Light in painting serves both technical and aesthetic purposes. Technically, it is essential to visual representation, as it conditions the perception of color, texture, and volume. Aesthetically, its interplay with shadow and its effects on color and illumination shape the composition and the image the artist intends to convey. Light may also acquire symbolic meaning, especially in religious contexts, where it is frequently associated with divinity.
Because light produces visual impressions in the human eye, it is indispensable for perceiving art. It is likewise inherent to painting, since the interaction of light and shadow underlies drawing, and its relationship with color is fundamental to modeling and relief.Souriau. 1998 p. 750
The depiction of light has evolved throughout the history of painting, giving rise to techniques such as shading, chiaroscuro, sfumato, or tenebrism. Light has been especially influential in periods and styles including the Renaissance, Baroque, Impressionism, or Fauvism.de la Plaza Escudero y Morales Gómez. 2015 p. 274 The heightened attention to light in painting is known as "luminism", a termterm applied to styles such as Baroque tenebrism and Impressionism, as well as to movements of the late 19th and early 20th centuries, including American, Belgian, and Valencian luminism.de la Plaza Escudero y Morales Gómez. 2015 p. 527
Optics Light (ultimately from Proto-Indo-European *lewktom, with the meaning "brightness") is an electromagnetic radiation with a wavelength between 380 nm and 750 nm, the part of the visible spectrum that is perceived by the human eye, located between infrared and ultraviolet radiation. It consists of massless elementary particles called photons, which move at a speed of 299 792 458 m/s in a vacuum, while in matter it depends on its refractive index . The branch of physics that studies the behavior and characteristics of light is optics.Diccionario Enciclopédico Larousse. 1990 p. 1925
Light is the physical agent that makes objects visible to the human eye. Its origin can be in celestial bodies such as the Sun, the Moon, or the stars, natural phenomena such as lightning, or in materials in combustion, ignition, or incandescence. Throughout history, human beings have devised different procedures to obtain light in spaces lacking it, such as torches, candles, candlesticks, lamps or, more recently, electric lighting. Light enables vision and is itself perceptible as a visual phenomenon. It makes color visible:Navarro. 1999 p. 7 light rays reach the retina, which transmits signals to the brain via the optic nerve.ABC de la pintura. 2002 p. 4 Perception of light is partly psychological, so individuals may perceive the same object or luminosity differently.Arnheim. 2002 p. 311Objects have varying luminance (or reflectance), absorbing or reflecting light to different degrees. This affects perceived color, from white (maximum reflection) to black (maximum absorption), both considered gradations of brightness rather than chromatic colors.Schneider Adams. 2004 p. 61-62 When white light strikes a colored surface, only photons of that color are reflected; if these illuminate another similarly colored surface, they reinforce its saturation—an effect called radiance.Yot. 2011 p. 15 Sunlight contains a continuous spectrum of colors that can be separated into the rainbow hues.Yot. 2011 p. 13 Atmospheric scattering affects their perception: shorter wavelengths (blue) scatter more easily, giving the sky its color, while denser atmospheric conditions at sunset favor the perception of longer wavelengths (red).Yot. 2011 p. 14
Color corresponds to specific wavelengths of light. The chromatic circle represents primary colors (lemon yellow, magenta red, cyan blue), their secondary mixtures (orange red, bluish violet, green), and tertiary combinations. Complementary colors are opposite on the circle, while adjacent colors lie close together. Mixing adjacent colors produces shading; mixing complementary colors creates neutralization. Color is defined by hue (position on the circle), saturation (purity), and value (luminosity), which increases with white and decreases with black or complementary colors.Asunción. 2002 p. 29-31
The Sun is the principal source of natural light, whose appearance varies throughout the day. Mid-morning and mid-afternoon light is generally clear and bluish; midday light is white and intense, with strong contrasts; dusk and sunset light is softer and warmer, ranging from yellow to red.Yot. 2011 p. 27-36 Cloudy conditions produce diffuse light with soft shadows, while night light—lunar or refracted sunlight—is dim and scattered. Indoors, natural light is similarly diffuse and lower in intensity; its contrast and color depend on the number of openings, time of day, and reflective surfaces. North light, entering from north-facing windows, is valued for its constant, soft, and even illumination.Yot. 2011 p. 43
Artificial light includes several main types: fire and candles, which produce red or orange light; electric light—usually tungsten or wolfram—typically yellow or orange and either direct or diffused; fluorescent light, which is greenish; and photographic flash, which is white. Many environments contain mixed lighting, combining natural and artificial sources.Yot. 2011 p. 55-62
Visible reality consists of a balance between light and shadow, with shadows forming when an opaque object blocks light. The gradation between light and shadow depends on the illumination and on objects that may generate additional shadows. Under certain conditions, one element may dominate, as with the brightness of snow or fog or the darkness of night. Lighting dominated by light tones is termed high key, while lighting dominated by dark tones is low keyYot. 2011 p. 16
