller and more closely spaced when viewed at a distance than when viewed close up.

Linear Perspective

Linear perspective involves making parallel lines that are not in the plane of the picture appear to meet in the distance. The edges of the road or the rails of a train track are not closer together in the distance. They just look that way. As these parallel lines recede, they come together at a point known as a vanishing point.

Eye level and Horizon

Eye level refers to a plane parallel to the ground but at the level of the observers eye. The term horizon often refers to the line in the distance where the earth meets the sky. In linear perspective, it is the same as eye level. The horizon is the horizontal line in the distance where receding horizontal lines meet. Receding parallel lines above eye level slope downward. Receding parallel lines below eye level slope upward. Realistic pictures have only one eye level, and all elements in the picture are relative to this.

One point linear perspective

One point linear perspective has a single vanishing point. This happens when a rectangular object has one face parallel to the plane of the picture.

This is also referred to as "parallel perspective".

Two point linear perspective

Two point linear perspective has two vanishing points. This happens when a rectangular object has no face parallel to the plane of the picture. These vanishing points both land on the horizon.

Three point linear perspective

This happens when a rectangular object has no face parallel to the plane of the picture (like two point perspective), and the object is very tall. Imagine looking up at a skyscraper from below.The sides appear to converge in the sky. Two of the vanishing points are on the horizon. The third is up in the sky.

Overlap

Overlapping is a matter of common sense, and doesn't need much explaining. If an object overlaps another, then it is closer. Conversely, if an object is overlapped, it is further away.

Shading and Shadows

Shading can be used to make an object appear three dimensional, making it more believable. Light shining on an object makes the side nearest to the light source brighter and the side away from the light source darker. The brightness depends both on the angle of the surface to the light source and the distance from it. The light source itself may even be reflected off of the object, looking like an extra bright area (a highlite). Object thickness and shape can be portrayed with altering colors and values, depending on the position of the surface relative to the light source. This is also known as modelling.

Chiaroscuro

Chiaroscuro involves the use of a full range of light and dark values in order to give an object a realistic and solid look. It has bold contrasts between light and dark. Drawings would start out on colored paper and lighter colors would be added on top of this to produce the image. This technique really took hold in the Rennaissance, by artists such as Leonardo da Vinci. The word "Chiaroscuro" is derived from the Italian words chiaro (meaning light) and oscuro (meaning dark).

Sfumato

Sfumato was one of the four canonical painting modes of the Renaissance. Sfumato uses careful, delicate variations of color to define shape. It is like Chiaroscuro but finer. It involves first using a translucent dark paint, and then working an opaque white color into it while it is still wet. The darks will become lighter and the lights will get darker. Through repetition, the result is a low contrast image (smoky in appearance) with very subtle blending effects.

Sfumato is derived from the Italian word sfumare, meaning to evaporate or smoky.

Mona Lisa, by Leonardo Da Vinci is a good example of sfumato.

Grisaille

Grisaille refers to art that has a monochromatic (single color), or nearly monochromatic color scheme. They are usually produced using shades of grey (grisaille), brown (brunaille) or green (verdaille). They may be produced as art for their own sake, be used by engravers, or they may be used as an under painting of an oil painting, where layers of colored glaze are applied over top.

An example of this is the Allegory of Justice by Allegory of Justice by Giotto Di Bondone.

Jan van Eyck Gallery Page 1

Cast Shadows

Shadows cast by objects contribute to the illusion of depth. Shadows happen on the side of the object that is away from the light source. The object blocks the light from reaching that surface, and it is darker. Shadows are darkest and sharpest close to the object and they get lighter and fuzzier the further away you go from the object. They get lighter because of reflected light from the other surfaces and fuzzier because of the diffraction of light around the edges of the object.