Final answer:
Value in art refers to the lightness or darkness of an area. A medium value might be represented by a gray-painted wall, while a dark value could be a piece of dark furniture. Observing the pupil during changes in lighting shows how it adjusts in size to manage different light levels.
Step-by-step explanation:
Value in art is defined as the relative lightness or darkness of a shape in relation to another. When describing an area of a room with medium value, one might refer to surfaces or objects that exhibit gray tones that are neither very light nor very dark. An area with dark value, on the other hand, could be characterized by elements with low light reflection, appearing closer to black. For instance, in a room, a medium-valued object could be a gray-painted wall, as it reflects a mid-level of light. A dark-valued object might be a piece of furniture like a dark brown or black bookshelf, absorbing most light and appearing to have little to no reflectance.
Take-Home Experiment: The Pupil provides a practical example of observing changes in value, but within a biological context. When observing someone's pupil in normal room light, its diameter is small due to the adequate lighting. However, when the room is darkened and then suddenly lit again, the pupil dilates, increasing in size, to adjust to the lower levels of light initially and then contracting rapidly as the light level increases.