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Notes:

We can only see something if the light hits a form and bounces back to our eyes. When light hits a form, it creates a consistent pattern of light and shadow, which we call the five properties of light. By identifying and recreating this pattern, we can draw the look of three-dimensional objects on a two-dimensional surface.

No light means no sight. So, if we turn on the lights, light will hit the surface of a form and gradually fall away. This illuminated area is called the halftone. Within this area, one portion of the form directly reflects light to our eyes, creating the brightest spot, the highlight.

when light hits a form, it creates a consistent pattern of light and shadow we call the five properties of light we can identify and recreate this pattern to draw the look of three-dimensional objects on two-dimensional surface.

as light hits a form, it begins to fade away across the surface, creating a range of values. The area where light gradually falls off is called the halftone. In this area, the brightest spot—where light directly reflects to our eyes—is known as the highlight.

Light also bounces off surfaces. Some of this reflected light returns to the form, though with less intensity, creating what we call reflected light. Imagine throwing a super bouncy ball into a room: each surface it hits absorbs a bit of energy, just as reflected light is softer than the initial light hitting the form.

The darkest part of a form, where minimal light reaches, is the core shadow, often found between the halftone and the reflected light. Additionally, when a form blocks light, it creates a shadow on surrounding surfaces—this is called a cast shadow.

To summarize, the five properties of light are: highlight, halftone, core shadow, reflected light, and cast shadow. Without these elements, your drawings may lack depth and realism.

Shadows also have three specific properties. First, a cast shadow is darkest closest to the object and lightens as it extends away. Second, its edges are sharper near the object and soften with distance. Lastly, a core shadow on the object itself will generally be softer than the harder-edged cast shadow.

If we observe these shadow details, our drawings will appear even more realistic.

Next, let’s apply these concepts to basic forms. Your brain already recognizes these lighting patterns in the real world, like knowing where to pour coffee into a cup or which surfaces are hard or soft. We just need to become aware of what we already see.

• Spheres: With curved surfaces, spheres have gradual plane changes, creating soft, seamless transitions between light properties.
• Cubes: With flat planes and abrupt edges, cubes have subtle transitions on flat surfaces and hard transitions at plane edges. Highlights and core shadows often appear near these edges.
• Cylinders: Cylinders, like spheres, have soft transitions but form straight bands of value, with halftone on either side of the highlight as light wraps around.
• Cones: Like cylinders, cones have bands of light and shadow but narrow toward the cone’s tip.

We’ve been looking at examples with a single, direct light source, which clearly reveals all five properties of light. However, multiple light sources create overlapping light and shadow areas, as in ambient lighting. Although ambient light softens shadow transitions, it may reduce clarity, making it less ideal for showcasing form.