Final answer:
The lightness or darkness of a surface in art is referred to as 'value', which is pivotal in creating the perception of light and form in two-dimensional artworks, and is measured on a scale from white to black.
Step-by-step explanation:
The lightness or darkness of a surface in art is referred to as 'value'. This element is crucial in creating the illusion of light and form in two-dimensional works of art. It provides a visual cue to the viewer about the depth and structure of the objects depicted. Value is observed on a scale from pure white to black, with various shades of grey in between, representing the range of lightness to darkness. High-keyed values are closer to white, and low-keyed values are closer to black.
Artists employ value to convey volume, depth, and dimension, establishing a figure-ground relationship on the canvas. It's a fundamental component in the principles of composition, helping to organize the artwork visually and emotionally. Edward Steichen's photograph of Brancusi's studio is an example where value plays a significant role in defining the shapes and forms within the work.
Understanding and utilizing the element of value is essential for artists to effectively portray their subjects, influence the viewer's focus, and express the intended mood or narrative through their creations.