In understanding patterns of daylight illumination, it is first important to differentiate between the qualities of sunlight versus daylight. Together, sunlight and daylight create a vast array of illumination patterns. Variations in colors, shadows, and highlights all contribute to our perception of daylight spaces. The more a designer understands about how the physics of daylight and the biology of human perception interact, the greater the potential to turn science into art, and vice versa.

Our perception of color is a great joy, and a function of five contributing factors: the spectrum of the light source; the properties of the material we are looking at; the sensitivity of our retina; cognitive processing; and finally, the cultural context. Shadows and highlights importantly contribute to our understanding of three-dimensional space. Without them, the visual environment looks flat and dull. The distinction between attractive highlights and sparkle versus uncomfortable glare is one of degree. Avoiding glare is often presented as the primary objective of daylit buildings, but we currently lack good methods to really understand and predict it. There is considerable evidence that people prefer looking out windows at views despite predicted glare. It may be time to completely rethink our understanding of visual quality, by putting view quality into the equation.