Shadows may be self shadows (shaded areas on the object itself) or cast shadows (shadows projected onto surrounding surfaces). Self shadows reveal volume and texture; cast shadows define spatial relationships.Yot. 2011 p. 54 Shadow structure includes the penumbra, the darkest area, and the umbra, the lightest. Their appearance depends on the size and distance of the light source: small or distant sources produce sharper shadows with dominant penumbra, while large or close sources create more diffuse edges with stronger umbra. Shadows may also be modified by a secondary or “fill” light. Their color, generally between blue and black, varies with contrast, transparency, and translucency. Natural light produces parallel beams and shadows that respond closely to terrain and obstacles; artificial light produces divergent beams with softer boundaries and may create overlapping shadows when multiple sources are present.Asunción. 2002 p. 40
Light reflection produces four related phenomena: glints, which are direct reflections of the light source; glares, created by illuminated reflective surfaces; color reflections, generated by adjacent colored objects; and image reflections, produced by polished surfaces such as mirrors or water. Light also generates phenomena of transparency and translucency in non-opaque bodies, producing filtered light. This effect can also be created through materials such as curtains, blinds, fabrics, or through trees and other partially permeable surfaces.Asunción. 2002 p. 41-42
Pictorial representation of light
In artistic terminology, light refers to the point or center of luminous diffusion within a painting, or the illuminated areas in relation to the shadows. It also designates the type of illumination used—zenithal (vertical), high (oblique), straight (horizontal), or studio light (artificial). Accidental light denotes non-solar illumination, such as moonlight or artificial sources.Lucie-Smith. 1984 p. 120 Light may enter the composition from various directions: lateral light emphasizes texture; frontal light minimizes shadows and volume; zenithal light, falling from above, slightly distorts forms; upward or contrapicado light exaggerates distortion; and backlight obscures the figure’s silhouette.
According to its distribution, light can be homogeneous (evenly spread), dual (figures emerging from a dark background), or insertive (interplay of light and shadow).Triadó and Subirana. 1994 p. 93 By origin, light may be intrinsic (uniform, without strong effects), characteristic of Romanesque and Gothic art, or extrinsic (with contrasts and directional sources), frequent in the Renaissance and Baroque. Extrinsic light includes focal light, which may be tangible (from a visible light-emitting object) or intangible (from an unseen source); diffuse light, which softens contours; real light, aiming to represent sunlight with precision; and unreal or symbolic light, typical in sacred imagery.Triadó and Subirana. 1994 p. 94-95 Depending on intention, light may be compositional (organizing the scene) or conceptual (enhancing meaning), as in Caravaggio’s selective illumination.Triadó and Subirana. 1994 p. 95 Light may be ambient—without defined shadows—or projected, which produces shadows and aids modeling. The light source is the object emitting light, while the light focus is the most luminous area of the painting. The interplay of light and shadow is chiaroscuro; when darkness predominates, it becomes tenebrism.In painting, light is represented rather than physically present, allowing the artist full control over its origin, intensity, and visual effects.Gualis, Lorente, and Zamora. 2010 p. 229 Light structures the composition, while shadow provides solidity, volume, and expressive potential. The representation of light requires defining its nature (natural or artificial), origin, intensity, and chromatic qualities. Natural light varies with season, time of day, and weather; artificial light varies by source—candles, torches, lamps, neon, and so forth. Light may be focused or diffuse, and its chromatic value affects the tonality of objects, as well as the ambience and projected shadows.Braunstein and Roig. 2010 p. 10-11 Colors appear fully saturated under correct illumination; in shadow, they darken and help define form. Light is inseparable from pictorial space and thus from perspective. In linear perspective, light models volume through gradations of value; in aerial perspective, it reproduces atmospheric effects. The light source may appear within or outside the scene, and may act directly or indirectly. Spatial definition arises from the contrast of light and shadow, with value scales ranging from soft transitions to sharp contrasts.Asunción. 2002 p. 37-38 Spatial boundaries may be objective (objects, architecture, landscape) or subjective (atmosphere, depth, voids). In perception, light creates proximity and darkness distance, so a gradient from light to shadow produces a sense of depth.Asunción. 2002 p. 43Aspects such as contrast, relief, texture, volume, gradients, and the tactile quality of an image depend on light. The interplay of light and shadow defines the position and orientation of objects in space; for accurate representation, the shape, density, and extent of shadows, as well as their variations in intensity, must be considered. Beyond its physical properties, light can also introduce dramatic effects and impart emotional atmosphere.Braunstein and Roig. 2010 p. 5-6 Contrast is a fundamental pictorial resource, shaping the structure of the image. It may be luminous—either chiaroscuro (light and shadow) or surface contrast (a point of strong brightness)—or chromatic, which may be tonal (contrast between tones) or based on saturation (a vivid color against a neutral one). These types of contrast often coincide in a single image.Asunción. 2002 p. 10 Varying the intensity of contrast is a principal artistic tool for determining expressive character, from softness to stark dramatization. Backlighting is one of the most dramatic effects, producing elongated shadows and deeper tonalities.