The Art & Science of Drawing: Week 7: Day 4: The Core Shadow

Day 4 of Week 7 of The Art & Science of Drawing is about the core shadow, the darkest part of the form shadow (the shadow on the form itself). The core shadow appear only on curved forms.

Reflected light

• light that bounces from nearby surfaces on the object and illuminates the form shadow
• important: the line of termination separates the area that is hit with direct light
• the reflected light is less intense than any direct light
• the reflected light is still considered a shadow condition

The Core Shadow

• the shadow area that is not lit by reflected light

Core Shadow Shape

The core shadow is bound by:

• the edge of the object
• the termination line (diffuse)
• the transition to the reflected light (very diffuse)

Core Shadow Value

The core shadow can be changed based on:

• the form of the object
• the intensity of the light
• how much reflected light is received by the object

Core Shadow Edges

• the transition to the reflected light is usually softer than the transition on the line of termination, especially on a sphere (lesson a cylinder)

Demo

Sphere

• draw a circle
• draw the line of termination and fill with a No. 3 wash the shadow area
• draw the cast shadow and shade it
• draw the core shadow
  • use a very soft line to mark the transition from the reflected light to the core shadow - it should be more of a guideline and should not be visible in the final drawing
  • start shading the core shadow area
  • use multiple passes
  • make the transition from the core shadow to the reflected light area very soft

Cylinder resting on its side

• draw the cylinder
• draw the line of termination and fill with a No. 3 wash the shadow area
• draw the cast shadow and shade it
• draw the core shadow
  • the core shadow is a band
  • adjust accordingly the transitions to the lit and the reflected light areas

The Assignment

• light and draw the sphere and the cylinder
• go through the shading steps you learned in the previous two lessons
  • get the basic volumes on the page
  • draw the line of termination and add a No. 3 wash to the shadow area
  • draw and shade the cast shadow
• draw the core shadow as seen in the demonstration