Notes, summaries, assignments, exams, and problems for Visual arts

Tangencies

Making Tangents

Two Circles

• External Tangents: Draw another circle concentric to the larger one with radius R - r. Join the centers. This is the bisector. Draw an auxiliary circle to the centers. Join the center with the points of intersection with the smaller circumference and extend. Where the lines intersect the larger circle will be the tangent points. Parallels are drawn to the smaller circle to find all points of contact.
• Internal Tangents: The process is the same, except that the circle is of radius R + r, and the parallels are drawn to the opposite side.

Tangent to a Circle Passing Through Point P

• If the tangent is to be external, a concentric circle of radius R + r is drawn. From P, an arc of radius R is drawn, which intersects

Audio Visual Q1: Color Theory

Color Description

• Chroma: How pure a hue is in relation to gray.
• Saturation: The degree of purity of a hue.
• Intensity: The lightness or dullness of a hue (adding black or white).
• Value: A measure of the amount of light reflected from a hue.
• Shade: Produced by the addition of black.
• Tint: Produced by the addition of white.

Color Systems

• Subtractive Color: Used when mixing colors with paint. Begins with white and ends with black (CMYK).
• Additive Color: Used on computers. Begins with black and ends with white (RGB).

The Color Wheel

• Primary Colors: The basic essence; these colors cannot be created by mixing others.
• Secondary Colors: Colors achieved by mixing two primary colors.
• Tertiary Colors: Achieved by mixing primary and secondary

The Point

A circle and a line are tangent if they intersect at exactly one point. Two circles are tangent if the line joining their centers is tangent to both. An oval is a closed curve formed by arcs of circles and symmetrical about two perpendicular axes. A ball is a closed curve composed of arcs symmetric about one axis.

Graphical Representation of the Point

Graphically, the point is the minimal footprint of a graphical tool. Geometrically, it is the intersection of two lines. The point can take several forms depending on the instrument used to create it: oval, star, round, polygonal, etc.

Sensory Perception of the Point

• Single Point: Located in the center of a bracket or blade, it creates a sense of order or balance. Located at one end, it creates

Polygon

A polygon is a flat geometric figure bounded by a closed traverse that does not intersect itself.

Classifying Polygons

Polygons are basically classified into:

• Regular Polygons
• Irregular Polygons

Regular Polygons

A regular polygon has all sides of equal length and all its vertices lie on a circle. They are classified as:

• Equilateral Triangle: A regular polygon with 3 sides.
• Square: A 4-sided regular polygon.
• Regular Pentagon: A regular polygon with 5 sides.
• Regular Hexagon: A 6-sided regular polygon.
• Regular Heptagon: A regular 7-sided polygon.
• Regular Octagon: An 8-sided regular polygon, and so on.

Regular Polygon

Irregular Polygons

An irregular polygon has sides that are not of equal length and/or its vertices do not lie on a circle. According to... Continue reading "Understanding Polygons: Types, Properties, and Classifications" »

The Point: Foundation of Visual Form

Defining the Point

The point is the smallest element that can be drawn. Its form is considered indefinite when it is very small, as its shape is conceptually round.

Expressive Capacity of Points

The expressive capacity of the point is demonstrated when a set of points produces an effect of depth or volume. An example of this is concentration, where points grouped closely together can create a sense of density or focus.

Dimensional Capability of Points

The dimensional capability of the point also relates to how a set of points can create an effect of depth or volume. This can be achieved through techniques such as overlap, variations in size, and the use of color.

The Line: A Point in Motion

Understanding the Line

The... Continue reading "Visual Elements: Point, Line, Plane, & Texture in Art" »

Understanding Color: Rainbows, Light, and Pigments

A rainbow occurs when sunlight passes through raindrops, separating the light into seven colored lights.

Absorption conveys the feeling of color when light illuminates an object. The object's surface absorbs some of the light. This property is called the absorption of light.

Reflection is when light is not absorbed but rejected, changing direction and creating the sensation of color.

Color is the name for each color and describes the colors that comprise their mixture (e.g., yellow and green make yellow-green).

Value and Saturation

Value describes the degree of clarity or obscurity of a tone, i.e., the amount of white or black in the composition. For example, magenta can be light, dark, or very dark.... Continue reading "Understanding Color: Rainbows, Light, Pigments, and Saturation" »

Map Projection

A map projection is a system of ordered correspondence between points on the curved surface of the Earth and a flat surface. These points are located on a network of meridians and parallels, in the form of a mesh (creating a series of distortions). Good projections must have two characteristics: to retain the areas (equivalence) and retain angles (conformity). Depending on which point is considered the center of the map, it is distinguished between:

• Polar projection: The center is one of the poles.
• Equatorial projection: The center is the intersection between the Equator and a meridian.
• Oblique or slanted projection: The center is any other point.

Functions of the Projections

Conformal Projections

A map projection is conformal when... Continue reading "Map Projections: Types, Functions, and Uses in GIS with GPS" »

Understanding Space and Visual Perception

Space is the medium in which we move. It is unlimited and three-dimensional, meaning it has three dimensions: height, width, and depth. Through these, we can understand the form, saturation, and position of any solid body.

The way our eyes perceive space, the visual field, is divided into two general planes: the plane of the sky and the plane of the earth. These are separated by the horizon, seen at the eye level of the human observer. Each observer perceives their environment from a single point of view, which changes simply by altering the direction of their gaze or the position from which they observe.

Representing Three-Dimensional Space on a Plane

Drawing on a plane (which has height and width) is... Continue reading "Visualizing Space: Perception, Perspective, and Artistic Techniques" »

Architectural Elements of the Dome

The exterior of the Florence Cathedral highlights its magnificent dome, which features a distinctive pointed ogival profile. The dome is composed of three primary parts:

• The Tambour (or Light Body): This octagonal section features eight panels, formed by slabs of green and white marble.
• The Oculus (or "Egg"): A circular window, serving as a classic architectural element and light source.
• The Cupola Proper: This main section of the dome is formed by eight triangular trusses. The overlying material consists of red brick, surrounded by prominent nerves that discharge weight from the drum. The lantern, crowning the dome, is made of white marble.

Engineering Challenges and Innovations

The construction of the dome presented... Continue reading "Brunelleschi's Dome: Florence Cathedral's Architectural Triumph" »

Sulfate Minerals