Visual Perception. Visual contrast

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Transcription:

TEXTURE

Visual Perception Our perception of the visual shape, size, color, and texture of things is affected by the optical environment in which we see them and the relationships we can discern between them and their visual setting. If our visual field were undifferentiated, we would be unable to identify anything. As a perceptible change in tonal value, color, and texture occurred, however, we would begin to discern an object or figure as differentiated from its background. To read the lines, shapes, and forms of objects in our field of vision, therefore, we must first perceive contrast between them and their background. Visual contrast

In representing surface qualities on a twodimensional picture plane, it is necessary to use one or more of the following attributes: Tonal value Pattern Texture Color and so on.

Tonal Value Tone and value are achromatic terms that are defined along a continuum from white to black. These terms are also are used to describe light and dark colors, but refer only to their relative lightness or darkness, not to the intensity of the hue.

Tone is a basic and important attribute of form. Without differences in light and dark, it would be impossible to perceive figures and forms. Tonal value can be used to communicate depth and distance, visual texture and pattern as well as to define edges and shapes of figures and forms. The color, texture, and pattern of surfaces articulate the existence of planes and influence the visual weight of a form.

Tone creates contrast between an object and its background or other figures or forms within the visual field. This contrast between the light and dark communicates which forms are in front of others in the visual field and how far apart the forms are positioned.

When tone is used to define the volumetric shape of a form, dark areas appear to exist farther from the light source and lighter areas appear to exist closer to the light source. The lightest area on the object, called the highlight, is the area closest to the light source

Tone defines shade and shadow on threedimensional forms as well as in two-dimensional compositions.

Texture Texture is the specific quality of a surface that results from its three-dimensional structure. Texture is most often used to describe the relative smoothness or roughness of a surface. It can also be used to describe the characteristic surface qualities of familiar materials, such as the roughness of stone, the grain of wood, and the weave of a fabric. Texture refers to the three-dimensional structure of a surface.

Texture is perceived through either of two senses, Touch Sight. Tactile textures are perceived through the sense of touch. Visual textures are perceived through the sense of sight.

Tactile Textures Through the sense of touch, people can feel surface irregularities and describe the felt textures as rough, smooth, bumpy, wavy, angular or curvilinear. They are often also visual textures, since the light source creates contrast between the different surfaces of a texture, allowing them to be seen and differentiated.

Tactile texture is real and can be felt by touch; visual texture is seen by the eye. All tactile textures provide visual texture as well.

Our senses of sight and touch are closely intertwined. As our eyes read the visual texture of a surface, we often respond to its apparent tactile quality without actually touching it. We base these physical reactions to the textural qualities of surfaces on previous associations with similar materials. Physical texture Visual texture Material texture Texture is intertwined with our senses of sight and touch.

Visual Textures It can be created by the artist, architect or designer on a picture plane through the use of a variety of techniques and media.

Trompe l oeil is a French term that means fool the eye. It is used in reference to a drawing or a painting that represents actual figures and forms and their surfaces and textures so realistically that the viewer belives the work is the real figure or form.

Observing Texture Close Up or at a Distance Textures are an integral part of the environment. Texture is an important characteristic that can help distinguish between different objects within the visual environment.

Representing Texture Through Drawing Many interesting textures can be represented by combining different drawing media and techniques. Representational textures can be created through painting, drawing, rubbing, embossing, folding and piercing. These can be tactile or visual textures simulated to look like real surface textures.

Texture and Scale Scale, viewing distance, and light are important modifying factors in our perception of textures and the surfaces they articulate.

Texture and Scale All materials have some degree of texture, but the finer the scale of a textural pattern is, the smoother it will appear to be. Even coarse textures, when seen from a distance, can appear to be relatively smooth. Only upon closer viewing will the texture s coarseness become evident. The relative scale of a texture can affect the apparent shape and position of a plane in space. Textures with a directional grain can accentuate a plane s length or width. Coarse textures can make a plane appear closer, reduce its scale, and increase its visual weight. In general, textures tend to fill the space in which they exist visually.

Texture and Light Light reveals the shape, color, and texture of objects.

Texture and Light The viewer is able to determine the shape, depth, contour or color of the texture by the way light falls upon the surface. Surface and shape attributes become visually evident because of the differences in light wavelengths and the contrast between highlight and shadow perceived by the viewer.

Texture and Light Light influences our perception of texture and, in turn, is affected by the texture it illuminates. Direct light falling across a surface with physical texture will enhance its visual texture. Diffused lighting deemphasizes physical texture and can even obscure its threedimensional structure. Smooth, shiny surfaces reflect light brilliantly, appear sharply in focus, and attract our attention. Surfaces with a matte or mediumrough texture absorb and diffuse light unevenly and, therefore, appear less bright than similarly colored but smoother surfaces. Very rough surfaces, when illuminated with direct lighting, cast distinct shadow patterns of light and dark. Lighting direction affects our reading of texture.

Texture and Light Diffuse or multiple reflections occur when light is reflected from matte or unpolished surfaces. Angle of incidence equals angle of reflectance. Opaque materials block The transmission of light And cast shadows. Diffused transmission occurs through translucent materials, such as frosted glass. The light source is not clearly visible. Non diffuse transmission occurs through clear, transparent materials, such as glass and some plastics. Specular reflection occurs when light is reflected from a shiny, opaque surface.

Texture and Light Even though these objects may be uniformly illuminated, their surfaces differ in brightness according to their color value and texture and, consequently, their ability to reflect light.

Texture and Contrast influences how strong or subtle a texture will appear to be. A texture seen against a uniformly smooth background will appear more obvious than when placed in juxtaposition with a similar texture. When seen against a coarser background, the texture will appear to be finer and reduced in scale. Finally, texture is a factor in the maintenance of the materials and surfaces of a space. Smooth surfaces show dirt and wear but are relatively easy to clean, while rough surfaces may conceal dirt but may also be more difficult to maintain. Contrast affects the apparent strength or subtlety of adjacent textures.

Texture and Contrast Texture can also result from the manner in which materials are assembled in construction.

Texture and Contrast Contrast in brightness aids our perception of shape and form.

Texture and Pattern Texture and pattern are closely related design elements. Pattern is the decorative design or ornamentation of a surface that is almost always based on the repetition of a motif a distinctive and recurring shape, form, or color in a design. The repetitive nature of a pattern often gives the ornamented surface a textural quality as well. When the elements that create a pattern become so small that they lose their individual identity and blend together, they become more texture than pattern. A pattern reduced in scale becomes texture.

Texture and Pattern A pattern may be integral or applied. An integralpattern results from the intrinsic nature of a material and the way it is processed, fabricated, or assembled. An applied pattern is added to a surface after it is fabricated or built. Integral patterns Applied patterns

Texture and Space Minimal texture Textured Texture is an intrinsic characteristic of the materials we use to define, furnish, and embellish interior space. How we combine and compose differing textures is just as important as the composition of color and light, and should suit the desired character and use of a space. Texture filling space Competing textures

Texture and Space The scale of a textural pattern should be related to the scale of a space and its major surfaces, as well as to the size of secondary elements within the space. Since texture tends to visually fill space, any textures used in a small room should be subtle or used sparingly. In a large room, texture can be used to reduce the scale of the space or to define a more intimate area within it. A room with little textural variation can be bland. Combinations of hard and soft, even and uneven, and shiny and dull textures can be used to create variety and interest. In the selection and distribution of textures, moderation should be exercised and attention paid to their ordering and sequence. Harmony among contrasting textures can be sustained if they share a common trait, such as degree of light reflectance or visual weight.

Texture and Space Increasing textures in a room from left to right