Understanding how light and shadow play across an object will help you describe its form or even make up shadows when you need them. Click on the first image to start a step by step slideshow.
We will use this set of objects to explore the play of light and shadow. For this demonstration, the light will come from the back and left of the drawing.
Core shadow: this is the darkest part of the shadow. It falls on the side of an object away from the light but does not reach all the way to the edge.
Reflected light: place a mid value on the shadow side between the core shadow and the edge. This zone is illuminated by light that reflects off the surface to the right and bounces back into the shadow area. You will not see reflected light if there is no surface to bounce the light back into the shadow or if the surface is non reflective.
Center light and halftone: fade from the dark shadow into the sunlit surfaces. The brightest areas that face the light are called the center light. This light area always faces the light. The halftone is the gradual transition from the core shadow to the light.
Highlight: if the illuminated surface is shiny, it will reflect a bright highlight. This is not the same as the center light. The location of the highlight depends on the angle of the light and the location of the viewer’s eye. The closer you move your viewing angle toward the direction from which the light originates, the closer the highlight will be to the middle of the center light. The more you move your viewing angle toward the shadow side, the closer the highlight will be to the core shadow.
Cast shadow: Objects block light and the cast shadow extends from the side that is away from the light source. Cast shadows will be darker where they tuck up under the object that is casting the shadow. Cast shadows also change their shape as they fall across other objects. Note how the shadow is angles across the angled bar, curved across the round bar, and straight on the ground to the right.
Learning the names of the parts of a shadow will help you remember and identify them when you see them.
