Picture space is the surface area upon which a work of art is created. The picture space will assist in deciding the size of shapes and images and where they will be placed. It will also help you to determine how many shapes and images or how many colors to use in any given work of art. For art projects, a limited palette is usually more effective with a small picture space than it is on a larger space. Similarly, a variety of colors and large shapes usually work better on a large picture space than they will on a smaller surface.
Line refers to the direction that the viewer's eye travels when he observes a drawing or painting. Ideally, the colors and forms in the painting will lead the viewer's eye from the lower left corner to the focal point, which is usually placed off center. Artists also tend to place balancing elements near the focal point to sustain the viewer's interest. After this, the eye will normally travel right, so most artists will try to lead the viewer back toward the center of the painting. Otherwise, the eye might travel off the canvas. A well-constructed composition will keep the viewer's eye fluidly moving around the work.
Depth is the illusion of a third dimension. With depth you can make shapes and objects on a flat surface appear to be closer or farther away. An artist will usually make the focal point of a painting larger and closer to the viewer than the surrounding shapes and objects. They may even appear brighter and more clear than they do in real life, while less significant components will be smaller, with less detail. The use of perspective is also important when creating depth in art.
The concept of value in art refers to the amount of light or dark in an area of a painting. For instance, artists often use the illusion of shadow to create dramatic effects. Because light and shadow are opposites, using them together can create the idea of contrast. The notion of good and evil is often conveyed through the use of value.