One of the most magical qualities created in representational painting is the illusion of depth on a flat surface. The better we understand the two forms of perspective involved in the illusion, the easier it becomes to represent.
What is Perspective? The word perspective, when applied to art, signifies the accurate depiction of objects from a certain vantage point on a two-dimensional surface so that their relative height, width and position to one another portray depth. The two terms used in artistic perspective are: 1) linear, which relies upon drawing accuracy and 2) aerial, which relies on the effects of atmosphere.
What is Linear Perspective? The idea that objects of similar size appear smaller as the distance between the objects and a viewer increases is referred to as linear perspective. Objects containing parallel lines will have one or more vanishing points in relationship to the perceived eye level, which is associated to the horizon line in nature. Subject matter, including still life, interiors and structures often rely heavily on linear perspective. The more symmetrical the object, such as railroad tracks, the easier it is to see the effect, but every object in a painting features some degree of linear perspective.
What is Aerial Perspective? The effect that atmosphere has upon objects as they recede into the distance is referred to as aerial perspective. The farther away objects become from the viewer, the weaker their contrast appears. Extremes of lightness and darkness, color saturation and detail decrease, and the general color temperature shifts towards a cooler blue tone. This is due in large part to the scattering of light rays in the particulates of water vapor and haze that are contained within the air. John F. Carlson described the phenomenon of aerial perspective in his landmark book, Carlson’s Guide to Landscape Painting, as the compounding of the skylight across the surface of the earth. As things recede, they receive more of the blue skylight. This makes sense when we imagine the sun as a light bulb and the blue ozone sky as the lampshade.
The Perspective of Disappearance: Leonardo da Vinci referred to the effects of perspective upon objects as “The Perspective of Disappearance.” By applying the rules of linear perspective, understanding that no matter where a viewer of a painting is standing in relationship to the painting, he or she will psychologically place his or her eye level to the perceived height of the horizon line at a width relative to the center of the painting. Therefore, all the objects portrayed in the painting need to relate to the surfaces they are positioned upon relative to the distance they are from the observer. When linear perspective is correct, it’s time to portray the atmospheric effects by depicting distant objects as lighter, cooler and grayer. Even when this is not easily perceived, a subtle manipulation of aerial perspective can go a long way in making a painting more lifelike. Ultimately, painters are magicians, and perspective is just one of the tricks we can keep up our sleeves.